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Despite their very low relief and erosion rates, non‐orogenic (i.e., cratonic) continental domains account for over 60% of the Earth's exposed lands. Therefore, they contribute significantly to the clastic sediments and solutes exported to the ocean and should be accounted for in global studies. Nonetheless, they have been much less studied than orogenic domains. In this study, we establish the source‐to‐sink sedimentary budget of the sub‐saharan West African cratonic domain and its Equatorial Atlantic rifted margin using published low‐temperature thermochronological data to estimate onshore denudation and regional geological cross‐sections to estimate offshore accumulation. We show that during and immediately following rifting (130‐94 Ma), the build‐up and subsequent erosion of rift‐related relief resulted in a transient, 100–200 km wide strip along the margin recording high denudation rates (>50 m/Myr), while the inland domain underwent steady and very low denudation (<10 m/Myr). Afterward, the whole onshore domain underwent very low and steady denudation. Thus, the changes in post‐rift accumulation rates documented along the rifted margin were caused by changes in the climate and/or drainage network. During the Late Cretaceous, we document a regional rise in accumulation rates caused by the enlargement of drainage areas feeding the basins by a hinterlandward migration of the continental divide. During the Paleogene, we document a general drop in accumulation rates in all the basins of the African Atlantic margins caused by the global greenhouse climate, which enhanced the development of lateritic weathering mantles, storing clastic sediments on the continent and favoring solute exports to the ocean. Plain Language Summary: Cratons, shields and continental platforms have low relief and erode very slowly. As a result, they are often neglected while investigating sediment routing systems at the surface of the Earth over geological times. In this study, we determine the source‐to‐sink sedimentary budget of the sub‐saharan part of West Africa and its equatorial Atlantic margin. To do this, we estimate the histories of (a) erosion on the continent and (b) accumulation in the offshore basins. We show that the sub‐saharan region of West Africa has experienced very little erosion since at least 200 Ma. The only exception was the temporary removal of relief caused by the rift that split Africa and South America. Following that rifting, variations in sediment accumulation in the basins were driven by changes in climate that modified the way the continent was being eroded or by modifications of the river courses carrying sediments to the ocean. Key Points: The sub‐saharan West Africa cratonic domain underwent only very low steady denudation rates (<10 km/Ma) since Equatorial Atlantic riftingEquatorial Atlantic rifting altered the cratonic denudation only transiently, in a narrow domain corresponding to rift‐related relief erosionPost‐rift accumulation rates in the rifted margin basins were thus controlled by global climate change and/or drainage reorganizations [ABSTRACT FROM AUTHOR]

Abstract Despite their very low relief and erosion rates, non‐orogenic (i.e., cratonic) continental domains account for over 60% of the Earth's exposed lands. Therefore, they contribute significantly to the clastic sediments and solutes exported to the ocean and should be accounted for in global studies. Nonetheless, they have been much less studied than orogenic domains. In this study, we establish the source‐to‐sink sedimentary budget of the sub‐saharan West African cratonic domain and its Equatorial Atlantic rifted margin using published low‐temperature thermochronological data to estimate onshore denudation and regional geological cross‐sections to estimate offshore accumulation. We show that during and immediately following rifting (130‐94 Ma), the build‐up and subsequent erosion of rift‐related relief resulted in a transient, 100–200 km wide strip along the margin recording high denudation rates (>50 m/Myr), while the inland domain underwent steady and very low denudation (

Sediment mass‐balance analysis provides key constraints on stratigraphic architecture and its controls. We use the data‐rich Middle Jurassic Brent Delta sediment routing system in the proto‐Viking Graben, Northern North Sea, to estimate sediment budgets and mass‐balance between source areas and depositional sinks. Published studies are synthesised to provide an age‐constrained sequence stratigraphic framework, consisting of four previously defined genetic sequences (J22, J24, J26, J32). Genetic sequence J32 (3.9 Myr) records transverse progradation of basin‐margin deltas, sourced from the Shetland Platform to the west and Norwegian Landmass to the east. Genetic sequences J24 (1.1 Myr) and J26 (0.9 Myr) record the rapid progradation and subsequent aggradation of the Brent Delta along the basin axis, sourced from the uplifted Mid‐North Sea High to the south, and the western and eastern source regions. Genetic sequence J32 (2.2 Myr) records the retreat of the Brent Delta. Sediment budgets for the four genetic sequences are estimated using palaeogeographical reconstructions, isopach maps, and sedimentological analysis of core and well‐log data. The estimated net‐depositional sediment budget for the mapped Brent Delta system is 2.0–2.8 Mt/year. Temporal variations in net‐depositional sediment budget were driven by changes in tectonic boundary conditions, such as the onset of uplift before the deposition of genetic sequence J24. Over the same time period, the Shetland Platform, Norwegian Landmass and Mid‐North Sea High source regions are estimated to have supplied 2.3–5.6, 5.0–14.1, and 2.8–9.4 Mt/year of sediment, respectively, using the BQART sediment load model and independent geometrical reconstruction of eroded volumes, which are constrained by isostatic uplift estimates based on the geochemistry of syn‐depositional volcanic rocks. The net‐depositional sediment budget in the sink is an order‐of‐magnitude smaller than the total sediment budget supplied by the source regions (13.9–23 Mt/year). This discrepancy suggests that along‐shore transport by wave‐generated currents into the coeval Faroe‐Shetland Basin and/or down‐dip transport by gravity flows into the coeval western Møre Basin played a key role in redistributing sediments away from the Brent Delta system. [ABSTRACT FROM AUTHOR]

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The Huanghe once had a sediment flux of >1,000 Mt/yr, but this has decreased by ∼90% as its river sediment routing systems have undergone dramatic changes influenced by human activities such as dam construction. However, the way in which the sediment geochemistry of the river has responded to the altered sediment routing processes is not well known. This study investigates the sediment source‐to‐sink routing regime of the Huanghe River using Nd isotope fingerprinting. Four major source terranes, namely the Songpan‐Ganzi (SG) Block, Ordos Desert (OD), Chinese Loess Plateau (CLP) and North China Craton (NCC) are recognized according to their distinct Nd isotopes. The gradual downstream decrease in εNd values in sediments of the upper Huanghe indicates a decreasing contribution of material from the SG Block and a corresponding increase contribution of local underlying basement rocks, which is inferred to be related to sediment capture by a cascade of hydroelectric dams. A gradual increase in εNd from Yinchuan to Tongguan suggests an increasing contribution from the CLP under intense erosion. Relatively low εNd in the downstream sediments suggest a contribution from proximal NCC basement, consistent with the shift from deposition to erosion in the lower channel in recent years. The marked heterogeneity in Nd isotopes in the Huanghe sediments corresponds well to sediment source‐to‐sink processes in response to increasing human impacts. In a setting of global rivers facing strong anthropogenic impacts, the ways in which altered sediment routing systems affect river sediment geochemistry deserve more research attention. Plain Language Summary: The sediment flux of the Huanghe River (Yellow River) once exceeded 1,000 Mt/yr, but has decreased by ∼90% over the past 60 years owing mainly to the nature and intensity of human activity, during which river sediment transport processes have also changed. Here, we present Nd isotopic data for sediments from the Huanghe mainstream to investigate sediment provenances and the river sediment routing system under anthropogenic influences. Nd isotopes of potential source terrane materials allow the sediment provenances to be discriminated. The construction of cascade hydroelectric engineering projects in the upper reaches might have caused a marked decrease in sediment contribution from the Songpan–Ganzi Block, as evidenced from the gradual downstream decrease in sediment εNd in the upper reaches. The gradual increase in εNd values from Yinchuan to Tongguan suggests an increasing sediment contribution from the China Loess Plateau by intense erosion. However, relatively low εNd values in the lower reaches suggest an increased contribution of proximal sediment derived from basement of the North China Craton, with a shift from depositional to erosional processes in the lower reaches. The heterogeneity in Nd isotopes in the river sediments reveals sediment routing processes under the impact of anthropogenic activities and interventions. Key Points: Trace elements and Sr‐Nd isotopes are used to ascertain sediment provenance for modern Huanghe River in ChinaFour major source terranes are recognized and discriminated based on their unique Nd isotopic compositionsThe heterogeneity of Nd isotopes in the river sediments reveals the sediment routing regime under anthropogenic activity [ABSTRACT FROM AUTHOR]

The propagation of the deformation front in foreland systems is typically accompanied by the incorporation of parts of the basin into wedge‐top piggy‐back basins, this process is likely producing considerable changes to sedimentation rates (SR). Here we investigate the spatial‐temporal evolution of SR for the Tremp–Jaca Basin in the Southern Pyrenees during its evolution from a wedge‐top, foreredeep, forebulge configuration to a wedge‐top stage. SR were controlled by a series of tectonic structures that influenced subsidence distribution and modified the sediment dispersal patterns. We compare the decompacted SR calculated from 12 magnetostratigraphic sections located throughout the Tremp–Jaca Basin represent the full range of depositional environment and times. While the derived long‐term SR range between 9.0 and 84.5 cm/kyr, compiled data at the scale of magnetozones (0.1–2.5 Myr) yield SR that range from 3.0 to 170 cm/kyr. From this analysis, three main types of depocenter are recognized: a regional depocenter in the foredeep depozone; depocenters related to both regional subsidence and salt tectonics in the wedge‐top depozone; and a depocenter related to clastic shelf building showing transgressive and regressive trends with graded and non‐graded episodes. From the evolution of SR we distinguish two stages. The Lutetian Stage (from 49.1–41.2 Ma) portrays a compartmentalized basin characterized by variable SR in dominantly underfilled accommodation areas. The markedly different advance of the deformation front between the Central and Western Pyrenees resulted in a complex distribution of the foreland depozones during this stage. The Bartonian–Priabonian Stage (41.2–36.9 Ma) represents the integration of the whole basin into the wedge‐top, showing a generalized reduction of SR in a mostly overfilled relatively uniform basin. The stacking of basement units in the hinterland during the whole period produced unusually high SR in the wedge‐top depozone. [ABSTRACT FROM AUTHOR]

The East African Rift System (EARS) exerted a major influence on river drainage basins and regional climate of east Africa during the Cenozoic. Recent studies have highlighted an offshore branch of the EARS in the western Indian Ocean, where the Kerimbas Graben and the Davie Ridge represent its sea floor expression. To date, a clear picture of the impact and timing of this EARS offshore branch on the continental margin of the western Indian Ocean, and associated sediment dispersal pathways, is still missing. This study presents new evidence for four giant canyons along the northern portion of the Davie Ridge offshore Tanzania. Seismic and multibeam bathymetric data highlight that the southernmost three canyons are now inactive, supra‐elevated relative to the adjacent sea floor of the Kerimbas Graben and disconnected from the modern slope systems offshore the Rovuma and Rufiji River deltas. Regional correlation of dated seismic horizons, integrated with well data and sediment samples, proves that the tectonic activity driving the uplift of the Davie Ridge in this area has started during the middle‐upper Miocene and is still ongoing, as suggested by the presence of fault escarpments at the sea floor and by the location and magnitude of recent earthquakes. Our findings contribute to placing the Kerimbas Graben and the Davie Ridge offshore Tanzania in the regional geodynamic context of the western Indian Ocean and show how the tectonics of the offshore branch of the EARS modified the physiography of the margin, re‐routing the deep‐water drainage network since the middle Miocene. Future studies are needed to understand the influence of changing sea floor topography on the western Indian Ocean circulation and to evaluate the potential of the EARS offshore tectonics in generating tsunamigenic events. [ABSTRACT FROM AUTHOR]

Environmental changes within erosional catchments of sediment routing systems are predicted to modulate sediment transfer dynamics. However, empirical and numerical models that predict such phenomena are difficult to test in natural systems over multi-millennial timescales. Tectonic boundary conditions and climate history in the Panamint Range, California, are relatively well-constrained by existing low-temperature thermochronology and regional multi-proxy paleoclimate studies, respectively. Catchment–fan systems present there minimize sediment storage and recycling, offering an excellent natural laboratory to test models of climate-sedimentary dynamics. We used stratigraphic characterization and cosmogenic radionuclides (CRNs; 26 Al and 10 Be) in the Pleasant Canyon complex (PCC), a linked catchment–fan system, to examine the effects of Pleistocene high-magnitude, high-frequency climate change on CRN-derived denudation rates and sediment flux in a high-relief, unglaciated catchment–fan system. Calculated 26 Al/ 10 Be burial ages from 13 samples collected in an ∼180 m thick outcropping stratigraphic succession range from ca. 1.55 ± 0.22 Ma in basal strata, to ca. 0.36 ± 0.18–0.52 ± 0.20 Ma within the uppermost part of the succession. The mean long-term CRN-derived paleodenudation rate, 36 ± 8 mm/kyr (1 σ ), is higher than the modern rate of 24 ± 0.6 mm/kyr from Pleasant Canyon, and paleodenudation rates during the middle Pleistocene display some high-frequency variability in the high end (up to 54 ± 10 mm/kyr). The highest CRN-derived denudation rates are associated with stratigraphic evidence for increased precipitation during glacial–pluvial events after the middle Pleistocene transition (post ca. 0.75 Ma), suggesting 100 kyr Milankovitch periodicity could drive the observed variability. We investigated the potential for non-equilibrium sedimentary processes, i.e. increased landslides or sediment storage/recycling, to influence apparent paleodenudation rates; end-member mixing models suggest that a mixture of >50% low-CRN-concentration sediment from landslides is required to produce the largest observed increase in paleodenudation rate. The overall pattern of CRN-derived burial ages, paleodenudation rates, and stratigraphic facies suggests Milankovitch timescale climate transitions drive variability in catchment denudation rates and sediment flux, or alternatively that climate transitions affect sedimentary process regimes that result in measurable variability of CRN concentrations in unglaciated catchment–fan systems. [ABSTRACT FROM AUTHOR]

Evaluating the role of tectonics and climate as possible triggering mechanisms of landscape reconfigurations is essential for paleoenvironmental and paleoclimatic reconstructions. In this study an exceptional receptive closed Quaternary system of Patagonia (the Gastre Basin) is described, and examined in order to analyze factors triggering base-level drops. Based on a geomorphological approach, which includes new tectonic geomorphology investigations combined with sedimentological and stratigraphic analysis, three large-scale geomorphological systems were identified, described and linked to two major lake-level highstands preserved in the basin. The results indicate magnitudes of base-level drops that are several orders of magnitude greater than present-day water-level fluctuations, suggesting a triggering mechanism not observed in recent times. Direct observations indicating the occurrence of Quaternary faults were not recorded in the region. In addition, morphometric analyses that included mountain front sinuosity, valley width-height ratio, and fan apex position dismiss tectonic fault activity in the Gastre Basin during the middle Pleistocene–Holocene. Therefore, we suggest here that upper Pleistocene climate changes may have been the main triggering mechanism of base-level falls in the Gastre Basin as it is observed in other closed basins of central Patagonia (i.e., Carri Laufquen Basin). [ABSTRACT FROM AUTHOR]

Quaternary climatic and eustatic cycles in mid-latitude regions have led to more extensive alpine glaciations and continental shelf progradation, respectively. However, the glacial influence on sediment fluxes to the ocean creating continental margin strata is poorly documented. This contribution analyzes the provenance of fine sediment accumulating on the continental shelf during the Late Pleistocene to evaluate the influence of glacial cycles on sediment erosion and routing to the continental shelf. Taking advantage of the contrasting bedrock ages exposed across the Southern Alps, New Zealand, we perform 40 Ar/ 39 Ar incremental heating on the bulk silt-size sediment from three drill sites of IODP Expedition 317, Canterbury Basin, New Zealand. The results suggest that a large proportion of sediment accumulating on the continental shelf results from erosion within the Main Divide fault zone of the Southern Alps. Sediment 40 Ar/ 39 Ar age fluctuations over this time period suggest that bedrock with various 40 Ar/ 39 Ar cooling ages has been differentially eroded in the upper Waitaki River catchment and mixed in the Waitaki–Canterbury sediment-routing system. Across-shelf variations in sediment 40 Ar/ 39 Ar age reflect changing modes of sediment dispersal on the continental shelf. Fluvial material, likely derived from the main drainage divide zone, preferentially accumulates in the middle continental shelf, whereas material representing erosion of older bedrock (Torlesse Terrane), located lower in the drainage basin, is dispersed uniformly across the shelf. The age signature of the muddy sediment accumulating on the continental shelf reflects Late Pleistocene landscape evolution of the Southern Alps and its influence on sediment dispersal to the continental shelf. [ABSTRACT FROM AUTHOR]

Using bathymetric and seismic data, this study describes the morpho-sedimentary features in Qiongdongnan basin and southwest Taiwan collision basin, northern South China Sea and reveals the linkages between sediment routing system and basin types. The modern Central Canyon in the Qiongdongnan basin is located along the rift margin, and subparallel to the shelf-break southeast of Hainan Island. The modern Central Canyon develops along the basin axis (i.e., Xisha Trough) and longitudinally transports sediments eastward which are mainly supplied by northern continental slope. The Penghu Canyon in the southwest Taiwan collision basin is located along the collision boundary parallel to the strike of the adjacent uplifted Taiwan orogen. The Penghu Canyon develops along the tilting basin axis transporting sediments longitudinally southward to the deep-sea basin and Manila Trench. The Penghu Canyon is supplied with sediments from both flank Kaoping and South China Sea slopes where tributary canyons and channels transport sediments down-slope and feed the axial canyon. The certain basin types may be occupied by particular styles of sediment routing system. By comparing the morpho-sedimentary features and basin characteristics associated with the modern Central Canyon to that of the Valencia Channel in NW Mediterranean Sea, the longitudinal sediment routing system in rift basin type can be determined. In contrast, the longitudinal sediment routing systems in collision setting can be represented by the comparable examples of Penghu Canyon in southwest Taiwan collision basin and Markham Canyon in western Solomon Sea. The rift type sediment routing system is characterized by an axial canyon with a single sediment supply from land drainage margin. In contrast, sediment routing system in collision type basins consists of an axial canyon and dual sediment supplies from flank adjacent slopes. The axial canyons in collision basins are more active than that of the rift basin due to abundant sediment supply and active tectonics. The results demonstrate the role of longitudinal sediment transport in delivering terrestrial sediments for a long distance from land drainages (source) to far-field deep-sea basin (sink). This study has implication for better understanding of the linkages between basin mechanics, sediment routing systems and sedimentary processes. [ABSTRACT FROM AUTHOR]

The regionally correlated and dated regolith–paleolandform sequence of Sub-Saharan West Africa offers a unique opportunity to constrain continental-scale regolith dynamics as the key part of the sediment routing system. In this study, a regolith mapping protocol is developed and applied at the scale of Southwestern Burkina Faso. Mapping combines field survey and remote sensing data to reconstruct the topography of the last pediplain that formed over West Africa in the Early and Mid-Miocene (24–11 Ma). The nature and preservation pattern of the pediplain are controlled by the spatial variation of bedrock lithology and are partitioned among large drainage basins. Quantification of pediplain dissection and drainage growth allows definition of a cratonic background denudation rate of 2 m/My and a minimum characteristic timescale of 20 Ma for shield resurfacing. These results may be used to simulate minimum export fluxes of drainage basins of constrained size over geological timescales. Background cratonic denudation results in a clastic export flux of ~ 4 t/km 2 /year, which is limited by low denudation efficiency of slope processes and correlatively high regolith storage capacity of tropical shields. These salient characteristics of shields' surface dynamics would tend to smooth the riverine export fluxes of shields through geological time. [ABSTRACT FROM AUTHOR]

In order to tackle the relationship between the exhumed Taiwan Orogeny and the associated sediment routing systems, new results from zircon fission track (ZFT) dating, calcareous nannofossil biostratigraphy, and the occurrence of the diagnostic magnetic mineral pyrrhotite in modern and ancient syn-orogenic sediments from pro-foreland basins in western Taiwan are reported. The ZFT age spectra of modern river sediments correspond well to the thermochronometric ages of exposed bedrock and indicate a rapidly exhumed source with a young ZFT peak age of 1.7 Myr in central Taiwan, which has not been widely reported. ZFT results from the Pleistocene successions show diachronous deposition of totally-reset zircons from south to north, accompanied by a trend of younging up-section. The progression of these ZFT signals in conjunction with changes in petrography and pyrrhotite occurrence suggest transient developments of sediment routing systems in central Taiwan and the importance of paleo sediment routing systems. In the Dadu River, totally-reset zircons did not appear until 1–0.45 Myr, when the flux of thermally mature material became prominent. The course of the Choshui river migrated during the past 1 Myr and the reorganization of the river reflects activity of frontal thrusts in Pleistocene times. Exhumation rates recorded by detrital sediments of the Choshui River catchment have been consistently higher than those of the Dadu River, suggesting inherited heterogeneity of exhumation in the orogen. • Modern and ancient pro-foreland deposits of Taiwan were subjected to ZFT, calcareous nannofossils, and pyrrhotite studies. • Detrital ZFT spectra revealed reorganization of sediment routing systems in central Taiwan. • ZFT spectra of modern sediments recognize fast exhumed source areas with the young 1.7 Myr peak age. • Differences of exhumation rates suggest heterogeneity of unroofing between catchments. [ABSTRACT FROM AUTHOR]

The present study is an attempt towards understanding the sediment routing system in the semi-arid margin of the Gulf of Kachchh, which is one of the largest macrotidal regimes in the northern Arabian Sea. Investigations based on heavy minerals, clay minerals, mineral magnetic properties and sediment geochemistry indicated that there are three major sources of sediments contributing to the Gulf of Kachchh basin: (1) Indus River, (2) Kachchh mainland coastal rivers and (3) the Saurashtra peninsular coastal rivers. The flanks of northern and southern coast of western Gulf of Kachchh show dominant signatures of Kachchh mainland/Saurashtra peninsular provenance. In contrast, the eastern Gulf of Kachchh coast bearing fine grained sediments shows dominant Indus River Provenance. Although ephemeral in nature, the small coastal rivers of Saurashtra and Kachchh contribute significant amount of sediments to the Gulf of Kachchh coastline because of their 'dryland' nature and thus they control the coarse grained sedimentation processes. [ABSTRACT FROM AUTHOR]

Cenozoic passive margin sediments in Taiwan provide an important natural archive to reconstruct drainage reorganization in eastern China. In this study, we used Pb isotope compositions of detrital K-feldspar to investigate the sedimentary provenance of Cenozoic strata in Taiwan and to constrain fluvial system evolution in eastern China. Eocene to lower Oligocene sandstones in Taiwan are characterized by radiogenic K-feldspar grains (206Pb/204Pb>18.4), indicating that the eastern Cathaysia Block served as the dominant sediment contributor. In contrast, a late Oligocene sample has a Pb isotopic character indistinguishable from that of the Gan River, a major tributary of the Yangtze River. This provenance change is interpreted as the result of headward (westward) migration of the paleo-Min River to the Wuyishan (Wuyi Mountains) during the late Oligocene. Miocene deposits are enriched in relatively unradiogenic K-feldspar (206Pb/204Pb<17.0) which can be reliably traced back to the Dabie and Sulu orogenic belts. Since the early Miocene, the paleo-Yangtze River, mainly draining the Yangtze Craton and the Dabie orogenic belt, delivered a large volume of detritus to the East China Sea Shelf Basin and also to the proto-Taiwan region. [ABSTRACT FROM AUTHOR]

This study investigates the sediment fluxes through the Yellow River sediment routing system, which are among the largest in the world, by constructing a sediment budget of the system over the period from 1855 to 1968. The framework of the sediment budget includes four functional units with the upper and middle reaches of the river as the sediment source and its lower reaches, its delta, and the deep sea as the sediment sinks. Sediment yield from the source and amounts of deposition in the lower Yellow River and the modern Yellow River delta were estimated for completing the sediment budget. The sediment budget produced for the period from 1855 to 1968 was characterized by a sediment input of 1.837 × 1011 tonnes and a distribution of the sediment between the lower Yellow River, the delta, and the deep sea of 64%, 33%, and 3%, respectively. The details of the sediment budget show that the importance of sedimentation in the lower Yellow River changed greatly with variations in the condition of the dykes and other human activities. A comparison of the sediment budgets of the delta for different timescales shows that the proportion of sediment dispersed to the deep sea decreases as the timescale over which the sediment fluxes are investigated increases. [ABSTRACT FROM AUTHOR]

Reconstructing sediment load in deep-time is one of the greatest challenges in the reconstruction of ancient sediment routing systems, particularly because solid statistical models are absent and paleo-climatic, paleo-tectonic, and sedimentary constraints are lacking. This study proposes a reliable workflow for the estimation of paleo-sediment fluxes (Q s) applying the BQART model to a case study from the SE Germanic Basin across the Middle Permian – Early Triassic interval. The input parameters of the simulations derive from: integrated plate modelling and structural kinematics; paleodrainage and paleogeographic reconstructions; global circulation models; and sandstone compositional signatures. We apply Monte Carlo simulation to overcome the input uncertainties for eight different scenarios obtained from the combination of two area estimates, two climate models, and two time resolutions. All the models are in general agreement and show changes in sediment flux (i) being steady or declining slightly through the Middle Permian, (ii) an increase of 31% at the beginning of the Late Permian (3.6–4.6 Mt yr−1), (iii) and a nearly 100% rise at the onset of the Early Triassic (7.4 Mt yr−1). The variation of sediment load across the PTB is coeval to the transition from meandering/sabkha to perennial braided depositional settings recorded from the well data of Obernsees-1 and Lindau-1; it results from both increased tectonism and seasonal precipitation. The Q s estimates agree with those of modern drainages under analogous environmental conditions, highlighting the reliability of the workflow included in this study for the quantification of sediment flux in deep time. Furthermore, the results of this study provide new insights on the highly debated evolution of the continental sequences across the PTB with strong implications for both past and future paleo-environmental reconstructions. • Integrating paleoclimatic and paleogeographic models to infer sediment fluxes. • Effectiveness of the BQART model in deep-time applications. • The overall sediment load doubles across the Permian-Triassic transition. • Q s estimates are constrained by sedimentological evidence and modern analogues. • Deducing forcing controls on the sedimentary evolution across the PTB. [ABSTRACT FROM AUTHOR]

The need to predict accurately the volume, timing and location of sediments that are transported from an erosional source region into a basin-depocentre sink is important for many aspects of pure and applied sedimentological research. In this study, the results of three widely used methods to estimate sediment flux in ancient sediment routing systems are compared, using rich input datasets from two systems (Eocene South Pyrenean Foreland Basin, Spain and late-Pleistocene-to-Holocene Gulf of Corinth Rift Basin, Greece) for which mapped, dated sediment volumes provide an independent reference value of sediment accumulation rates. The three methods are: (1) the empirical BQART model, which uses values of drainage basin area, relief, temperature, lithology and water discharge; (2) empirical scaling relationships between characteristic geomorphological parameters of sediment-routing-system segments; and (3) the "fulcrum" model, which uses the palaeohydrological parameters of trunk river channels to estimate downsystem sediment discharge. The BQART model and empirical geomorphological scaling relationships were originally developed using modern sediment routing systems, and have subsequently been applied to ancient systems. In contrast, the "fulcrum" model uses hydrological scaling relationships from modern systems, but was developed principally for application in ancient systems. Our comparative analysis quantifies the sensitivity of the three methods to their input parameters, and identifies the data required to make plausible estimates of sediment flux for ancient sediment routing systems. All three methods can generate estimates of sediment flux that are comparable with each other, and are accurate to at least one order of magnitude relative to independent reference values. The BQART model uses palaeoclimatic and palaeocatchment input data, which are accurate for sub-modern systems but may be highly uncertain in deep-time systems. Corresponding estimates of sediment flux are most sensitive to the accuracy with which the palaeocatchment area is constrained and to palaeoclimatic parameters that reflect temperature and precipitation. The "fulcrum" model uses palaeohydrological input data; its sediment-flux estimates are sensitive to palaeochannel dimensions and, in particular, the duration of bankfull discharge, which is invariably difficult to constrain accurately in deep-time sediment routing systems. This uncertainty can give rise to large potential ranges of sediment-flux estimates. Geomorphological scaling relationships offer comparable, order-of-magnitude accuracy for both sub-modern and deep-time sediment routing systems in which geomorphological segments can be identified, but when used on relatively small sediment routing systems the ranges of sediment volumes deposited can vary greatly, limiting the utility of the technique. We suggest that methods to estimate sediment flux should be chosen for a particular sediment routing system based on the types and uncertainty of available data. Where input parameter values are highly uncertain, such as in deep-time systems, Monte Carlo simulation is an effective tool to calculate probability distributions of estimated sediment flux. [ABSTRACT FROM AUTHOR]

Submarine canyons, classified as shelf-incision and slope-confined types, are considered as the most important sediment transportation conduits in the continental margins. Being one of the obvious submarine landforms in the northern continental slope of the Pearl River Mouth Basin (PRMB) in the northern South China Sea, the Shenhu Submarine Canyon Group (SSCG) is composed of 17 NW-SE oriented slope-confined submarine canyons. The SSCG serves as a routing system for delivering large volume of terrestrial sediments, which generate canyon infillings and was deposited further toward the basin. Using the high-resolution bathymetric and seismic data, the geomorphologic features and internal architectures of these slope-confined submarine canyons have been quantitatively analyzed and described in this study. Based on the differentiations in geomorphologies, four canyon segments could be divided from north to south, including upper, middle and lower reaches, and the canyon mouth area. Corresponding to the geomorphological segmentation of these submarine canyons, the variations in the Quaternary infillings were also interpreted clearly downstream, revealing the interaction between gravity flows along the canyon axis and lateral sediment transportation by mass movements. Supported by variation in geomorphologies, infilling characteristics and thickness of the Quaternary sediments from north to south, the sedimentary processes in the different segments of the slope-confined submarine canyons could be documented as erosional-dominant processes in the shelf-edge to the upper slope and depositional-dominant processes in the toe area. The head area of the Pearl River Canyon (PRC) is characterized by the thinner Quaternary strata and shallow-incised small-scale channels. In addition, no considerable change of Quaternary sediment thickness is observed from upper-middle reach of the PRC in other large-scale submarine canyon in the PRMB, indicating lower rate of sediment accumulation and limited sediment redistribute to deep-water basinfloor. Previous study envisaged by Ding et al. (2013) demonstrated the main contribution of the SSCG to deep-sea basins. In this study, we confirm that the SSCG were proposed as the major sediment routing system within the PRMB, which transport abundant terrestrial sediments from the Pearl River Delta via shelf and upper slope in the north to the deep-sea environments in the south. • Shenhu Submarine Canyon Group is the dominant sediment transportation conduits in the Pearl River Mouth Basin. • Slope-confined submarine canyons change from erosion to depositional dominance from north to south. • Terrestrial sediments accumulate in canyons as mass flow deposits and turbidites. [ABSTRACT FROM AUTHOR]