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The West Texas (Permian) Super Basin is the prototype super basin. The basin has produced 28.9 billion bbl of oil and 203 TCF of gas (63 billion BOE, 1920–2019). The US Geological Survey and Bureau of Economic Geology estimate this super basin has remaining reserves of 120–137 billion BOE, twice the volume produced during the first 100 yr of hydrocarbon production. During the past decade, the West Texas Super Basin has been the driver of production growth in the United States and has decades of remaining economic production and reserve growth. The West Texas Super Basin is a complex Paleozoic basin built on a varied Proterozoic crust. After Cambrian rifting, regional subsidence began in the Middle Ordovician and continued into the Devonian, forming the Tobosa Basin. The early Paleozoic Tobosa Basin subsidence terminated during Mississippian epeirogenic uplift. A later stage of subsidence began in the Late Mississippian accompanied by large-scale faulting and moderate folding. This tectonic and structural development was controlled by basement terrains, earlier tectonic, and structure reactivated by compression of the Ancestral Rocky Mountains and Marathon-Ouachita orogenic events. These formed the Permian Basin. The Marathon-Ouachita tectonic event ended in the Wolfcampian (early Permian). Subsidence continued to the end of the Permian (Ochoan). Periodic subsidence during the Mesozoic was likely caused by Rocky Mountain (Laramide) deformation. Cenozoic (late Paleogene–Neogene) western uplift tilted the basin to the east. Each of these events has a significant influence on the basin petroleum systems. The basin has multiple source rocks and petroleum systems formed during various stages of basin development. During the formation of the early Paleozoic Tobosa Basin, Simpson Group and Woodford Shale source rocks were deposited. During the transitional basin development phase, the Barnett Shale source rocks were deposited, and during Permian Basin subsidence, the Wolfcamp and middle Permian (Leonardian and Guadalupian) source rocks were deposited. Continued subsidence into the Mesozoic resulted in the deposition of additional strata. These Mesozoic intervals are now mostly eroded but provided sufficient burial depths for thermal development and increased the extent of thermal effect for maturation and migration of hydrocarbons within these Paleozoic petroleum systems. Leonardian and Guadalupian conventional reservoirs have produced 71% of the resources from all conventional West Texas Super Basin reservoirs. These reservoirs are typically most abundant on the shelf crest (shelf to edge), where reservoir development is maximized and becomes a focus of hydrocarbon migration from the deeper Delaware and Midland Basins source rocks and shallower, more-proximal shelf and platform source rock systems. Unconventional resource reservoir oil production in the West Texas Super Basin accounted for just under 90% of total basin daily production at the close of the last decade (2010–2019). Total West Texas Super Basin production peaked in March 2020 at 4.7 million BOPD. Since that time, production has declined because of lower rates of investment driven by lower product prices. The West Texas Super Basin economic oil and gas production has benefited from an extensive infrastructure, a large geologic and engineering community, regulatory and public support, open access, sufficient capital availability, and a scalable service industry. The paradigm toward new drilling, completion, and production technology has been driven by unconventional resource reservoir development in the basin. These West Texas Super Basin technological developments have lead industry technology for unconventional resource development worldwide. Maintaining talented human resources and capital are challenges that time will tell if individual firms and the industry will meet to develop the hydrocarbon resources within the basin.

Huanggang Dabieshan Global Geopark (DBGG), which is situated in central China, is notable for watershed of geology, climate, geomorphology, hydrology, and species between North China and South China. Scientific value of orogenic belt landscapes in the Dabieshan territory was globally recognized when the Dabieshan geopark gradually promoted under effective management framework of Dabieshan National Geopark was approved by UNESCO Global Geopark Network in 2018. DBGG has abundant geodiversity, showcasing a high representativeness and rarity of the orogenic belt landscapes, in matter of ultrahigh metamorphism, magmatism, bioecology, and culture. In order to assess and evaluate the potential of geoheritages, a detailed field investigation and description has been carried out in several localities of orogenic belt landforms within the DBGG, including Neoarchean gneiss, primitive epeirogenic granites, grotesquely shaped rocks, sedimentary rocks, gorge and floral landforms. And then both qualitative and quantitative approaches are launched to elaborate the values (scientific, educational, aesthetic, recreational, cultural, etc.), levels of significance, as well as their strengths, weaknesses, opportunities, and threats (SWOT analysis). The outcomes show that orogenic belt landforms obtain high assessment values, especially in Tiantangzhai, Bodaofeng, Guifengshan, and Longtan gorge localities. The educational utility (Ved, Vsa) and convenience and attraction for geotourism (Vtr, Vti) achieve high evaluation ratings. The distinct standings of geosites owe to easy accessibility and positive promotion by the community. Finally, valuable experiences have been summarized on the promotion of sustainable local economic development. This useful information could be given to global geoparks which are in its initial stage of development, in terms of preserving geoheritage, developing geotourism, and rural tourism.

Geologic evidence across orogenic plateau margins enables the discrimination of the relative contributions of orogenic, epeirogenic and/or climatic processes that lead to growth and maintenance of those plateaus and their margins. Here, we discuss the mode of formation of the southern margin of the Central Anatolian Plateau (SCAP) and evaluate its time of formation using fieldwork in the onshore and seismic reflection data in the offshore. In the onshore, uplifted Miocene rocks in a dip-slope topography show monocline flexure over >100 km, km-scale asymmetric folds verging south, and outcrop-scale syn-sedimentary reverse faults. On the Turkish shelf, vertical faults transect the basal latest Messinian of a ~10 km fold where on-structure syntectonic wedges and synsedimentary unconformities indicate pre-Pliocene uplift and erosion, followed by Pliocene and younger deformation. Collectively, Miocene rocks delineate a flexural monocline at plateau margin scale that is expressed along our on-offshore sections as a kink-band fold with a steep flank ~20–25 km long. In these reconstructed sections, we estimate a relative vertical displacement of ~3.8 km at rates of ~0.5 mm/y, and horizontal shortening values 5 Ma, and to contextualize the plateau margin as the forearc high of the Cyprus subduction system.

The uplift of the southern African Plateau with its average elevations of ~1000 m is often attributed to mantle processes, but there are conflicting theories for the timing and drivers of topographic development. Evidence for most proposed plateau development histories is derived from continental erosion histories, marine stratigraphic architecture, or landscape morphology. Here we use a landscape evolution model to integrate a large dataset of low-temperature thermochronometry, sediment flux rates to surrounding marine basins, and current topography for southern Africa. We explore three main hypotheses for surface uplift: 1) southern Africa was already elevated by the Early Cretaceous before Gondwana breakup, 2) uplift and continental tilting occurred during the mid-Cretaceous, or 3) uplift occurred during the mid to late Cenozoic. We test which of these three intervals of plateau development are plausible by using an inversion method to constrain the range in erosional and uplift model parameters that can best reproduce the observed data. Results indicate four regions of parameter space that fall into two families of uplift histories are most compatible with the data. Both uplift families have limited initial topography with some topographic uplift and continental tilting starting at ~90-100 Ma. In one acceptable scenario, nearly all of the topography, >1300 m, is created at this time with little Cenozoic uplift. In the other acceptable scenario, ~400-800 m of uplift occurs in the mid- Cretaceous with another ~500-1000 m of uplift in the mid-Cenozoic. The two model scenarios have different geodynamic implications, which we compare to geodynamic models.

A range of geological evidence documents the growth of African topography as a result of sub-plate support throughout Cenozoic times. Recent studies used inverse modeling of drainage networks governed by the linear stream power law to quantify the spatio-temporal history of uplift and erosion across the continent. Here, we test predictions of this uplift rate history by applying it as tectonic forcing to naturalistic landscape evolution simulations. These simulations parameterise dynamic drainage reorganisation, track sedimentary flux, and permit variable erodibility, none of which are feasible in inverse models. Modelled topography, river profiles, drainage planforms and sedimentary flux patterns broadly match observations. We test the sensitivity of forward model prediction to variations in erodilibity by employing spatio-temporally variable precipitation rate. Forward model predictions are relatively robust to even large excursions, suggesting landscapes contain internal feedbacks which modulate these effects and permit close recovery of the geomorphic record of uplift. Wavelet power spectral analysis reveals observed African river profiles are self-similar at wavelengths >~ 100 km, meaning longest-wavelength features have the highest amplitudes. At shorter wavelengths, spectral slopes increase, implying sharper features are generated only at wavelengths

Figures, tables, methods, and datasets.

Plateaus, located far away from the plate boundaries, play an important role in understanding the deep-rooted geological processes responsible for the epeirogenic uplift and dynamics of the plate interior. The Karnataka plateau located in the Dharwar craton, southern India, is a classic example for the plateau uplift. It is explored using orthogonal deep crustal seismic reflection studies, and a mechanism for the epeirogenic uplift is suggested. A pseudo three-dimensional crustal structure derived from these studies suggests a regionally extensive 10 km thick magmatic underplating in the region. It is further constrained from active-source refraction and passive-source seismological data. We interpret the Marion and Reunion mantle plume activities during 88 Ma and 65 Ma on the western part of Dharwar craton are responsible for the magmatic underplating, which caused epeirogenic uplift. Flexural isostasy related to the onshore denudational unloading and offshore sediment loading is also responsible for the persisting uplift in the region. Plate boundary forces are found to be contributing to the plateau uplift. The present study provides a relationship between the mantle plumes, rifting, development of continental margins, plateau uplift, and denudational isostasy. Combination of exogenic and endogenic processes are responsible for the plateau uplift in the region.

©2018. American Geophysical Union. All Rights Reserved. Western North America has an average elevation that is ∼2 km higher than cratonic North America. This difference coincides with a westward decrease in average lithospheric thickness from ∼240 to 260 basaltic samples. Forward and inverse modeling of carefully selected major, trace, and rare earth elements were used to determine melt fraction as a function of depth. Basaltic melt appears to have been generated by adiabatic decompression of dry peridotite with asthenospheric potential temperatures of 1340 ± 20 °C. Potential temperatures as high as 1365 °C were obtained for the Snake River Plain. For the youngest (i.e.

Subsurface fluid systems are important for chemical weathering, ore formation and thermal evolution of the crust. Changes in the dynamics and distribution of subsurface fluid flow systems are controlled by changes in global and regional terrestrial climate, tectonics, and elevation. This paper concerns the dating of changes in ancient subsurface hydrologic systems. However, direct dating of water-rock interaction is challenging because of the lack of appropriate materials to date and the more open and complex nature of subsurface flow regimes. Here, we explore the prospects of using U-Pb dating of petrified (silicified) wood as a means of quantifying continental paleo-hydrology. Oxidizing fluids, often of meteoric origin, tend to leach and mobilize U from the country rock, but when such waters contact organic-rich material, U can become reduced and immobilized, resulting in U-rich silicified wood. We present in situ laser ablation ICPMS analyses of U-Pb isotopes and trace elements in petrified wood from the Upper Triassic Chinle Formation (225–208 Myr) in the Petrified Forest National Park in Arizona (USA), allowing us to establish a generalized workflow for making meaningful paleo-hydrologic interpretations of the U-Pb systematics of silicified wood. Wood characterized by brownish colors and preservation of cellular structure have low Fe contents and positive Ce anomalies, indicating silicification in reducing environments and isolation in relatively reduced conditions after silicification, resulting in closed system behavior of U and Pb. Wood characterized by vivid colors (orange, red, etc.) and little to no preservation of cellular structure are much higher in Fe and exhibit negative Ce anomalies, indicating influence by more oxidized fluids. The brownish samples yield U-Pb ages clustered between 250 and 200 Ma with a peak coinciding with the time of deposition (~220 Ma), which indicates that fossilization largely took place almost immediately after deposition and that U-Pb in quartz faithfully retains the time of such fossilization. In contrast, the orangish-reddish-whitish samples yield younger U-Pb ages, defining distinct errorchron ages, which reflect subsequent generations of quartz crystallization. Scatter associated with errorchrons are likely due to local (mm- to cm-scale) U or Pb mobility or variable initial Pb composition. Distinct younger age peaks appear to correlate with the timing of regional unconformities associated with tectonic or epeirogenic uplift. We suggest that uplift and exhumation may initiate the onset of oxidizing fluid systems, resulting in leaching and transport of U from the surroundings, followed by subsequent generations of quartz precipitation. In summary, U-Pb dating of petrified wood or silicified organic material, has high potential for dating paleo-hydrologic events. However, due to complexities in terrestrial hydrologic systems, interpretations of U-Pb systematics must be informed by accompanying geochemical and textural observations.

This paper focuses on the depositional processes and environmental changes during initial marine flooding recorded in the lower Cambrian succession of the North China Platform in Shandong Province, China. In order to understand imbalance of accommodation and sediment supply in the initial stage of basin-fill, a detailed analysis of sedimentary facies was made for the lowermost siliciclastic deposits of the Liguan Formation. It reveals ten siliciclastic lithofacies in three large-scale outcrops (Jinhe, Anqianzhuang, and Zhangjiapo sections). These facies are grouped into four facies associations, representing siliciclastic foreshore-shoreface (S1), siliciclastic offshore (S2), distributary mouth bars (S3), and coastal plain (S4). The siliciclastic components occur in a linear belt, emanating from a major drainage system in the northeastern part of the platform. Deposition of siliciclastic sediments was largely controlled by regional topography of the unconformable surface and shoreline configuration as well as strong effect of waves and currents. With ensued rise in sea level and decrease in siliciclastic sediment supply, carbonate sediments prevailed, filling the accommodation created by epeirogenic subsidence and sediment loading.

The Sauk transgression was one of the most dramatic global marine transgressions in Earth history. It is recorded by deposition of predominantly Cambrian non-marine to shallow marine sheet sandstones unconformably above basement rocks far into the interiors of many continents. Here we use dating of detrital zircons sampled from above and below the Great Unconformity in the Grand Canyon region to bracket the timing of the Sauk transgression at this classic location. We find that the Sixtymile Formation, long considered a Precambrian unit beneath the Great Unconformity, has maximum depositional ages that get younger up-section from 527 to 509 million years old. The unit contains angular unconformities and soft-sediment deformation that record a previously unknown period of intracratonic faulting and epeirogeny spanning four Cambrian stages. The overlying Tapeats Sandstone has youngest detrital zircon ages of 505 to 501 million years old. When linked to calibrated trilobite zone ages of greater than 500 million years old, these age constraints show that the marine transgression across a greater than 300-km-wide cratonic region took place during an interval 505 to 500 million years ago—more recently and more rapidly than previously thought. We redefine this onlap as the main Sauk transgression in the region. Mechanisms for this rapid flooding of the continent include thermal subsidence following the final breakup of Rodinia, combined with abrupt global eustatic changes driven by climate and/or mantle buoyancy modifications. Extensive flooding of the North American continent during the Cambrian occurred more recently and more rapidly than previously thought, according to analyses of detrital zircons sampled from the Grand Canyon region.

Present-day drainage patterns in mountain regions are strongly affected by antecedent tectonic and geologic factors. In the mountains of eastern Lesotho, southern Africa, bedrock comprises flat-lying Jurassic basalts which have given rise to a relatively uniform initial land surface. Here, we present key morphometric measurements of river drainage patterns from this region, from six 4th order river basins, including principal river sinuosity, river long profiles and valley cross profiles, in order to evaluate geological controls on drainage evolution and the potential ages of river elements. Results show that there are highly variable spatial patterns of river morphometric properties, even between adjacent basins, despite identical geologies and altitudes across the region. However, northerly catchments show knickpoints, variable long profiles and have steep sided and V-shaped valley cross profiles. Southerly catchments have much smoother long profiles, no knickpoints, and concavo-convex valley cross profiles. There are also differences in river sinuosity values, both for the catchments as a whole and for reaches of different lengths within the catchments. These spatially varying river morphometric and drainage properties most likely are the long-preserved outcomes of epeirogenic forcing on the land surface (including tectonic uplift, mantle relaxation and rebound during the Cenozoic), and subtle long-term variations in climate from north to south across the region, including in precipitation and weathering.

U Pb detrital zircon and 40Ar 39Ar detrital sanidine dating of paleoriver deposits refines the timing of the mid-Cenozoic drainage reversal from NE- to SW-flowing rivers across the southern edge of the Colorado Plateau. NE-flowing paleorivers of the Mogollon Rim Formation were of multiple ages: ≤59.38 Ma for the Flying V outcrop and ≤37–33 Ma for other outcrops. These NE-flowing paleorivers were defeated by construction of the 38–23 Ma Mogollon–Datil volcanic field and extensional collapse of the Mogollon Highlands. The 37.6–21.8 Ma Whitetail Conglomerate of the Salt River paleocanyon records the transition from NE-flowing rivers to internal drainage that persisted from 30 to 14.67 Ma during continued extensional collapse. The SW-flowing proto-Salt River was established by about 12 Ma and flowed into Tonto Basin ~7 Ma. The Salt River extended its length to near Phoenix via basin spillover from the Tonto and Verde basins about 2.8 Ma and became established in its present path only in the past ~500 ka. Between 3.0 and 0.52 Ma, incision rates of the Salt River's headwaters have been steady at 95 m/Ma as calculated using the age and height of four far-traveled basalt runouts from the Springerville volcanic field. These incision rates contrast with 10 m/Ma rates for downstream areas near the Sentinel-Arlington volcanic field on the Gila River over the past 2.37 Ma. This 85 m/Ma of differential incision was a geomorphic response of headwater drainages to changes in base level (base level fall plus headwater uplift) that, at least in part, was a consequence of top-down integration of the Salt and Verde river systems via spillover. Neogene headwater uplift is proposed to have set the stage for and perhaps driven this downward integration by increasing river gradients, and progressive uplift in the past 3 Ma may help explain post-integration steady headwater incision. Surface uplift components include construction of the Springerville and San Francisco volcanic fields and related mantle-driven epeirogenic uplift of the southern rim of the Colorado Plateau. Long-term differential incision rates for the Salt River (85 m/Ma) are less than for the Colorado River system (140 m/Ma across Grand Canyon) suggesting west-up neotectonic tilting of the Colorado Plateau.

The hydrologic system in Jordan began its evolution with the regression of the Tethys during the Eocene and the rifting of Arabia from Africa. From that time onward Jordan lay on land. The rivers from Jordan and the Sirhan east of it flew into the Rift. On the Jordan land volcanism developed and was on and off active until sub-recent times. Flows of magma covered large areas in north and central Jordan. The uppermost hard layers of the deep valleys of the Yarmouk and the Mujib present evidence for their later erosion. The land to the east of the rift was low and in depressions lakes formed on the Jordan plateau, which began to rise less than half a Million years ago. Especially the Jafr and the Azraq Lakes developed a belt of green vegetation that attracted numerous animals which were hunted by early men. Tools for hunting and food preparation were produced from flint and assembled next to the former lake shores with time. The shape of these flint tools allows a coarse dating and documents the arrival of humans hundred thousand years ago and of modern men between 50,000 and 80,000 years ago. Great changes in the shape of the eastern Rift margin had occurred before Lake Lisan evolved and its rising water flooded the mouths of canyons for example of Wadi Hasa, Wadi Mujib and Wadi Zerka Ma’in. On former gravel fans into Lake Lisan of the Tabaqat Fahl first agriculture still in Neolithic times evolved as well as in Amman where people from Ain Ghazal planted crops like barley and peas, beans, lentils and chickpeas and domesticated sheep, goats and pigs. The existence of the highland lakes seems to have been of utmost importance to human migrations from Africa. Such lakes provided water and food for those humans in the Arid area of Jordan.

Next generation gravity missions are expected to improve the accuracy of temporal gravity models significantly. The periodic signals and trends retrieved by these missions are induced by mass redistribution in the Earth system, carrying essential information on dynamic processes in the atmosphere, cryosphere, continental hydrosphere, the oceans and the solid Earth. While temporal gravity signals induced by deep Earth's processes are commonly thought to lie below the observational threshold of satellite gravity missions, as one assumes them to be small in amplitude and restricted to the longest spatial and temporal scales, there exists evidence from the geologic record for rapid uplift and subsidence events at regional scales, especially along passive continental margins, related to flow in the underlying mantle. Here we explore novel mantle flow retrodictions for geodynamically plausible, compressible, high resolution Earth models with ≈ 670 million finite elements. These time-dependent Earth models link to geologic observables in the late Paleogene that can be tested independently, while at the same time indicating mantle flow induced geoid rates on the order of 5 μm/year, at spatial scales of 1000 km. We assess the signal retrievability of the modeled rates in closed-loop numerical simulations, with different satellite gravity retrieval mission assumptions, including GRACE, GRACE-FO and a next generation gravity mission. We find the modeled deep Earth signal to be on the edge of detectability, but coming into the range of detectability in future temporal gravity field solutions, suggesting the use of satellite gravity data to validate geodynamic Earth models. Importantly, the application of forward modeled dynamic mantle signals seems to be essential for improved de-aliasing and signal separation in future gravity missions.

Cratonic sedimentary basins are underlain by thick lithosphere and subside over hundreds of millions of years. The driving mechanism for these basins remains enigmatic due to the paucity of crustal-scale constraints. To address this shortcoming, an integrative study of the Parnaiba cratonic basin of NE Brazil is underway. We summarize field observations, well-log information, seismic reflection profiles and subsidence analyses with the objective of shedding light on possible basin-forming mechanisms. Lithological descriptions and borehole logs reveal a stratigraphic succession that consists of interbedded shallow marine and continental deposits. On seismic reflection profiles, this succession is divided into packages of relatively undisturbed reflections bounded by basin-wide disconformities. These disconformities are manifest as bright, rugose reflections that probably represent buried palaeo-landscapes. Backstripped and water-loaded subsidence curves calculated from boreholes distributed throughout the basin show that tectonic subsidence decreases exponentially over c. 350 Ma. A simple model suggests that this subsidence pattern agrees with a thermal time constant of 70–100 Ma, placing a significant constraint on the likely basin-forming mechanism. This background trend is punctuated by minor increases in subsidence that follow basin-wide erosional disconformities. These departures could be indicative of transient epeirogenic uplift events caused by changing patterns of dynamic topography.

A family of geophysical lineaments have been identified in ∼15,000 km 2 in central Kerala between 9°30′N to 10°45′N and 76°00′E to 77°30′E, integrating geophysical data with geological and geomorphological features. The characteristics of these lineaments in the magnetic and gravity fields and their derivatives have been analysed. The evolution of the lineaments has been traced to the temporal phases of global evolution of the region. A group of these faults have formed by reactivation of the deep-seated distensional fractures associated with and accompanying dyke emplacements during the episodic breakup of Gondwana at ∼90 and 65 Ma under distinctive mantle thermal regimes. It is possible that reactivation of these distensional faults may have started during the cooling interval of time between the two distensions in the 90 and 65 Ma and post 65 Ma periods and later in the Cenozoic, when the lineaments were enlarged to their present dimension, possibly under the influence of forces that led to the uplift of the western Ghats. These may extend down to the crust-mantle interface. A cluster of younger geophysical lineaments has been generated by reactivation along the weak planes of transformation of the charnockitic rocks of the Precambrian. They seem to have a strike-slip character. They are devoid of any dyke association and were formed on a cold crust. They may be confined to the upper-middle crust. They were generated in the high intensity intra-plate palaeo-stress fields of the triple forces arising from (1) the back-thrust from the Himalayan Collision; (2) the impact of epeirogenic forces and related isostatic uplift of the Western Ghats and (3) the flexural isostatic uplifts due to surface loads of late Mesozoic basaltic lavas and Cenozoic sedimentation in the coastal rifted basins in late Cenozoic, probably in the time span of 20 Ma to the present, when the palaeostress fields were most intense.

Erosional unconformity surfaces are key indicators for the variations in eustatic sea level, ocean dynamics and climatic conditions which significantly affect depositional environments of sedimentary successions. Using a dense grid of 2D seismic data, we present new evidence from a frontier basin, the offshore Durban Basin, of a mid-Miocene age erosional unconformity that can be correlated with analogous horizons around the entire southern African continental margin. In the Durban Basin, this unconformity is typified by the incision of a mixed carbonate-siliciclastic wedge and ramp margin by a series of submarine canyons. Epeirogenic uplift of southern Africa characterised this period, with erosion and sediment bypass offshore concomitant with increases in offshore sedimentation rates. Although epeirogenic uplift appears to be the dominant mechanism affecting formation of the identified sequence boundary, it is postulated that an interplay between global eustatic sea-level fall, expansion of the east Antarctic ice sheets, and changes in deep oceanic current circulation patterns may have substantially contributed to erosion during this period.

Across much of North America, the contact between Precambrian basement and Paleozoic strata is the Great Unconformity, a surface that represents a >0.4 b.y.-long hiatus. A digital elevation model (DEM) of this surface visually highlights regional-scale variability in the character of basement topography across the United States cratonic platform. Specifically, it delineates Phanerozoic tectonic domains, each characterized by a distinct structural wavelength (horizontal distance between adjacent highs) and/or structural amplitude (vertical distance between adjacent lows and highs). The largest domain, the Midcontinent domain, includes long-wavelength epeirogenic basins and domes, as well as fault-controlled steps. The pronounced change in land-surface elevation at the Rocky Mountain Front coincides with the western edge of the Midcontinent domain on the basement DEM. In the Rocky Mountain and Colorado Plateau domains, west of the Rocky Mountain Front, structural wavelength is significantly shorter and structural amplitude significantly higher than in the Midcontinent domain. The Bordering Basins domain outlines the southern and eastern edges of the Midcontinent domain. As emphasized by the basement DEM, several kilometers of structural relief occur across the boundary between these two domains, even though this boundary does not stand out on ground-surface topography. A plot of epicenters on the basement DEM supports models associating intraplate seismicity with the Midcontinent domain edge. Notably, certain changes in crustal thickness also coincide with distinct changes in basement depth.

This paper presents a new synthesis for the late Cenozoic tectonic, paleogeographic, and geomorphologic evolution of the southern Sierra Nevada and adjacent eastern San Joaquin Basin. The southern Sierra Nevada and San Joaquin Basin contrast sharply, with the former constituting high-relief basement exposures and the latter constituting a Neogene marine basin with superposed low-relief uplifts actively forming along its margins. Nevertheless, we show that Neogene basinal conditions extended continuously eastward across much of the southern Sierra Nevada, and that during late Neogene–Quaternary time, the intra-Sierran basinal deposits were uplifted and fluvially reworked into the San Joaquin Basin. Early Neogene normal-sense growth faulting was widespread and instrumental in forming sediment accommodation spaces across the entire basinal system. Upon erosion of the intra-Sierran basinal deposits, structural relief that formed on the basement surface by the growth faults emerged as topographic relief. Such “weathered out” fossil fault scarps control much of the modern southern Sierra landscape. This Neogene high-angle fault system followed major Late Cretaceous basement structures that penetrated the crust and that formed in conjunction with partial loss of the region’s underlying mantle lithosphere. This left the region highly prone to surface faulting, volcanism, and surface uplift and/or subsidence transients during subsequent tectonic regimes. The effects of the early Neogene passage of the Mendocino Triple Junction were amplified as a result of the disrupted state of the region’s basement. This entailed widespread high-angle normal faulting, convecting mantle-sourced volcanism, and epeirogenic transients that were instrumental in sediment dispersal, deposition, and reworking patterns. Subsequent phases of epeirogenic deformation forced additional sediment reworking episodes across the southern Sierra Nevada–eastern San Joaquin Basin region during the late Miocene break-off and west tilt of the Sierra Nevada microplate and the Pliocene–Quaternary loss of the region’s residual mantle lithosphere that was left intact from the Late Cretaceous tectonic regime. These late Cenozoic events have left the high local-relief southern Sierra basement denuded of its Neogene basinal cover and emergent immediately adjacent to the eastern San Joaquin Basin and its eastern marginal uplift zone.

The Western Ghats is one of the largest escarpments on earth, containing Reunion plume derived Deccan Traps, it is an excellent example to probe epeirogenic uplift, extension and subsidence in volcanic continental margins. The most continuous unbiased stratigraphic section of basalt down to the basement within a 1250 m drill hole of the Continental Scientific Deep Drilling Project is a valuable resource to investigate the above aspects. The flows across the entire drill core are geologically subaerial in character with basement exposed ~300 m below the mean sea level; they clearly display more evolved compositions from primary melts of mantle in terms of petrology, and only a single geomagnetic polarity transition in palaeomagnetic data. These results, combined with existing geological and geophysical data, constitute a multi-method approach that demonstrates (a) igneous underplating caused uplift prior to frequently suggested flexural isostasy (b) plume impact and eruption are near-simultaneous and extension/rifting essentially followed soon after volcanism and (c) lithosphere beneath the continental margin, while returning to normal temperatures following the Seychelles-India breakup, experienced thermal collapse and subsidence causing slumping of basalt basement below sea level.

Cambrian siliciclastic sequences along the Dead Sea Transform (DST) margin in southern Israel and southern Jordan host both detrital fluorapatite [D-apatite] and U-rich authigenic carbonate-fluorapatite (francolite) [A-apatite]. D-apatite and underlying Neoproterozoic basement apatite yield fission-track (FT) data reflecting Palaeozoic–Mesozoic sedimentary cycles and epeirogenic events, and dispersed (U–Th–Sm)/He (AHe) ages. A-apatite, which may partially or completely replace D-apatite, yields an early Miocene FT age suggesting formation by fracturing, hydrothermal fluid ascent and intra-strata recrystallisation, linked to early DST motion. The DST, separating the African and Arabian plates, records ~105 km of sinistral strike-slip displacement, but became more transtensional post-5 Ma. Helium diffusion measurements on A-apatite are consistent with thermally activated volume diffusion, indicating Tc ~52 to 56 ± 10°C (cooling rate 10°C/Ma). A-apatite AHe data record Pliocene cooling (~35 to 40°C) during the transtensional phase of movement. This suggests that timing of important milestones in DST motion can be discerned using A-apatite low-temperature thermochronology data alone.

Evidence of kilometre scale uplift and subsidence at locations remote from any recognised plate boundaries, the existence of mega-sequences of post-rift marine sediments over widespread intra-cratonic areas, and the consideration that pulses of deposition display a clear periodicity and synchronicity over widely dispersed spatial domains, remain largely unresolved issues within current geological theory. While the exact timing of uplift and erosion associated with major unconformities are difficult to assess, the age of sediments immediately above provide vital temporal markers for the onset of subsidence and associated sea level rise. By reconsidering the much studied sedimentary sequences of the Grand and Bryce Canyon areas the following will show that the at least over the Phanerozoic eon the initiation of new pulses of deposition occur at times when earth climate is emerging from ice-house to hot-house conditions. Furthermore, the recorded periods in which global occurrences of epeirogeny have occurred will be shown to correlate closely with the end of hot-house periods and the onset of ice-house global climate conditions. Finally, some tentative thermo-geodynamic explanations for this apparent causal link between global climate and vertical tectonics will be suggested.

Boris Lichkov, an outstanding scientist of the first half of the XXth century, worked successfully on a number of basic problems of Earth sciences, such as origin and evolution of deserts, epeirogenic crustal movements correlation of marine and alluvial terraces in the context of the Black Sea formation, geochronology of continental nuclea, such as the “ancient crown of Asia” by E. Suess (Baikalian orogen of Southern Siberia), glaciations and formation of great alluvial plains

This paper documents a multi-stage incision and denudation history for the Little Colorado River (LCR) region of the southwestern Colorado Plateau over the past 70 Ma. The first two pulses of denudation are documented by thermochronologic data. Differential Laramide cooling of samples on the ­Mogollon Rim suggests carving of 70–30 Ma paleotopography by N- and E-flowing rivers whose pathways were partly controlled by strike valleys at the base of retreating Cretaceous cliffs. A second pulse of denudation is documented by apatite (U-Th)/He dates and thermal history models that indicate a broad LCR paleovalley was incised 25–15 Ma by an LCR paleoriver that flowed northwest and carved an East Kaibab paleovalley across the ­Kaibab uplift. Lacustrine strata of the lower Bidahochi Formation were deposited 16–14 Ma in the LCR paleovalley in a closed basin playa or marsh with a valley center near the modern LCR. There is a hiatus in the depositional record in the LCR valley from 12 to 8 Ma followed by aggradation of the 8–6 Ma fluvial upper Bidahochi Formation. Interlayered 8–6 Ma maar basalts that interacted with groundwater mark local base level for upper Bidahochi fluvial deposits; this was also a time of increased groundwater flow to Hualapai Limestone at the western edge of the Colorado Plateau. The paleo–base level in the central LCR valley remained stable (∼1900 m modern elevation) from 16 to 6 Ma. The third pulse of regional incision and denudation, most recent and ongoing, started after integration of the Colorado River (CR) through Grand Canyon. Thermochronology from Marble Canyon indicates that early CR integration took place across the Vermillion Cliffs at Lees Ferry after 6 Ma. The elevation of the paleoconfluence between the LCR and CR at 5–6 Ma is poorly constrained, but earliest CR integration is hypothesized to have reoccupied the East Kaibab paleocanyon. In the upper LCR drainage, topographically inverted basalt ­mesas have elevations and K-Ar dates indicating a transition from aggradation to incision ca. 6 Ma followed by semi-steady incision of 20–40 m/Ma. In the lower LCR, incision accelerated to 120–170 m/Ma after 2 Ma as indicated by 40 Ar/ 39 Ar dating of basalt, ash-fall, and detrital sanidine. A 1.993 ± 0.002 Ma sanidine age for a tuff in the White Mesa alluvium provides a breakthrough for LCR and CR incision studies. Post–2 Ma differential incision magnitudes (and rates) in the lower LCR and at the LCR-CR confluence were 280–320 m (140–160 m/Ma), about three times greater than the 40–80 m (20–40 m/Ma) in the LCR headwaters. The proposed mechanisms driving overall post–6 Ma differential incision of the LCR involve headwater uplift associated with the Hopi Buttes and Springer­ville volcanic fields plus base-level fall caused by CR integration to the Gulf of California. A proposed mechanism to explain the accelerated post–2 Ma differential incision in the central and lower LCR valley, but not in the head­waters, involves mantle-driven epeirogenic uplift due to NE-migrating vol­canism associated with the San Francisco volcanic field. Tectonically driven differential surface uplift mechanisms were likely amplified by changes toward more erosive climate at ca. 6 Ma and ca. 2 Ma.

Mantle plumes have been proposed to exert a first-order control on the morphology of Earth's surface. However, there is little consensus on the lifespan of the convectively supported topography. Here, we focus on the Cenozoic uplift and exhumation history of the British Isles. While uplift in the absence of major regional tectonic activity has long been documented, the causative mechanism is highly controversial, and direct exhumation estimates are hindered by the near-complete absence of onshore post-Cretaceous sediments (outside Northern Ireland) and the truncated stratigraphic record of many offshore basins. Two main hypotheses have been developed by previous studies: epeirogenic exhumation driven by the proto-Iceland plume, or multiple phases of Cenozoic compression driven by far-field stresses. Here, we present a new thermochronological dataset comprising 43 apatite fission track (AFT) and 102 (U–Th–Sm)/He (AHe) dates from the onshore British Isles. Inverse modelling of vertical sample profiles allows us to define well-constrained regional cooling histories. Crucially, during the Paleocene, the thermal history models show that a rapid exhumation pulse (1–2.5 km) occurred, focused on the Irish Sea. Exhumation is greatest in the north of the Irish Sea region, and decreases in intensity to the south and west. The spatial pattern of Paleocene exhumation is in agreement with the extent of magmatic underplating inferred from geophysical studies, and the timing of uplift and exhumation is synchronous with emplacement of the plume-related British and Irish Paleogene Igneous Province (BIPIP). Prior to the Paleocene exhumation pulse, the Mesozoic onshore exhumation pulse is mainly linked to the uplift and erosion of the hinterland during the complex and long-lived rifting history of the neighbouring offshore basins. The extent of Neogene exhumation is difficult to constrain due to the poor sensitivity of the AHe and AFT systems at low temperatures. We conclude that the Cenozoic topographic evolution of the British Isles is the result of plume-driven uplift and exhumation, with inversion under compressive stress playing a secondary role.

Peninsular India is a cratonic region with asymmetric relief manifest by eastward tilting from the 1.5 km high Western Ghats escarpment toward the floodplains of eastward-draining rivers. Oceanic residual depth measurements on either side of India show that this west-east asymmetry is broader scale, occurring over distances of >2,000 km. Admittance analysis of free-air gravity and topography shows that the elastic thickness is 10 ±3 km, suggesting that regional uplift is not solely caused by flexural loading. To investigate how Indian physiography is generated, we have jointly inverted 530 river profiles to determine rock uplift rate as a function of space and time. Key erosional parameters are calibrated using independent geologic constraints (e.g. emergent marine deposits, elevated paleosurfaces, uplifted lignite deposits). Our results suggest that regional tilt grew at rates of up to 0.1 mm a– 1 between 25 Ma and the present day. Neogene uplift initiated in the south and propagated northward along the western margin. This calculated history is corroborated by low-temperature thermochronologic observations, by sedimentary flux of clastic deposits into the Krishna-Godavari delta, and by sequence stratigraphic architecture along adjacent rifted margins. Onset of regional uplift predates intensification of the Indian monsoon at 8 Ma, suggesting that rock uplift rather than climatic change is responsible for modern-day relief. A positive correlation between residual depth measurements and shear wave velocities beneath the lithosphere suggests that regional uplift is generated and maintained by temperature anomalies of ±100°C within a 200 ±25 km thick asthenospheric channel. This article is protected by copyright. All rights reserved.

We have studied detrital-zircon U-Pb age spectra and conglomerate clast populations from Neogene–Quaternary siliciclastic and volcaniclastic strata of the southeastern San Joaquin Basin, as well as a fault-controlled Neogene basin that formed across the southernmost Sierra Nevada; we call this basin the Walker graben. The age spectra of the detrital-zircon populations are compared to a large basement zircon age data set that is organized into age populations based on major drainage basin geometry of the southern Sierra Nevada and adjacent ranges. We find a direct sediment provenance and dispersal link for much of the Neogene between the Walker graben and the southeastern San Joaquin Basin. In early to middle Miocene time, this link was accented by the delivery of volcaniclastic materials into the southeastern Basin margin from the Cache Peak volcanic center that was nested within the Walker graben. In late middle Miocene through early Pleistocene time, this linkage was maintained by a major fluvial system that we call the Caliente River, whose lower trunk was structurally controlled by growth faults along the Edison graben, which breached the western wall of the Walker graben. The Caliente River redistributed into the southeastern San Joaquin Basin much of the ∼2 km of volcaniclastic and siliciclastic strata that filled the Walker graben. This sediment redistribution was forced by a regional topographic gradient that developed in response to uplift along the eastern Sierra escarpment system. The Caliente River built a fluvial-deltaic fan system that prograded northwestward across the lower trunk of the Kern River and thereby deflected the Kern drainage flux of sediment into the Basin edge northward. In mainly late Miocene time, turbidites generated primarily off the Caliente River delta front built the Stevens submarine fan system of the southeastern and central areas of the San Joaquin Basin. In late Quaternary time, 1–1.8 km of Caliente River–built strata were eroded as an epeirogenic uplift that we call the Kern arch emerged along the southeastern Basin margin, in response to underlying mantle lithosphere removal. The sediment that was eroded off the arch was redistributed mainly into the Maricopa and Tulare sub-basins that are located to the southwest and northwest, respectively, of the arch.

Apatite fission track (AFT) and (U-Th)/He (AHe) thermochronometry data are reported and used to unravel the exhumation history of crystalline basement rocks from the elevated (>1000 m a.s.l.), but low relief Tanzanian Craton. Coeval episodes of sedimentation documented within adjacent Paleozoic to Mesozoic basins of southern Tanzania and the Congo basin of the Democratic Republic of Congo (DRC) indicate that most of the cooling in the basement rocks in Tanzania was linked to erosion. Basement samples were from an exploration borehole located within the craton, and up to 2200 m below surface. Surface samples were also analysed. AFT dates range between 317 ± 33 Ma and 188 ± 44 Ma. Alpha (Ft)-corrected AHe dates are between 433 ± 24 Ma and 154 ± 20 Ma. Modelling of the data reveals two important periods of cooling within the craton; one during the Carboniferous-Triassic (340 -220 Ma) and a later, less well constrained episode, during the late Cretaceous. The later exhumation is well detected proximal to the East African Rift (70 Ma). Thermal histories combined with the estimated geothermal gradient of 9 °C/km constrained by the AFT and AHe data from the craton and a mean surface temperature of 20 °C, indicate removal of up to 9 ± 2 km of overburden since the end-Paleozoic. The correlation of erosion of the craton and sedimentation and subsidence within the Congo basin in the Paleozoic may indicate regional flexural geodynamics of the lithosphere due to lithosphere buckling induced by far-field compressional tectonic processes, and thereafter through deep mantle upwelling and epeirogeny tectonic processes.

Onshore drilling by Ocean Drilling Program (ODP) Legs 150X and 174AX and offshore drilling by Integrated Ocean Drilling Program (IODP) Expedition 313 provides continuous cores and logs of seismically imaged Lower to ­Middle Miocene sequences. We input ages and paleodepths of these sequences into one-dimensional backstripping equations, progressively accounting for the effects of compaction, Airy loading, and thermal subsidence. The resulting difference between observed subsidence and theoretical thermal subsidence provide relative sea-level curves that reflect both global average sea level and non-thermal subsidence. In contrast with expectations, backstripping suggests that the relative sea-level maxima in proximal onshore sites were lower than correlative maxima on the shelf. This requires that the onshore New Jersey coastal plain has subsided relative to the shelf, which is consistent with models of relative epeirogeny due to subduction of the Farallon plate. These models predict subsidence of the coastal plain relative to the shelf. Although onshore and offshore sea-level estimates are offset by epeirogeny, the ampli­tude of million-year–scale Early to Middle Miocene sea-level changes seen at the New Jersey margin is generally 5–20 m and occasionally as great as 50 m. These events are interpreted to represent eustatic variations, because they occur on a shorter time frame than epeirogenic influences. Correction for epeiro­genic effects largely reconciles differences between onshore and offshore rela­tive sea-level estimates and suggests that backstripping provides a testable eustatic model for the Early to Middle Miocene.

Cratons are conventionally assumed to be areas of long-term stability. However, whereas Precambrian basement crops out across most of the Baltic Shield, Palaeozoic and Mesozoic sediments rest on basement in southern Sweden, and thus testify to a complex history of exhumation and burial. Our synthesis of published stratigraphic landscape analysis and new apatite fission-track analysis data reveals a history involving five steps after formation of the extremely flat, Sub-Cambrian Peneplain. (1) Cambrian to Lower Triassic rocks accumulated on the peneplain, interrupted by late Carboniferous uplift and exhumation. (2) Middle Triassic uplift removed the Palaeozoic cover along the south-western margin of the shield, leading to formation of a Triassic peneplain with a predominantly flat relief followed by deposition of Upper Triassic to Lower Jurassic rocks. (3) Uplift that began during the Middle Jurassic to earliest Cretaceous caused denudation leading to deep weathering that shaped an undulating, hilly relief that was buried below Upper Cretaceous to Oligocene sediments. (4) Early Miocene uplift and erosion produced the South Smaland Peneplain with scattered hills. (5) Early Pliocene uplift raised the Miocene peneplain to its present elevation leading to reexposure of the sub-Cretaceous hilly relief near the coast. Our results thus provide constraints on the magnitude and timing of episodes of deposition and removal of significant volumes of Phanerozoic rocks across the southern portion of the Baltic Shield. Late Carboniferous, Middle Triassic and mid-Jurassic events of uplift and exhumation affected wide areas beyond the Baltic Shield, and we interpret them as epeirogenic uplifts accompanying fragmentation of Pangaea, caused by accumulation of mantle heat beneath the supercontinent. Early Miocene uplift affected north-west Europe but not East Greenland, and thus likely resulted from compressive stresses from an orogeny on the Eurasian plate. Early Pliocene uplift related to changes in mantle convection and plate motion affected wide areas beyond North-East Atlantic margins.

Epeirogenic histories of highland areas have confounded earth scientists for decades, as there are few sedimentary records of paleoelevation in eroding highlands. For example, mechanisms that have led to the high elevations of the Hangay Mountains in central Mongolia are not clear, nor is it well understood how the epeirogenic history of central Mongolia is connected to that of a broader region of high elevation that extends hundreds of kilometers to the north, east, and west. However, preserved basaltic lava flows record paleoelevation in the size distributions of vesicles at the tops and bottoms of flow units. As an initial step toward better understanding the tectonics of this part of Asia, we collected and analyzed samples from several basaltic lava flows from throughout the Hangay Mountains to use as a paleoaltimeter on the basis of lava flow vesicularity. Samples were dated and scanned with x-ray tomography to provide quantitative information regarding their internal vesicle size distributio...

The early Silurian (Llandovery) Gondwanan South Polar ice sheet experienced episodes of ice retreat and re-advance. Marine base level curves constructed for the interval are widely assumed to provide a record of the associated glacioeustasy. In revealing a series of progradational sequences (progrades) bounded by flooding surfaces, recent work on the Type Llandovery succession in mid Wales (UK) has provided an opportunity to test this hypothesis. The grouping of these progrades into three composite sequences underpins the construction of both low order (small amplitude, high frequency) and high order (large amplitude, low frequency) base level movement curves. Revised biostratigraphical datasets for the type succession permit the accurate dating of base level events. The composite sequences record progradational acmes in the acinaces, lower convolutus and upper sedgwickii-halli graptolite biozones. A series of transgressions that postdate the Hirnantian glacial maximum culminated in an upper persculptus Biozone high-stand. Maximum flooding events also occurred during the revolutus and lower sedgwickii biozones, and the base of the early Telychian guerichi Biozone also marked the onset of a pronounced deepening. A review of 62 published datasets, including global and other regional base level curves, records of glacial activity, isotope data, patterns of facies and faunal flux and putative climate models, permits an evaluation of the origins of these local base level events. The concept of a Eustasy Index is introduced and shows that the impacts of global sea level movements can only be demonstrated within narrow ‘eustatic windows’ coincident with times of ice sheet collapse. At other times, the geometry of Llandovery area progrades reflects their accumulation across a faulted basin margin where, during periods of slow ice sheet advance, epeirogenic processes outstripped sea level movements as the dominant forcing factors. Increased levels of Telychian subsidence at first enhanced and then overwhelmed the influence of glacioeustasy as part of the region's response to the north European Scandian deformation.

Hydrocarbons have recently been discovered in Upper Triassic to Middle Jurassic siliciclastic reservoirs in the Rub' Al-Khali basin in Saudi Arabia. The reservoirs fill accommodation space created by Triassic and early Jurassic crustal-scale basins on the order of 100 km (62 mi) in wavelength and hundreds of meters in depth. These basins are separated by highs that are interpreted as crustal-scale epeirogenic folds. Lithologies include well-sorted quartz arenites deposited in shallow-marine, shoreface, and fluviodeltaic settings. These sequences can be correlated across the basin to extensive escarpment outcrops south of Riyadh and beyond Saudi Arabia into well-documented equivalents elsewhere in the Middle East and East Africa. The gross architecture of the interval is imaged on reflection seismic, showing clinoformal geometries and onlap onto the Triassic structured surface. Geochemistry of tested fluids indicates a type III kerogen source. The simplest interpretation is that the system is self-sourcing hydrocarbons from interbedded coaly material that is observed in the wells and at outcrop. Reservoir pressures are anomalously low relative to the overlying carbonate reservoir systems. These low pressures are interpreted to indicate lateral communication from the Rub' Al-Khali basin westward to outcrop, in contrast with the overlying carbonate fairways that are known to contain facies boundaries that trend across the regional dip. Onlapping geometries in the siliciclastic fairway combine with Cretaceous and Cenozoic compressional structures to create combined structural-stratigraphic traps.

Ordovician conodont studies have revealed a depositional hiatus extending from the late Floian to early Darriwilian on the North China Platform. Recognition of this widespread gap entails revision of the original concept of the Huaiyuan Epeirogeny, with definition of two distinct regional tectonic events: Event 1, which initiated this hiatus, and a subsequent Event 2 that was responsible for terminating Early Palaeozoic sedimentation in the region from the late Katian. The timing of these two events partly coincides with widely recognized eustatic sea-level falls, and separates Ordovician sedimentation into two episodes that can be broadly correlated with eustatic sea-level rises. In combination with these sea-level changes, the Huaiyuan Epeirogeny played a decisive role in shaping and controlling Ordovician sedimentation and sequence stratigraphic architecture on the North China Platform. Lower Ordovician carbonates were deposited during an apparent regression (decreasing accommodation space), resulting from rapid sediment accumulation exceeding the overall rate of basement subsidence and eustatic sea-level rise. Sedimentation ceased in the middle to late Floian when basement uplift commenced in the south and extended northward to affect the entire platform. The diachronous top surface of the Lower Ordovician succession reflects extensive erosion that is most pronounced in the south and southwest parts of the platform where the disconformity surface cut down into Tremadocian (or even upper Cambrian) strata. Deposition of the younger sequence (Darriwilian to Katian) was the result of the interplay between rejuvenated basement subsidence and the late Middle Ordovician eustatic sea-level rise. Event 2, which was initially coupled with eustatic sea-level fall induced by the end-Ordovician glaciations, terminated Ordovician deposition in the region with the top of the Ordovician marked by an unconformity, representing a hiatus of some 122 Ma extending from latest Ordovician to latest Mississippian.

The paper is a continuation of studies of the Earth's crust neotectonic movements within the northwestern part of the Kola region. New radiocarbon data of the lake bottom sediments in the Tuloma River valley allowed to modify diagram of the relative uplift lines of the Earth surface in the north-western part of the Kola region and to compare them with previously constructed epeirogenic spectra of coastal landforms for the study area. The dynamics and nature of the area uplift have been established and the dating of the ancient shorelines within the Tuloma River valley and the Kola Bay of the Barents Sea during the Holocene has been carried out. Ключевые слова: неотектоника, донные отложения озер, древние береговые образования, голоцен, Кольский регион.

The origin of Iberia's topography is examined by combining gravity, magmatic, topographic and seismological observations with geomorphic considerations. We have four principal results. First, highest coherence between free‐air gravity and topography is at wavelengths ≲250 km where admittance indicates that elastic thickness of Iberia's plate is 20 ± 3 km. These results imply that flexural and sub‐plate support of Iberian topography could be expressed at wavelengths of O(100) km. Secondly, P‐to‐S receiver functions and simple isostatic calculations indicate that whilst crustal thickness variations and flexural loading (e.g. as a result of plate shortening) partially explain the elevation of Pyrenean, Betics, Cantabrian, Spanish Central System and Iberian Chain topography, they fail to explain the elevation of large parts of Iberia. Thirdly, a new full waveform shear wave tomographic model and velocity to temperature conversions suggest that the asthenosphere beneath Iberia is anomalously slow and has excess temperatures of up to 162 ± 14°C. Simple isostatic calculations indicate asthenospheric support of topography of up to 1 km. Neogene‐Recent (∼23–0 Ma) extrusive magmatism (e.g. Calatrava, Catalan) sit atop many of the slow shear wave velocity anomalies. Finally, biostratigraphic data, combined with inversion of 3217 river profiles, show that most of Iberia's topography grew during the last ∼30 Ma at rates of up to 0.3 mm yr−1. Best‐fitting theoretical rivers have a low residual rms misfit (=0.96) and calculated uplift is consistent with an independent inventory of stratigraphic and biostratigraphic observations. We suggest that Neogene‐Recent growth of most of central Iberia's topography was a result of asthenospheric support.

The lower Middle Cambrian of Scandinavia is reviewed and subjected to sequence stratigraphical analysis. Sequences are defined as transgressive–regressive depositional units bounded by maximum regressive surfaces and their correlative conformities. The lower Middle Cambrian forms part of a 2nd order sequence, labelled Cambrian Supersequence 3 (CS-3). It is bounded at the base by a regional unconformity ascribed to the so-called Hawke Bay Event, the focus of this paper. CS-3 comprises at least four 3rd order sequences, but the upper part above the Triplagnostus gibbus Zone has not been analysed as yet and the upper supersequence boundary remains undefined for the time being. The oldest sequence of CS-3 is seemingly of Early Cambrian age. There are numerous T/R cycles in the Acadoparadoxides oelandicus Superzone, here ranked as subsequences (4th order sequences), but a classification as 3rd order cycles of some of these is possible, thereby increasing the number of prospective sequences in CS-3. The high frequency sea-level fluctuations are reminiscent of glacioeustasy and the early Mid Cambrian possibly represents a c. 5 Ma long glacial interval with overall low global sea-level and frequent sea-level changes. The Hawke Bay Event, as identified in Scandinavia, primarily reflects an extensive and long-lasting epeirogenic uplift of western Baltica, and using the term event is a misnomer. The uplift is informally referred to as the Hawke Bay uplift. However, the initial rapid uplift in the latest Early Cambrian coincided with ≥ 100 m eustatic lowering of the sea-level, leading to simultaneous regression in the East Baltic area and elsewhere. This forced regression is assumed representing the Hawke Bay Event s.str. In Estonia–Latvia–Lithuania, the unconformity separating the Kibartian and Deimenian regional stages signals the Hawke Bay regression. The Hawke Bay uplift gradually and differentially subsided during the early Mid Cambrian, starting in the Oland–Gotland area, and the collapse then slowly progressed westwards and southwestwards. Subsidence also advanced from western Norway and eastwards whereas the western margin of Baltica apparently remained uplifted throughout the late Mid Cambrian to earliest Ordovician. In central Scandinavia, the last traces of the Hawke Bay uplift eventually disappeared during the Acidusus atavus Chron. As a result the Hawke Bay unconformity represents a greater hiatus in central and southernmost Scandinavia where the uplift persisted for a longer time (locally up to c. 6 Ma), causing long-lasting non-deposition associated with minor erosion. The epeirogenic uplift is inferred to have been triggered by stress-induced isostasy linked to major plate-tectonic adjustments, possibly the onset of subduction in the adjacent Iapetus Ocean or cessation of the Timanide collision, or both. A series of palaeogeographical maps is constructed for the Middle Cambrian of Scandinavia and adjacent countries. Subcrop and onlap maps of the Hawke Bay unconformity, as well as isopach maps for Middle Cambrian formations are also shown. The elongate land area that straddled the axis of the Scandinavian Peninsula during the Early Cambrian disappeared after subsidence of the Hawke Bay uplift and a new basin configuration was established. This had an overall gentle westwardly sloping sea floor delimited by a broad uplift along the western Baltica margin that formed a submarine sill from the medial Mid Cambrian and onwards. The sill, which eventually disappeared in the later part of the Tremadocian, restricted exchange of water masses and the deeper parts of the epicontinental sea became characterized by dysoxic and anoxic conditions. The resulting organic-rich deposit is referred to as Alum Shale. The sea-level rose eustatically after the terminal Early Cambrian Hawke Bay lowstand (in a strict sense) to reach a temporary highstand during the later part of the A. oelandicus Superchron. It then fell abruptly again at the end of the A. oelandicus Superchron and remained low in the earliest part of the Paradoxides paradoxissimus Superchron. Overall, on a 2nd order scale, the sea-level remained low during the early Mid Cambrian and as a result, the clastic supply was relatively high. The principal sediment supply was from the east; initially minor amounts of clastics were also supplied from the uplifted parts of Scandinavia but overall erosion of the uplifted area was limited, probably due to the extremely flat topography. The high clastic influx from the east resulted in progradation, progressively shifting the coastline westwards. Eventually it reached a position roughly corresponding to the present-day east coast of mainland Sweden. In addition to the initial Hawke Bay regression (s.str,) in the latest Early Cambrian significant forced regressions occurred at the end of the Acadoparadoxides pinus – Pentagnostus praecurrens Chron (here named the Faludden Lowstand) and in the T. gibbus Chron (the Mid-gibbus Lowstand). Several unnamed sea-level lowerings also occurred in the A. pinus – P. praecurrens Chron. A rapid, major sea-level rise at the beginning of the A. pinus – P. praecurrens Chron, estimated at c. 60–70 m, is named the Oelandicus Drowning. Fast sea-level rises at the start and in the middle of the T. gibbus Chron are referred to as the Forsemolla and Exsulans drownings, respectively. From the middle of the T. gibbus Chron onwards into the A. atavus Chron there was a major sea-level rise (Atavus Highstand). This latter rise is estimated at c. 100 m and for the first time the sea-level became as high or higher than it was just prior to the Hawke Bay regression. The associated transgression shifted the coastline some 500–700 km eastwards and from then onwards, extreme clastic starvation prevailed in the epicontinental sea covering Scandinavia. Simultaneously, the mid-shelf became a net sedimentary bypass zone, either due to regular outboard transport of sediment during storms or due to recurrent erosive events associated with sea-level lowstands. Two Mid Cambrian depositional phases are recognized, termed Depositional Phases 3 and 4. Depositional Phase 3 encompasses the transient increase in sedimentary supply during the early Mid Cambrian sea-level lowstand, whereas DP4 covers the strongly starved conditions and widespread dysoxia from the A. atavus Chron onwards associated with high sea-level. A gradual expansion of the oxygen minimum zone during the Mid Cambrian developed independently of the rising sea-level and is suggestive of a stratified water column, presumably created by silled basin conditions. It is likely, however, that the general ‘background’ oxygen level in the oceans also was low, perhaps due to sluggish global circulation in a greenhouse world. Two new regional stages, the Bodan and Almbackenian, are introduced for the Middle Cambrian A. oelandicus and P. paradoxissimus superzones of Scandinavia, respectively. The base of the Middle Cambrian Timofeevia lancare acritarch assemblage zone is located within the upper part of the A. pinus – P. praecurrens trilobite Zone. The T. gibbus trilobite Zone is informally subdivided into a lower Paradoxides jemtlandicus subzone and an upper Bailiaspis dalmani subzone.

Africa’s modern Zambezi is proposed as an example of a major extant river system, which archives the tectonic events that assembled and then fragmented a supercontinent. The Zambezi and an earlier Karoo river system, (here designated the Proto-Zambezi River system), have a recorded geological history spanning approximately 280 million years. Its original headwaters were formed when the End-Neoproterozoic to Ordovician amalgamation of the Gondwana Supercontinent created a central Himalayan-scale mountain belt, now called the Trans-Gondwana Mountain Range (at the core of the East Africa-Antarctica-Orogenic Belt). Eroded remnants of these mountains were the source of west-directed Dwyka glacial sediments and Ecca and Upper Karoo, Permo-Triassic, rift-controlled lakes and rivers across West Gondwana. The reversed drainage of the Zambezi River started to flow eastwards through the same rift valleys in the Middle Jurassic (at about 165 Ma), as Africa started to separate from the eastern part of West Gondwana, with the resultant development of an eastern seaboard. This second stage in the evolution of the Zambezi River mirrored sequential openings of the Indian and Atlantic Oceans, in the post-Gondwana interplay between epeirogeny and rifting. Protracted longevity of the Zambezi River and its ancient precursor shows that major drainage systems can survive plate break-up, albeit with changed flow directions and continuously evolving catchments.

Data from 23 wells were used to quantify the sedimentary budgets in the Tanzania coastal basin in order to unravel the uplift chronology of the sourcing area located in the East African Rift System. We quantified the siliciclastic sedimentary volumes preserved in the Tanzania coastal basin corrected for compaction and in situ (e.g., carbonates) production. We found that the drainage areas, which supplied sediments to this basin, were eroded in four episodes: (1) during the middle Jurassic, (2) during the Campanian–Palaeocene, (3) during the middle Eocene and (4) during the Miocene. Three of these high erosion and sedimentation periods are more likely related to uplift events in the East African Rift System and earlier rift shoulders and plume uplifts. Indeed, rapid cooling in the rift system and high denudation rates in the sediment source area are coeval with these recorded pulses. However, the middle Eocene pulse was synchronous with a fall in the sea level, a climatic change and slow cooling of the rift flanks and thus seems more likely due to climatic and eustatic variations. We show that the rift shoulders of the East African rift system have inherited their present relief from at least three epeirogenic uplift pulses of middle Jurassic, Campanian–Palaeocene, and Miocene ages.

In this study, data from 41 wells were used to quantify the evolution of the sedimentary budget in the Southern Mozambique passive margin basin, with a high temporal resolution for the Cenozoic period. We found that the drainage areas, which supplied sediments to the Southern Mozambique Basin, were eroded in two episodes. The first, of Mid–Late Cretaceous in age, is concordant with both thermochronological datation and sedimentary fluxes estimated by other studies in the Namibian and South African and Northern Mozambique margins. This erosion episode ended when the African surface, as defined by Burke and Gunnel (2008), had become flat and low-lying over most of the South African Plateau by ∼65 Ma. Carbonate sediment deposition became more important in the shallow waters of the Mozambique basin after that time. The second erosion episode began at ∼23 Ma and is likely due to an uplift event of the North-eastern part of the South African Plateau. It seems that the Limpopo catchment and the whole area sourcing the studied basin have inherited their present relief from two epeirogenic uplift pulses of Late Cretaceous and Miocene ages.

We combine 15 new 40 Ar/ 39 Ar ages with existing age constraints of basalts to investigate the incision and denudation history of the ∼150-km-long Rio San Jose (RSJ) of west-central New Mexico (USA) over the past 4 Ma. Temporal and spatial scales of differential incision may help evaluate the relative importance of neotectonic, geomorphic and climatic forcings. The RSJ is a southeast-flowing river that orthogonally crosses the northeast-trending Jemez volcanic lineament, which is underlain by a zone of low-velocity mantle. Preserved basalt flows along the length of the river at different elevations that directly overlie river gravels are used to construct paleoprofiles of the RSJ and give insight into the differential incision history, which can test the hypothesis that epeirogenic uplift associated with the Jemez lineament influenced differential incision of the RSJ. Observations include (1) a northeast-trending graben along the central reach of the RSJ (El Malpais valley graben) which is parallel to the Jemez lineament, (2) the present-day east tilt of the originally west-flowing 3.7 Ma Mesa Lucero flow along the eastern edge of the Jemez lineament, and (3) modern profile convexities that are colocated with ca. 3 Ma paleoprofile convexities and are centered above the Jemez lineament. The arched ca. 3 Ma paleoprofile defined by the pre–Mount Taylor strath has greater convexity than younger profiles, suggesting neotectonic bowing of ∼135 m (∼50 m/Ma) in this reach over the past ∼3 Ma relative to areas off axis of the Jemez lineament, in spite of graben subsidence and aggradational fill in this reach exceeding 100 m. Differential incision of the 184 ka Suwanee flow at the edge of the Colorado Plateau may be attributable to base-level fall in downstream reaches of the RSJ and/or headwater uplift, and more erosive climate in the past several hundred thousand years. However, these observations, when considered together, cannot be explained entirely by geomorphic or climatic forcings. Rather, they are best interpreted as resulting from surface uplift centered over the northeast-trending Jemez lineament, and our model suggests that both the faulting and broad bending may relate to mantle driven epeirogeny that caused differential river incision. Several interacting neotectonic and magmatic mechanisms may have contributed to postulated uplift. Magmatically driven geodynamic uplift forcings may include construction of the Mount Taylor stratovolcano just north of the RSJ that changed surface elevation by several kilometers at the volcanic peak itself. However, semisteady denudation and similar incision rates in other rivers in the region indicate that a regional erosional landscape was the primary driver of differential river incision over the past 5–8 Ma. Our focus on the pre–Mount Tayler RSJ paleoprofile reinforces this conclusion. Other mantle-related uplift mechanisms that may have generated mantle buoyancy include thermal buoyancy or magmatic inflation due to dike and sill networks related to the building of the Mount Taylor stratovolcano and eruption of Zuni-Bandera volcanic fields. Both could have contributed to uplift, but their relative importance is unknown. Broad epeirogenic uplift is also possible due to small-scale upper mantle convection beneath a thin elastic plate and resulting dynamic topography.

The central and southern Perth Basin in southwestern Australia has a geological history involving multiple regional unconformity-forming events from the Permian to Recent. This study uses sonic transit time analysis to quantify the magnitudes of net and gross exhumation for four stratigraphic periods from 43 wells. Most importantly, we quantify gross exhumation of the Permian–Triassic, Triassic–Jurassic, Valanginian break-up and post-Early Cretaceous events. Post-Early Cretaceous gross exhumation averages 900-m offshore and 600-m onshore. Up to 200 m of this exhumation may be attributed to localized fault block rotation during extension in the Late Cretaceous and/or reverse fault re-activation due to the compressive stresses in Australia in the last 50 Ma. The remainder is attributed to regional exhumation caused by epeirogenic processes either during the Cenozoic or at the Aptian–Albian boundary. Maximum burial depths prior to the Valanginian unconformity-forming event were less than those reached subsequently, so that the magnitude of Valanginian break-up exhumation cannot be accurately quantified. Gross exhumation prior to the break-up of Gondwana was defined by large magnitude differences (up to 2500 m) between adjoining sub-basins. At the end of Triassic, exhumation is primarily attributed to reverse re-activation of faults that were driven by short-wavelength inversion and exhumation at the end Permian is likely caused by uplift of rotated fault blocks during extension. The evidence from quantitative exhumation analysis indicates a switch in regime, from locally heterogeneous before break-up to more regionally homogeneous after break-up.

The sedimentary fill of the Parnaíba basin in NE Brazil is punctuated by two episodes of basaltic magmatism in Jurassic and Cretaceous times, known as the Mosquito and Sardinha formations, respectively. A quantitative understanding of the depth and degree of melting that generated these basalts should provide useful constraints on the history of vertical motions in this cratonic basin. We carried out forward and inverse modelling of major, trace and rare earth element concentrations for primitive melts from both igneous provinces. We calculated the melt fraction as a function of depth to determine the melt volumes and mantle potential temperatures. Our results suggest that both episodes of magmatism resulted from shallow decompression melting within the asthenospheric mantle. The Mosquito basalts record an excess temperature of 55–75°C and are probably related to the widespread Central Atlantic Magmatic Province associated with the initial break-up of Gondwanaland. By contrast, the Sardinha basalts record localized lithospheric thinning to less than half its original thickness with excess temperatures of 15–25°C. This younger activity is probably part of the Paraná–Etendeka large igneous province, which is linked to rifting between South America and Africa. We suspect that these magmatic episodes are associated with phases of regional epeirogenic uplift affecting the Parnaíba basin.

The Coorong Coastal Plain is a distinct morphotectonic province in southern Australia covering an area of approximately 34,600 km2. The coastal plain preserves a long Quaternary record of temperate carbonate sedimentation in the form of high wave energy barrier shoreline successions and associated back-barrier facies formed in low energy, estuarine-lagoon environments. The barriers occur sub-parallel to the modern coastline and to each other due to ongoing epeirogenic uplift. The coastal barriers (locally termed Dune Ranges), the principal focus of this book, formed during successive sea level highstands over the past 1 Ma and generally increase in age landwards. Some barriers, however, are composite structures having formed in more than one interglacial or interstadial. An older succession of Pliocene to possibly Early Pleistocene coastal barriers occur farther inland as part of the later stage progradational sequence of the Murray Basin and have been mapped as Loxton-Parilla Sands. The preservation of successive Quaternary shoreline features has resulted from slow epeirogenic uplift, calcareous cementation of dune limestone (aeolianite), and regional calcrete development. Across the coastal plain from Robe to Naracoorte, the mean uplift rate is approximately 70 mm/ka. In the region surrounding the Holocene and Pleistocene volcanic centres in the southern-most portion of the coastal plain, a higher rate of uplift of 130 mm/ka has been determined.

Cratonic depositional systems in the Central Montana Trough involve the Devonian--Carboniferous boundary (DCB), and reflect both subtle regional epeirogeny and significant global glacioeustatic controls. A palynologic analysis of the upper Three Forks, Sappington and lower Lodgepole formations was carried out at the classic Logan Gulch location in Horseshoe Hills. The lower Trident Member of Three Forks Formation yielded low-diversity cosmopolitan, long ranging phytoplankton and few spores species (LAs1), attributed to the middle Famennian. The upper part of the same green seaway shale yielded only leiosphaerids and Botryococcus (LAs2), along with an external mold of a clymenid ammonoid. Age-diagnostic spores Retispora lepidophyta, Verrucosisporites nitidus and Vallatisporites vallatus from middle Sappington siltstone (LAs3) indicated a Strunian LN Zone. Two more assemblages from upper Cottonwood Canyon Member (LAs4) and false Bakken (LAs5), in the lower Lodgepole Formation yielded scarce, poorly preserved spores. The presence of Waltzispora polita in LAs4 indicated a Tournaisan-Visean age. Fil: Di Pasquo Lartigue, Maria. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; Argentina Fil: Grader, George W.. PRISEM Geoconsulting; Estados Unidos Fil: Warren, Audrey. University of Nevada; Estados Unidos Fil: Rice, Beverly. University of Nevada; Estados Unidos Fil: Isaacson, Peter. University of Idaho; Estados Unidos Fil: Doughty, P. Ted. PRISEM Geoconsulting; Estados Unidos