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This paper contributes to an understanding of the tectono‐sedimentary evolution of the South Pyrenean foreland system by reviewing the chronostratigraphic framework of the basin infill in its eastern sector. Six sections are analysed and cross‐correlated to build a 6.5 km thick composite magnetostratigraphy that represents the complete record of the Cadí Nappe in the Ripoll Syncline. New and previous magnetostratigraphic sections are integrated with available biostratigraphy to provide a new age calibration of the sedimentary succession of the Cadí Nappe, encompassing from Palaeocene to Middle Lutetian age. The proposed correlation with the Geomagnetic Polarity Time Scale aims at best reconcile magnetostratigraphic data with the regional biochronology built on the marine Shallow Benthic Zonation (SBZ biozones), the continental mammalian biochronology (MP levels) and the newly collected charophyte data. A subsidence analysis was performed on the calibrated composite succession, resulting in two well‐defined intervals bounded by a hiatus. A Palaeocene to Early Eocene interval with low (11–21 cm/kyr) total subsidence rates, and an Early to Middle Eocene interval, characterised by high (70–75 cm/kyr) total subsidence rates. The detailed trends in both subsidence and sedimentation mark the development and evolution of the foreland depozones, from distal foreland depozones to foredeep and wedge‐top depozones, relative to the emplacement of the Pedraforca Nappe and Cadí Thrust Nappe. The most pronounced sedimentary shift in the Cadí Nappe occurred at 49 Ma, with the rapid drowning of the carbonate platforms and its transition into talus and deep basinal environments. Carbonate platforms collapsed and resedimented on the talus of the elongated trough, newly formed parallel to the orogenic front. This marked the onset of tectonic subsidence triggered by the submarine emplacement of the Lower Pedraforca Nappe. The emersion of the orogenic wedge drove the entry of siliciclastics, lagged by 1 Myr, into the Ripoll Trough. The foredeep filled rapidly (5.5 km thickness in less than 7 Myr) compared to other South Pyrenean regions, favoured by its semi‐enclosed palaeogeography. The emplacement of the Vallfogona Thrust as early as the Middle Lutetian (43 Ma) brought the Cadi Nappe into a wedge‐top setting. However, the Ripoll growth syncline continued acting as a temporary sink for alluvial sedimentation while a foredeep developed further south in the autochthonous Ebro Basin. The flexural response of the Iberian plate to the tectonic thickening of the Axial Zone counterbalanced for a period the local uplift of the Cadi Nappe, providing accommodation space for the top sediments filling the Ripoll Syncline. [ABSTRACT FROM AUTHOR]

The fates of terrestrial organic carbon (OCterr) during fluvial transport from land to ocean are still not well constrained. This study systematically examines the evolution and dynamics of OCterr along the river‐estuary‐coastal ocean continuum in three fluvial systems discharging to the Chinese marginal seas. The 14C‐depleted characteristics of bulk OC and molecular components of riverine suspended sediments and marine sediments suggest that the Chinese marginal seas are a significant sink of pre‐aged OCterr. Our study reveals significant apparent aging of OCterr within estuaries, likely due to degradation of (younger) labile components, and apparent rejuvenation of OCterr in shelf systems, likely reflecting inputs of younger OCterr from proximal sources along the sediment dispersal pathway. The aging and rejuvenation of OCterr along the river‐ocean continuum confounds the use of plant wax lipid 14C to constrain lateral transport times, and sheds light on more complex OCterr dynamics in marginal seas. Plain Language Summary: Determining the factors driving degradation of terrestrial organic carbon (OCterr) is important for understanding the fate of OCterr in marginal seas and its impact on the global carbon cycle. In this study, we use bulk and molecular‐level carbon isotopic measurements as well as sedimentological data to investigate how OCterr characteristics evolve along the river‐estuary‐coastal ocean continuum for three different river systems discharging into the Chinese marginal seas. Marked decreases in the OCterr abundance and 14C contents reveal marked aging associated with degradation processes within estuaries over relatively short transport distances, likely due to degradation of younger and labile OCterr. Both aging and apparent "rejuvenation" of OCterr after estuarine transport was observed in different shelf systems, the latter likely resulting from inputs of fresh OCterr from proximal sources. Our findings suggest both sources and transport processes influence terrestrial OC and biomarker signatures in marginal sea sediments, highlighting the complexity of OCterr dynamics in coastal systems. Key Points: Bulk and molecular 14C values suggest millennial‐aged terrestrial OC transport along the Chinese river‐estuary‐coastal ocean continuumRapid degradation and significant aging of terrestrial OC co‐occur during estuarine processingApparent aging and rejuvenation of terrestrial OC along‐shelf transport confounded the transport time estimated by plant wax lipid 14C [ABSTRACT FROM AUTHOR]

The interplay of rapid climate change and tectonics drives landscape development, sediment routing, and deposition in early‐stage continental rift systems. The Lake Malawi Rift, in the Western Branch of the East African Rift, is an archetype of a juvenile rift and an ideal natural laboratory for evaluating lacustrine source‐to‐sink systems on orbital or shorter timescales. We examine the interplay of these processes over the past 140 kyr using observations from nested seismic reflection data sets tied to scientific drill cores, which calibrate numerical forward models of this closed sedimentary system. Fault slip rates measured from seismic data drive tectonic displacements in the model. Satellite‐derived precipitation maps constrain modern precipitation and are scaled to previous hydrologic balance studies to reconstruct past climates. Our model reproduces known sediment thicknesses across the rift and accounts for 96% of the estimated siliciclastic sediment deposited over the past 140 kyr. The results demonstrate that the onset of arid climate conditions (140–95 kyr BP) causes extreme drainage adjustments downstream and the formation of mega‐catchments that flow axially into a shallow restricted paleo‐lake. Sedimentation rates during this time are twice the present values due to increased sediment focusing via these axial systems into a much smaller, hydrologically closed lake. As the climate became wetter (95–50 kyr BP), the lake rapidly expanded, decreasing both erosion and sedimentation rates across the rift. This closed‐loop approach allows us to evaluate the role of high‐frequency climate change in modulating basin physiography as well as sediment fluxes in juvenile rift systems. Plain Language Summary: During the earliest stages of continent formation, the movement and deposition of sediment across the changing landscape is driven by the interplay of rapid changes in climate, as well as vertical motions in the Earth surface caused by earthquakes. The deep lakes of eastern Africa, and their catchments are ideal locations to study the interactions between climate and the motions on the Earth surface because they are not deeply buried, deformed, or covered by vast ocean basins. We focus on the evolution of Lake Malawi in response to the interaction of these processes over the past 140 kyr using sub‐surface acoustic images tied to sedimentary records, which help constrain a mathematical model of landscape change. Our model reproduces 96% of the known volume of sediment over the past 140 kyr. The fast onset of a dry climate causes extreme adjustments of rivers into two large systems that flow into a small lake, ∼50 m deep. Wetter conditions cause a rapid expansion and deepening of the lake, causing these larger rivers to split into smaller ones. These results help constrain the early continental margin formation compared to older systems that may be deformed or deeply buried. Key Points: Using a closed‐loop forward modeling approach, we assess the landscape evolution of the Lake Malawi Rift over the past 140 kyrHigh‐frequency fluctuations in climate cause rapid base‐level changes and major drainage adjustments that focus sedimentSediment focusing is twice as high during arid periods and has the potential to prolong fault lifespan [ABSTRACT FROM AUTHOR]

The duration and extent of sediment routing systems are intrinsically linked to crustal‐ to mantle‐scale processes. Therefore, distinct changes in the geodynamic regime may be captured in the detrital record. This study attempts to reconstruct the sediment routing system of the Canning Basin (Western Australia) during the Early Cretaceous to decipher its depositional response to Mesozoic‐Cenozoic supercontinent dispersal. Specifically, we reconstruct source‐to‐sink relationships for the Broome Sandstone (Dampier Peninsula) and proximal modern sediments through multi‐proxy analysis of detrital zircon (U–Pb, Lu–Hf and trace elements) and detrital rutile (U–Pb and trace elements). Multi‐proxy comparison of detrital signatures and potential sources reveals that the majority of the detrital zircon and rutile grains are ultimately sourced from crystalline basement in central Australia (Musgrave Province and Arunta region) and that proximal sediment supply (i.e., Kimberley region) is negligible. However, a significant proportion of detritus might be derived from intermediate sedimentary sources in central Australia (e.g., Amadeus Basin) rather than directly from erosion of crystalline basement. Broome Sandstone data are consistent with a large‐scale drainage system with headwaters in central Australia. Contextualization with other broadly coeval drainage systems suggests that central Australia acted as a major drainage divide during the Early Cretaceous. Importantly, reorganization after supercontinent dispersal is characterized by the continuation of a sediment pathway remnant of an earlier transcontinental routing system originating in Antarctica that provided a template for Early Cretaceous drainage. Review of older Canning Basin strata implies a prolonged denudation history of central Australian lithologies. These observations are consistent with the long‐lived intracontinental tectonic activity of central Australia governing punctuated sediment generation and dispersion more broadly across Australia and emphasize the impact of deep Earth processes on sediment routing systems. [ABSTRACT FROM AUTHOR]

Summary: We present a study to estimate the large‐scale landscape history of a continental margin, by establishing a source‐to‐sink volume balance between the eroding onshore areas and the offshore basins. Assuming erosion as the primary process for sediment production, we strive to constrain a numerical model of landscape evolution that balances the volumes of eroded materials from the continent and that deposited in the corresponding basins, with a ratio imposed for loss of erosion products. We use this approach to investigate the landscape history of Madagascar since the Late Cretaceous. The uplift history prescribed in the model is inferred from elevations of planation surfaces formed at various ages. By fitting the volumes of terrigenous sediments in the Morondava Basin along the west coast and the current elevation of the island, the landscape evolution model is optimized by constraining the erosion law parameters and ratios of sediment loss. The results include a best‐fit landscape evolution model, which features two major periods of uplift and erosion during the Late Cretaceous and the middle to late Cenozoic. The model supports suggestions from previous studies that most of the high topography of the island was constructed since the middle to late Miocene, and on the central plateau the erosion has not reached an equilibrium with the high uplift rates in the late Cenozoic. Our models also indicate that over the geological time scale a significant portion of materials eroded from Madagascar was not archived in the offshore basin, possibly consumed by chemical weathering, the intensity of which might have varied with climate. [ABSTRACT FROM AUTHOR]

Sedimentary rocks provide key information on source‐to‐sink systems and the regional expression of plate tectonics. The abruptly changing provenance signature of sedimentary rocks is commonly ascribed to changes in the source regions, such as continental collision events, the rise of mountain chains, reorganization of river systems and climatic change. However, moving the positions of the sinks (depocenters) geographically can also change the provenance record, but this is rarely considered. Typically, large‐scale strike‐slip faults can transport depocenters for long distances, thus altering the provenance information. In this study, we present a systematic investigation of the provenance changes in the Sikhote‐Alin orogenic belt in the Russian Far East to evaluate this process. The Central Sikhote‐Alin Fault is a margin‐parallel strike‐slip fault that developed along the NE Asian continental margin from the late Mesozoic. Our new detrital zircon U‐Pb data, together with a compilation of geochronological data, indicate two different types of provenance signatures available: the sediments to the west of the fault were mainly derived from the adjacent Central Asian Orogenic Belt, but to the east of the fault, they were mainly supplied from the Korean Peninsula, which is several hundred kilometers away. It is proposed that these different sedimentary rocks were juxtaposed by syn‐ and post‐subduction sinistral displacements along the fault, and were not related to local variations in the source regions. Thus, understanding the shifting positions of depocenters is important when decoding provenance change because lateral displacement is critical for reconstructing regional paleogeography along oblique convergent plate margins. Plain Language Summary: Drainage systems on Earth's continents carry abundant sediments from their sources to sinks. These sediments, which record climatic, topographic, tectonic and river dynamic information during their journeys, are finally preserved as sedimentary rocks. By studying them, geologists can decode the ancient source‐to‐sink systems. Events occurring in the source regions are always emphasized to explain the varying information in the sediments. For example, the rise of mountains can migrate river's watershed and drainage basins, changing the characteristics of materials. Sometimes, however, simply moving positions of the sinks/basins also can achieve similar effects, such as basins moved by large strike‐slip faults. Here, our research in Sikhote‐Alin, Russian Far East shows that the sediments have two age spectrum patterns, indicating two provenance types along the NE Asian margin during the late Mesozoic. We suggest that the two types were juxtaposed by a large‐scale strike‐slip fault during and/or after their deposition. The different provenance features in Sikhote‐Alin was caused by the large‐scale margin‐parallel motion, instead of any variations in the sources. Similar tales were reported in NW America, northeastern Tibetan Plateau and other regions globally. Thus, understanding the shifting positions of sinks/basins is important when interpreting provenance change and reconstructing regional paleogeography. Key Points: Provenance change along the NE Asian margin was caused by large strike‐slip faults cutting depocenters, not variations in the sourcesMoving geographic positions of depocenters is rarely considered, but need more attentions when analyzing provenance changeLinking large strike‐slip faults and sedimentary records can importantly contribute to plate and geographic reconstructions [ABSTRACT FROM AUTHOR]

Pleistocene glaciations have promoted important landscape transformations as a result of high rates of erosion and rapid sediment evacuation to adjacent marine basins. In the Patagonian Andes the role of the Patagonian Ice Sheet on landscape evolution, in particular the spatial patterns of glacial erosion and its influence on sediment fluxes, is poorly documented. Here, we investigate the Middle and Late Pleistocene sedimentary record of the continental slope from Ocean Drilling Program (ODP) Site 861, offshore Patagonia (46°S), to evaluate the link between glaciations, mountain range erosion and continental margin strata formation. Petrographic analysis of the sand‐size fraction (0.063–2 mm) and ɛNd and 87Sr/86Sr measurements in the silt‐size fraction (10–63 µm) indicate that glacial erosion over the last 350,000 years has focused within the Patagonian Batholith, with a minor influence of a proximal source to the drilling site, the Chonos Metamorphic Complex. This shows that erosion has focused in the core of the northern Patagonian Andes, coinciding roughly with the location of the Liquiñe‐Ofqui Fault Zone and the zone of concentrated precipitation during glaciations, suggesting a combined climatic and structural control on glacial erosion. Temporal variation in the provenance signal is contemporaneous with a marked change in the stratigraphy of ODP Site 861 that occurred after the glaciation of MIS 8 (~240 kyr ago). Before MIS 8, a restricted provenance signal and coarse lithofacies accumulated on the continental slope indicates spatially restricted erosion and efficient transfer of sediment towards the ocean. In contrast, very high provenance variability and finer continental slope lithofacies accumulation after MIS 8 suggest a disorganized expansion of the areas under erosion and a more distal influence of ice sediment discharge to this site. We argue that this change may have been related to a re‐organization of the drainage patterns of the Patagonian Ice Sheet and flow of outlet glaciers to the continental margin during the last two glaciations. [ABSTRACT FROM AUTHOR]

This study constrains the sediment provenance for the Late Cretaceous–Eocene strata of the Ager Basin, Spain, and reconstructs the interplay between foreland basin subsidence and sediment routing within the south‐central Pyrenean foreland basin during the early phases of crustal shortening using detrital zircon (DZ) U‐Pb‐He double dating. Here we present and interpret 837 new DZ U‐Pb ages, 113 of which are new DZ (U‐Th)/He double‐dated zircons. U‐Pb‐He double dating results allow for a clear differentiation between different foreland and hinterland sources of Variscan zircons (280–350 Ma) by leveraging the contrasting thermal histories of the Ebro Massif and Pyrenean orogen, recorded by the zircon (U‐Th)/He (ZHe) ages, despite their indistinguishable U‐Pb age signatures. Cretaceous–Paleocene sedimentary rocks, dominated by Variscan DZ U‐Pb age components with Permian–Triassic (200–300 Ma) ZHe cooling ages, were sourced from the Ebro Massif south of the Ager Basin. A provenance shift occurred at the base of the Early Eocene Baronia Formation (ca. 53 Ma) to an eastern Pyrenean source (north‐east of the Ager Basin) as evidenced by an abrupt change in paleocurrents, a change in DZ U‐Pb signatures to age distributions dominated by Cambro‐Silurian (420–520 Ma), Cadomian (520–700 Ma), and Proterozoic–Archean (>700 Ma) age components, and the prominent emergence of Cretaceous–Paleogene (<90 Ma) ZHe cooling ages. The Eocene Corçà Formation (ca. 50 Ma), characterized by the arrival of fully reset ZHe ages with very short lag times, signals the accumulation of sediment derived from the rapidly exhuming Pyrenean thrust sheets. While ZHe ages from the Corçà Formation are fully reset, zircon fission track (ZFT) ages preserve older inherited cooling ages, bracketing the exhumation level within the thrust sheets to ca. 6–8 km in the Early Eocene. These DZ ZHe ages yield exhumation rate estimates of ca. 0.03 km/Myr during the Late Cretaceous–Paleocene for the Ebro Massif and ca. 0.2–0.4 km/Myr during the Eocene for the eastern Pyrenees. [ABSTRACT FROM AUTHOR]

Lower Palaeozoic fluvial systems tend to be more sand‐prone than those of later eras and the nature of coastal environments less certain. Field studies are presented that characterize the fluvial to marine transition over a distance of 80 km, in the Lower Cambrian of the Cotentin Peninsula, northern France. The sedimentary rocks are divided into six facies associations which represent deposition in proximal fluvial, distal fluvial, delta plain, delta front, pro‐delta and offshore carbonate bank environments. The basin fill is sandstone‐dominated and subdivided into three stratigraphic intervals. A 200 to 300 m thick basal interval contains very coarse‐grained fluvial sandstones deposited during a relative sea level lowstand. An overlying interval, 250 to 1500 m thick, is a facies mosaic. Fluvial strata in the north‐west pass laterally south‐east into deltaic and shallow marine pro‐delta sediments. The delta front deposits show repetitively stacked, upward‐coarsening parasequences, 8 to 10 m thick, which reflect the repeated progradation of lobate, fluvially‐dominated deltas onto a shallow marine shelf. The deltas formed following marine transgression and accumulated during a period of gradually rising relative sea level. An upper unit, 130 m thick, containing offshore stromatolitic and oolitic limestones, caps the study interval and represents deposition during a relative sea level highstand. The fluvial and delta distributary channel sandstones of the middle unit contain <1% mudstone. The cohesionless substrate determined that deltaic distributaries were predominantly braided in character and subject to common bifurcations which resulted in an ordered diminution of channel size and competence in a seaward direction. Terminal distributary channels show evidence of migratory levées and mouth‐bars and consistently delivered fine to medium‐grained sand to the delta front. The study highlights an example of pre‐vegetation deltaic sedimentation that was hydraulically organized and predictable, despite being fed by braided fluvial systems with high levels of peak discharge. [ABSTRACT FROM AUTHOR]

Dynamic topography due to mantle flow contributes to shaping Earth's evolving landscapes by affecting sediment routing, which has rarely been explored in source‐to‐sink contexts. Here we design a generic model to investigate the impact of dynamic topography on both landscape evolution and stratigraphic formations. An imposed wave of dynamic topography propagates laterally under a fixed continent, exerting transient surface uplift and subsidence. We find that a migrating dynamic topography can induce significant drainage reorganizations and affect sediment routing from source to sink. Variations in sediment supply driven by the lateral migrating dynamic topography contribute to the formation of diachronous unconformities along the margin. The predicted sediment flux histories are then put into perspective with the Cretaceous sedimentary records along the Southern African margins. Finally, we demonstrate that correlating offshore depositional hiatuses and unconformities has the potential to constrain the spatiotemporal evolution of past dynamic topography events. Plain Language Summary: Convective motion within Earth's interior result in transient uplift and subsidence of the surface is called dynamic topography. This process slowly shapes landscapes over millions of years and identifying its fingerprints in the rock record remains a challenge. This study uses numerical modeling to investigate the erosional and depositional response of landscapes to sea level change and to mantle flow. We show that unlike sea level change, dynamic topography reorganizes river flows and changes sediment supply to offshore regions, generating various stratal patterns. We model a simple circular landscape that evolves similarly to the southern African landscape between 140 and 66 million years ago and suggest sedimentary fingerprints to link the evolution of the Earth's surface to the dynamics of its deep interior. Key Points: A propagating wave of dynamic topography can induce significant drainage reorganizations and affect sediment routing from source to sinkVariations in sediment supply driven by the migration of dynamic topography can create diachronous unconformities along continental marginsOur model predicts sediment flux histories comparable to that along the Southern African margins during Cretaceous times [ABSTRACT FROM AUTHOR]

The sedimentary archive preserved at passive margins provides important clues about the evolution of continental topography. For example, histories of African uplift, erosion, and deposition of clastic sedimentary rock provide information about mantle convection. Furthermore, relating histories of uplift and erosion from regions where sediment is generated to measurements of efflux is important for understanding basin evolution and the distribution of natural resources. We focus on constraining Mesozoic to Recent solid sedimentary flux to northwest Africa's passive margin, which today is fed by rivers draining dynamically supported topography. Histories of sedimentary flux are calculated by mapping stratigraphy using seismic reflection and well data courtesy of Tullow Oil Plc and TGS. Stratigraphic ages, conversion from two‐way time to depth and compaction, are parameterized using biostratigraphic and check‐shot records from exploration, International Ocean Discovery Program and Deep Sea Drilling Project wells. Results indicate that Late Cretaceous to Oligocene (∼100–23 Ma) sedimentary flux decreased gradually. A slight increase in Neogene sedimentary flux is observed, which is concomitant with a change from carbonate to clastic sedimentation. Pliocene to Recent (∼5–0 Ma) flux increased by an order of magnitude. This history of sedimentary flux and facies change is similar to histories observed at other African deltas. To constrain sources of sedimentary flux, 14,700 longitudinal river profiles were inverted to calculate a history of continental uplift. These results were used to parameterize a simple "source‐to‐sink" model of fluvial erosion and sedimentary efflux. Results suggest that increased clastic flux to Africa's deltas from ∼30 Ma was driven by denudation induced by dynamic support. Key Points: Mesozoic to Recent solid sedimentary flux from West African seismic and well dataPredict sedimentary flux histories from inversion of 14,700 African river profilesNeogene uplift of dynamically supported swells generated punctuated sedimentary flux [ABSTRACT FROM AUTHOR]

We investigate the late Miocene‐Pleistocene offshore sedimentary record of the Yakutat microplate to evaluate the spatial and temporal variations in rock exhumation and sediment routing patterns at the heavily glaciated and actively converging plate boundary in southeast Alaska. We present 1,456 new fission track ages and 1,372 new U‐Pb ages from double‐dated detrital zircons derived from fourteen samples collected from offshore. We integrate our results with published geochronology and thermochronology data onland and offshore in order to constrain grain provenance. We find that offshore strata deposited east of the fold and thrust belt are sourced from the rapidly exhuming areas along the entire Fairweather Fault, the northeastern part of the syntaxial region, as well as the slowly exhuming Insular superterrane. In contrast, the western strata are sourced from the emerging fold and thrust belt and the Chugach Metamorphic Complex located north of the plate boundary. In these samples we identified a change in sediment provenance, which we suggest marks the capture of the Bagley Ice Valley by the proto‐Bering Glacier at the transition from the early to late Pliocene. This implies that the modern Bagley‐Bering Glacier System is much older than previously known. Strata deposited at ~8.6 Ma suggest that extreme rapid exhumation was already ongoing in the late Miocene, which supports previous findings in deep‐sea deposits. Overall, the data help discern several stages in the evolution of sediment routing patterns in response to dynamic tectonic and surficial processes along this active convergent margin. Plain Language Summary: Strong collisional tectonic processes and voracious glacial erosion shape the coastal region of southeast Alaska. This interplay between tectonics and climate‐driven surface processes resulted in the highest coastal mountain range—the St. Elias Mountains. In this study we investigate the sediment deposited in the adjacent Gulf of Alaska to reconstruct the changes in sediment source regions and erosion rates since the late Miocene through Pleistocene. We apply the U‐Pb and the fission track dating methods on hundreds of detrital grains to derive the time of crystallization and the time of cooling below 250°C on individual zircons. We find that the growing coastal mountains influenced the evolving glacial catchments. We identified a shift in sediment provenance between the early and late Pliocene time that we explain by the capture of the Bagley Ice field by the proto‐Bering Glacier. A change to more local sediment sources and limited lateral mixing occurred after the mid‐Pleistocene climate shift to longer glacial cycles and more intense glaciation. Key Points: We present new detrital zircon fission‐track and U‐Pb ages from late Miocene to Pleistocene strata of the Yakutat shelfShift in sediment source area at ~3.6±1 Ma suggests capture of the Bagley Ice Valley by the proto‐Bering GlacierStrata east of the fold and thrust belt was sourced by rapidly exhuming rocks along the Fairweather Fault [ABSTRACT FROM AUTHOR]

To better constrain the global carbon cycle fundamental knowledge of the role of carbon cycling on continental margins is crucial. Fjords are particularly important shelf areas for carbon burial due to relatively high sedimentation rates and high organic matter fluxes. As terrigenous organic matter is more resistant to remineralization than marine organic matter, a comprehensive knowledge of the carbon source is critical to better constrain the efficiency of organic carbon burial in fjord sediments. Here we investigated highly productive fjords in northern Norway and compare our results with both existing and new organic carbon to organic nitrogen ratios and carbon stable isotope compositions from fjords in mid‐Norway, west Svalbard, and east Greenland. The marine organic carbon contribution varies significantly between these fjords, and the contribution of marine organic carbon in Norwegian fjords is much larger than previously suggested for fjords in NW Europe and also globally. Additionally, northern Norwegian fjords show very high marine carbon burial rates (73.6 gC · m‐2 · year‐1) suggesting that these fjords are probably very distinct carbon burial hotspots. We argue that the North Atlantic Current inflow sustains these high burial rates and changes in the current strength due to ongoing climate change are likely to have a pronounced effect on carbon burial in North Atlantic fjords. Key Points: Organic matter sources in North Atlantic fjords are much more heterogeneous than previously estimatedOngoing climate change is likely to have a pronounced effect on carbon burial in North Atlantic fjords [ABSTRACT FROM AUTHOR]

Submarine volcanoes produce sediment that originates and remains in a deep‐water setting, never escaping the water column. This situation puts a twist on the idea of 'source to sink' pathways, where both source and sink are in the submarine realm. Submarine volcanoes may play a significant role in basin sedimentation and evolution, but direct observation of sediment production and dispersal from submerged volcanoes is logistically difficult. This study analyzes the Mohakatino Formation, a Miocene deep‐marine unit produced by ancient submarine volcanoes of the Taranaki Basin, New Zealand, to investigate sediment transport and deposition from these volcanoes. Outcrop analysis of the volcanogenic deposits suggests a submarine lobe environment in a north–south elongated sub‐basin, confined by the growing volcanic arc to the north and west and a fault‐controlled topographic high to the east. Composition and sedimentary structures indicate that most deposits in this area are reworked volcanogenic material, rather than primary deposits from individual eruption events, transported to the depocentre by eruption‐initiated and mass wasting‐initiated turbidity currents. This study highlights the need for submarine volcanoes to be considered in source to sink investigations, to ascertain their role as sediment sources to marine basins. Deeply submerged volcanoes are disconnected from some environmental signals, while sedimentation from shallow‐water volcanoes may be especially sensitive to perturbations in sea‐level and climate. In both cases, a short transfer zone between source and sink may increase the likelihood that source area signals are transmitted to the sedimentary record. [ABSTRACT FROM AUTHOR]

Models relating sediment supply to catchment properties are important in order to use the geological record to deduce landscape evolution and interplay between tectonics and climate. Water discharge (Qw) is an important factor in the widely used 'BQART' model, which relates sediment load to a set of measurable catchment parameters. Although many of the factors in this equation may be independently estimated with some degree of certainty in ancient systems, water discharge (Qw) certainly cannot. An analysis of a world database of modern catchments with 1255 entries shows that the commonly applied equation relating catchment area (A) to water discharge (Qw = 0·075A0·8) does not predict water discharge from catchment area well in many cases (R2 = 0·5 and an error spanning about three orders of magnitude). This is because the method does not incorporate the effect of arid and wet climate on river water discharge. The inclusion of climate data into such estimations is an opportunity to refine these estimates, because generalized estimates of palaeoclimate can often be deduced on the basis of sedimentological data such as palaeosol types, mineralogy and palaeohydraulics. This paper investigates how the relationship between catchment area and river discharge varies with four runoff categories (arid, semi-arid, humid and wet), which are recognizable in the geological record, and modifies the coefficient and exponent of the above-mentioned equation according to these classes. This modified model yields improved results in relating discharge to catchment area (R2 = 0·95 and error spanning one order of magnitude) when core, outcrop or regional palaeoclimate reconstruction data are available in nonarid systems. Arid systems have an inherently variable water discharge, and catchment area is less important as a control due to downstream losses. The model here is sufficient for many geological applications and makes it possible to include variations in catchment humidity in mass-flux estimates in ancient settings. [ABSTRACT FROM AUTHOR]

ABSTRACT The coupling relationships between hillslope and channel network are fundamental for the understanding of mountainous landscapes' evolution. Here, we applied dendrogeomorphic methods to identify the hillslope-channel relationship and the sediment transfer dynamics within an alpine catchment, at the highest possible resolution. The Schimbrig catchment is located in the central Swiss Alps and can be divided into two distinct geomorphic sectors. To the east, the Schimbrig earth flow is the largest sediment source of the basin, while to the west, the Rossloch channel network is affected by numerous shallow landslides responsible for the supply of sediment from hillslopes to channels. To understand the connectivity between hillslopes and channels and between sources and sink, trees were sampled along the main Rossloch stream, on the Schimbrig earth flow and on the Rossloch depositional area. Geomorphic observations and dendrogeomophic results indicate different mechanisms of sediment production, transfer and deposition between upper and lower segments of the channel network. In the source areas (upper part of the Rossloch channel system), sediment is delivered to the channel network through slow movements of the ground, typical of earth flow, shallow landslides and soil creep. Contrariwise, in the depositional area (lower part of the channel network), the mechanisms of sediment transfer are mainly due to torrential activity, floods and debris flows. Tree analysis allowed the reconstruction of periods of high activity during the last century for the entire catchment. The collected dataset presents a very high temporal resolution but we encountered some limitations in establishing the source-to-sink connectivity at the catchment-wide scale. Despite these uncertainties, for decennial timescales the results suggest a direct coupling between hillslopes and neighbouring channels in the Rossloch channel network, and a de-coupling between sediment sources and sink farther downstream, with connections possible only during extraordinary events. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the evolution of the Nile deep-sea turbidite system during the last 200 kyr, over a series of glacial to interglacial cycles. Six individual deep-sea fans were identified from an extensive field data set. Each fan comprises a canyon, channel system and terminal lobes. Two of these fan systems were possibly active at the same time, at least during some periods. Large-scale slope failures destroyed channel segments and caused the formation of new submarine fan systems. These slope failures thus played an important role in the overall evolution of the turbidite system. During the last glacial maximum ( ca 25 to 14·8 ka) the central and eastern parts of the Nile deep-sea turbidite system were relatively inactive. This inactivity corresponds to a lowstand in sea-level, and a period of arid climate and relatively low sediment discharge from the Nile fluvial system. Rapid accumulation of fluvial flood-derived deposits occurred across the shallower part of the submarine delta during sea-level rise between ca 14·8 and 5 ka. The most recent deep-sea channel–lobe system was very active during this period of rising sea-level, which is also associated with a wetter continental climate and increased sediment and water discharge from the Nile. Increased sediment deposition in shallower water areas led to occasional large-scale slope failure. The Nile deep-sea turbidite system was largely inactive after ca 5 ka. This widespread inactivity is due to retreat of the coastline away from the continental shelf break, and to a more arid continental climate and reduced discharge of sediment from the Nile. The Nile deep-sea turbidite system may be more active during periods of rising and high sea-level associated with wetter climates, than during lowstands, and may rapidly become largely inactive during highstands in sea-level coupled with arid periods. These acute responses to climate change have produced sedimentary/stratigraphic features that diverge from traditional sequence models in their nature and timing. This large-scale sedimentary system responded to monsoon-driven climate change and sea-level change in a system-wide and contemporaneous manner. [ABSTRACT FROM AUTHOR]