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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]

Based on the contents of six heavy metal elements in surface sediments from coastal areas of Fujian Province, the distribution characteristics and controlling factors of six heavy metals in a bay-island-estuary system (BIES) were studied. This paper focuses on the influence of the hydrodynamic environment, and systematically discusses how grain size compositions, chemical environment, tidal current, ocean circulation and human activities influence the distribution and transportation of the heavy metals. The results indicated that the distribution and migration of Cu, Pb, Zn and Cr elements were mainly controlled by natural factors such as regional geological background, grain size compositions, and tidal residual currents. In contrast, As and Hg was mainly affected by human factors such as agriculture and industrial manufacturing. In the BIES, where the chemical environment exerted limited influence, the accumulation and migration of heavy metals are mainly influenced by human activities and enhanced by estuary processes as well as the complex sedimentary dynamic environment caused by many bays and islands. [ABSTRACT FROM AUTHOR]

The grain size, nutrients, and metals contents of sediments are important tracers for reconstructing the origin of the contaminants and the pathway of the sediments from the source to the sink. This is particularly important in areas with high geological variability and a high demographic pressure. The origin and distribution of contaminants and nutrients allow us to identify the source-to-sink pathway of the sediments. In particular, the Sarno River is one of the main contributing sources of anthropogenic contaminants due to the outflow from the large surrounding large industrial area. Geochemical and physical parameters of sediments were analyzed along a transect from the coastline to a water depth of 112 m, with the objective of exploring the spatial variability of sediment contamination in the continental shelf of Naples Bay. The latter is characterized by a complex geological area and is subject to river inflow from a highly industrialized area. The data have been analyzed using principal component analysis (PCA), hierarchical correlation analysis (CA), and analysis of variance (ANOVA). To distinguish between a natural and anthropogenic origin of contaminants and to construct the source-to-sink pathway, the relationship between geochemical and physical data and their distribution was examined, and the results were compared with published data collected onshore. Four distinct sectors with different associations of metals, grain size, and total organic carbon have been recognized: I) offshore Vesuvius volcano, the occurrence of coarse-grained sediments, associated with As, Fe, Mn, and low TOC values, suggests a natural origin of the contaminant due to the volcanic nature of the substrate; II) offshore the Sarno River, the presence of Cr, Cd, Cu, Pb and Zn, associated with the high TOC content, suggests an anthropogenic origin for the contaminants; III) offshore Sorrento Peninsula, the presence of As, Fe, Mn, and some gravel made up of pumice and bioclasts indicate a predominance of contaminants of natural origin; and IV) finally, the distal part is not subjected to a primary terrestrial input. Metals contamination of anthropogenic origin and the organic matter in sediments decreased rapidly with distance from the coast highlighting the main deposition area close to the river discharge.

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]

Riverine export of petrogenic organic carbon (OC petro) from continents to coastal oceans is a dynamic component of the global carbon budget and affects the long-term atmospheric carbon reservoir. In large fluvial systems, oxidation of OC petro during transit releases a large flux of carbon dioxide to the atmosphere, influencing climate changes; however, the transport and fate of OC petro and their controls along the fluvial–marine transition remain poorly constrained. Here, we combined Raman spectral, radiocarbon activity (F14C), mineralogical, and sedimentological techniques with multiple geochemical analyses to characterize the dynamics of OC petro in the water column and sediment particles from the Yangtze River channel–estuary–shelf continuum systems. Our data show that much of the OC petro present in suspended sediment (POC petro) exported by the Yangtze River is "labile" fractions (mostly disordered materials) that can be degraded or lost during transport across the estuarine continuum, whereas the OC petro deposited in seabed sediment are characterized by highly recalcitrant, unreactive, and graphitic carbon phases. As discrete "free" particles, coarse plant debris (>63 μm) with ages of several thousand years observed in the proximal delta of the Yangtze River exhibit nearly identical characteristics of disordered materials, and the presence of aged vascular plant detritus (carbon-rich and 14C-depleted materials) may lead to an overestimate of OC petro in marine sediments. Using a Bayesian endmember mixing approach, a binary mixing model, and the ratio of fraction modern carbon (F14C) to Al/OC, we found a large decrease in POC petro concentration and loading from the suspended sediments to seabed sediments, suggesting a loss of mineral-bound OC petro fraction during sediment transport through the estuary and deposition on the shelf. We estimated that, on average, 46 ± 35 % of the POC petro initially present in suspended sediments delivered to the Yangtze River Estuary during a flood event was primarily oxidized at the sediment–water interface, leaving the most graphitic carbon components transported laterally and efficiently reburied in shelf sediments. We found that during estuarine mixing, flocculation process-induced microaggregates may provide transient physical protection for POC petro in the form of inclusions/aggregates with carbonate minerals; however, when POC petro is physically and chemically separated from its mineral matrix via disaggregation and dissolution, it may be easily oxidized by microbial activity. In contrast, OC-phyllosilicates interactions exert a first-order control on the preservation of OC petro in marine sediments. Our findings suggest that the importance of POC petro oxidation and loss in carbon cycling and budget assessments of estuaries may be underestimated. [ABSTRACT FROM AUTHOR]

Well-log and three-dimensional (3D) seismic data are used to investigate the tectonic controls during the depositional periods of the Kongdian and Shahejie formations from Ek–Es4L to Es4U–Es3L–M on strata distribution, depositional systems and sediment dispersal in the Qingdong Sag, Bohai Bay Basin, East China, from a source-to-sink perspective. This tectonic transition is characterised by the Tanlu Fault switching from sinistral to dextral strike-slip as the fault system changed from a dominant NW–WNW trend during the Ek–Es4L period to a dominant WNW–EW trend during the Es4U and Es3L–M periods. These changes subsequently controlled the framework and areal extent of sediment dispersal in the inner-basin source-to-sink systems and resulted in a change in trend of inner-basin secondary structural belts, from primarily being NW-trending during the Ek–Es4L period to E–W-trending during the Es4U and Es3L–M periods. The tectonic transition also resulted in the western and southern source-to-sink systems expanding with time and controlled the flow path and sediment redistribution within each source-to-sink system with migration of the subsidence centre of the Qingdong Sag and even the region. The significant changes in the basin structure controlled the source area, flow path, sediment transport distance and direction, and have a significant impact on the interpretation of depositional environments and reservoirs in rift basins with a multi-phase evolution history. The Qingdong Sag, Bohai Bay Basin, experienced a tectonic transition during sediment deposition in the Eocene. The tectonic transition resulted in changes to the fault system and basin geomorphology. Fault movement and changes in basin geomorphology affected source-to-sink systems. [ABSTRACT FROM AUTHOR]

The Jacuí Delta drains into Lake Guaíba which is the main source of water for more than two million people in South Brazil and has suffered from pollution with heavy metals and phosphorus. The objective of the current research is to demonstrate how the use of sediment source tracing techniques, in combination with sediment flux monitoring, can improve understanding of the sediment source contributions to one of the largest lakes in South America. The sediment flux monitoring results were based on data obtained from 12-years of records of water flow and suspended sediment concentrations. The sediment source fingerprinting approach was based on the use of geochemical tracers. Based on the study, the respective contributions of the tributaries to the sediment in Lake Guaíba were estimated to be as follows: the Jacuí River (median of 54% - interquartile range (IQR) 34–71%), the Caí River (12%, IQR 7–16%), the Sinos River (5%, IQR 1–20%), and the Gravataí River (16%, IQR 10–30%). These results are similar to those derived from the sediment flux monitoring, namely: the Jacuí River (70%), the Caí River (19%), the Gravataí River (4%), and the Sinos River (7%). These results demonstrate that the sediment source fingerprinting approach combined with sediment flux monitoring can provide a useful means of estimating the respective sediment contributions from individual tributaries in large and complex delta systems and may provide a powerful tool to guide water resource management. [ABSTRACT FROM AUTHOR]

Purpose: Erosion and its spatial distribution in three agricultural headwater catchments were assessed in the border of the volcanic plateau in Southern Brazil. We analyzed terrain, hydrological processes, and land use influence to provide a comprehensive assessment of the catchments' sensitivity to erosion. Methods: Topographic attributes were acquired from a digital elevation map, WaterSed model was parameterized to simulate runoff, diffuse erosion, and sediment yield, and sediment source contributions were estimated using sediment fingerprinting based on near-infrared spectroscopy. Results: According to the modeled results, areas covered by crop fields, grasslands, and those adjacent to the drainage network are the most sensitive to erosion. Short distances from the source to the river network and the occurrence of high magnitude rainfall events (80 mm) promoted increases in connectivity for runoff/sediment transfer. Erosion simulations show that areas of low infiltration, such as unpaved roads, were important runoff generators during lower volume rainfall events (25 mm). Sediment fingerprinting provided satisfactory results to quantify the contributions of unpaved roads to sediment (~ 39%). Topsoil and stream channels were also significant sediment sources for the set of analyzed samples, corresponding to average contributions of 38 and 23%, respectively. Conclusion: Areas sharing geomorphological similarities did not lead to similar sediment contributions. Vegetation cover controlled erosion in topographically sensitive areas. Unpaved roads provide a significant sediment source, followed by topsoil and stream channels. The complementary results provide useful insights to better coordinate planning environmental conservation strategies in these fragile landscapes. [ABSTRACT FROM AUTHOR]

Phloem loading and transport are fundamental processes for allocating carbon from source organs to sink tissues. Cotton (Gossypium spp.) has a high sink demand for the cellulosic fibers that grow on the seed coat and for the storage reserves in the developing embryo, along with the demands of new growth in the shoots and roots. Addressing how cotton mobilizes resources from source leaves to sink organs provides insight into processes contributing to fiber and seed yield. Plasmodesmata frequencies between companion cells and flanking parenchyma in minor veins are higher than expected for an apoplastic loader, and cotton's close relatedness to Tilia spp. hints at passive loading. Suc was the only canonical transport sugar in leaves and constituted 87% of 14C-labeled photoassimilate being actively transported. [14C]Suc uptake coupled with autoradiography indicated active [14C]Suc accumulation in minor veins, suggesting Suc loading from the apoplast; esculin, a fluorescent Suc analog, did not accumulate in minor veins. Of the nine sucrose transporter (SUT) genes identified per diploid genome, only G hSUT1-L2 showed appreciable expression in mature leaves, and silencing GhSUT1-L2 yielded phenotypes characteristic of blocked phloem transport. Furthermore, only G hSUT1-L2 cDNA stimulated esculin and [14C]Suc uptake into yeast, and only the G hSUT1-L2 promoter caused uidA (β-glucuronidase) reporter gene expression in minor vein phloem of Arabidopsis thaliana. Collectively, these results argue that apoplastic phloem loading mediated by GhSUT1-L2 is the dominant mode of phloem loading in cotton. [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]

Dating recent sediment archives (<150 years) constitutes a prerequisite for environmental and climatic reconstructions. Radiocaesium (137Cs) emitted during thermonuclear bomb testing (~1950 ?1980) and nuclear accidents, as well as the decrease of excess lead-210 (210Pbxs) with depth are often combined to establish sediment core chronology. Although these methods have been widely used during the last several decades, there is a lack of structured and comprehensive worldwide synthesis of fallout radionuclide analyses used for dating sediment cores in environmental and Earth sciences. The current literature overview was based on the compilation of 573 articles published between 1977 and 2020, reporting the collection of 1351 individual dating sediment cores (the dataset can be accessed at https://doi.pangaea.de/10.1594/PANGAEA.931493). This review was conducted in order to map the locations where 137Cs fallout events were detected. These included the thermonuclear bomb testing peak in 1963, the Chernobyl accident in 1986, the Fukushima accident in 2011, and 24 additional events identified in 112 sites that led to local radioactive releases (e.g. Sellafield accidents, Chinese nuclear tests). When 210Pbxs records were used along with 137Cs data, detailed information on the 210Pbxs age depth models were also synthesized. Multiple information including the core collection method, sediment properties, radionuclide analysis techniques and catchment characteristics were also compiled. With the current growing number of studies analyzing sediment cores and the increasing interest in the deployment of sediment fingerprinting techniques including radionuclides as potential discriminant properties, this spatialized synthesis provides a unique worldwide compilation for characterizing fallout radionuclide sources and levels at the global scale. This synthesis provides in particular a referential of 137Cs peak attribution for improving the sediment core dating and it outlines the main questions that deserve attention in future research as well as the regions where additional 137Cs fallout investigations should be conducted in priority. [ABSTRACT FROM AUTHOR]

Dating recent sediment archives (<150 years) constitutes a prerequisite for environmental and climatic reconstructions. Radiocaesium (137Cs) emitted during thermonuclear bomb testing (~1950 ?1980) and nuclear accidents, as well as the decrease of excess lead-210 (210Pbxs) with depth are often combined to establish sediment core chronology. Although these methods have been widely used during the last several decades, there is a lack of structured and comprehensive worldwide synthesis of fallout radionuclide analyses used for dating sediment cores in environmental and Earth sciences. The current literature overview was based on the compilation of 573 articles published between 1977 and 2020, reporting the collection of 1351 individual dating sediment cores (the dataset can be accessed at https://doi.pangaea.de/10.1594/PANGAEA.931493). This review was conducted in order to map the locations where 137Cs fallout events were detected. These included the thermonuclear bomb testing peak in 1963, the Chernobyl accident in 1986, the Fukushima accident in 2011, and 24 additional events identified in 112 sites that led to local radioactive releases (e.g. Sellafield accidents, Chinese nuclear tests). When 210Pbxs records were used along with 137Cs data, detailed information on the 210Pbxs age depth models were also synthesized. Multiple information including the core collection method, sediment properties, radionuclide analysis techniques and catchment characteristics were also compiled. With the current growing number of studies analyzing sediment cores and the increasing interest in the deployment of sediment fingerprinting techniques including radionuclides as potential discriminant properties, this spatialized synthesis provides a unique worldwide compilation for characterizing fallout radionuclide sources and levels at the global scale. This synthesis provides in particular a referential of 137Cs peak attribution for improving the sediment core dating and it outlines the main questions that deserve attention in future research as well as the regions where additional 137Cs fallout investigations should be conducted in priority. [ABSTRACT FROM AUTHOR]

The Måløy Slope is a key area for studying the connection between onshore and offshore geology of South Norway. It has functioned as an area of bypass, erosion and deposition between the Norwegian mainland source area and the offshore northern North Sea sink area since the Permian. The slope was faulted into N--S-trending rift fault-blocks through flexural down-bending during the large-scale extension and rapid rift basin subsidence in the Late Jurassic and Early Cretaceous. Mapping of 3D seismic data has revealed a profound network of E--W-oriented erosional submarine canyons. These canyons cut up to 500 m into the crystalline bedrock on the rift-related fault-block crests. We suggest that the canyons were first established prior to the faulting associated with late Jurassic rifting. The canyons may have been important feeders in the Oxfordian, Kimmeridgian and Tithonian like canyons in the Uer Terrace to the south, although we lack direct evidence for this. Further erosion and deepening of the canyons into the basement occurred during Cretaceous in a post-rift setting. The position of the main canyons sustained during recurring periods of erosion from the Late Jurassic until burial within the slope in the Late Cretaceous. By the aid of detailed bathymetric maps, the main canyons can be correlated with onshore faults and drainage systems (fjords and valleys). The evolution of the slope canyon system over time is controlled by both tectonic and isostatic movements and, as discussed in the text, can help understand when and where the pre-fjord drainage was established. Multiple incision events have been detected, and each of these express some correlation to regional tectonic events in (1) Late Jurassic--Earliest Cretaceous, (2) Late Aptian--Albian and (3) Turonian--Coniacian. [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]

Both the shelf-edge trajectories and slope morphology are indicative of deep-water sedimentation, but previous studies are relatively independent from each other in the two dimensions. An integrated investigation can enhance the understanding of deep-water sedimentary systems and enrich reservoir prediction methods. Based on the bathymetry data and seismic data published, this study identified ten slope areas at the continental margin of East Africa and classified the clinoforms into three types: concave-up, sigmoidal and planar. Combined with the distribution of main modern rivers in East Africa, nine modern source-to-sink systems were identified and the catchment area is positively correlated with the size of the shelf-edge delta. It is found that the slope morphology of East Africa is closely related to the geological setting, sediment supply and sediment transport pathway in submarine canyon of passive continental margin. When the sediment supply is stable, the concave-up slopes are dominated by the river-associated and shelf-incising canyons and the sigmoidal slopes are determined by the headless canyons. There exists a strong coupling relationship between the shelf-edge trajectories and slope morphology. In general, concave-up slopes correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories and high-quality reservoirs developed on the basin floor under the influence of river-associated and shelf-incising canyons which have bright prospects for oil and gas exploration. Additionally, sigmoidal slopes usually correspond to descending trend, flat and low-angle ascending trend shelf-edge trajectories at times of relative sea-level fall and the reservoirs mostly developed on the upper slope under the influence of headless canyons. Moreover, the planar slopes correspond to high-angle ascending trend trajectories which are hardly potential for exploration. The coupling model built in this study will provide an insight for oil and gas exploration in deep-water areas with limited data and low exploration degree. [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]

In order to meet the increasing demand to decarbonize the atmosphere, storage of CO2 in subsurface geological reservoirs is an effective measure. To maximize storage capacity, various types of saline aquifers should be considered including dynamic storage options with open or semi-open boundaries. In sloping aquifers, assessment of the immobilization potential for CO2 through dissolution and mineralization along the flow path is a crucial part of risk evaluations. The Gassum Formation in the Skagerrak is considered a nearshore CO2 storage option with sloping layers, facilitating buoyant migration of CO2 northwards along depositional and structural dip. In this study, petrographic data and provenance analysis provide the basis for estimating reactivity of the sandstones. Immobilization of CO2 in the reservoir through fluid dissolution and mineral reactions reduces risk of leakage. Petrographic analyses are integrated with seismic and well-log interpretation to identify sedimentary facies and to estimate mineral distribution with corresponding reactivity in the proposed injection area. Here the Gassum Formation comprises south-prograding, shoreface-fluvial para-sequences, sourced from northern hinterlands. Pronounced differences in the mineralogical maturity in the studied area are identified and explained by the sediment transport distances and the type of sediment source. This is possible because the U-Pb ages of zircon grains in the sediments can be used to pinpoint the areas where they originate from in the Fennoscandian Shield, such as the Telemarkia or Idefjorden terranes. Albite and Fe-rich chlorite are identified as the most reactive mineral phases in the Gassum sand, of which feldspar comprises the largest weight fraction and the grain-coating chlorite has largest surface area. Their distribution is partly controlled by provenance, so their abundance decreases basinwards with increasing sediment maturity. The abundance of fluvial sandstones presumably increases northwards in basal parts of para-sequences, while shoreface sandstones comprise the top part of sandy units. CO2 injected in the proposed area will migrate upwards within the reservoir, toward higher proportions of Telemarkian-derived sediment and up-dip along the seal, toward more immature sediments. Thus, the reactivity of sediments increases in younger deposits and up depositional dip, while kinetic reaction rates will decrease in shallower, lower temperature regions. Identifying these parameters is important to estimate the CO2 mineral sequestration potential as a function of sedimentary facies and ensure safe storage of CO2. This approach can advantageously be applied to all reservoirs considered for CO2 injection to improve the estimation of the possible CO2 storage volume by taking the provenance dependence of the mineralization potential into account.

Continental drainage systems archive complex records of rock uplift, source area relief, precipitation, glaciation, and carbon cyclicity driven largely by tectonics and climate. Significant progress has been made in linking such external environmental forcings to the geomorphic expression of landscapes and the stratigraphic record of depositional basins in coastal and offshore areas. However, there are large uncertainties in the degree to which sediment dispersal processes can modify signals between the erosional sources and the depositional sinks. We investigate a Holocene sediment transfer zone with contrasting fluvial and eolian sediment transport mechanisms to understand how river and wind processes impact the propagation of environmental signals in continental-scale drainage systems. To quantify these processes, we employ sediment fingerprinting methods for unconsolidated sand samples (detrital zircon U-Pb geochronology), incorporate sediment mixing models, and correlate the findings with the regional geologic and geomorphic framework. Three contrasting source regions deliver sediment to the Andean foreland: volcanic rocks of the Frontal Cordillera, sedimentary rocks of the Precordillera, and metamorphic basement of the Sierras Pampeanas. Although all samples of Holocene eolian dunes accurately record sediment input from three fluvial source regions, spatial variations in U-Pb results are consistent with north-directed paleowinds, whereby river sediments from Frontal Cordillera sources are transported northward and progressively mixed with river sediments from Precordillera and Sierras Pampeanas sources. In contrast, samples of modern rivers show progressive southward (downstream) mixing along a large axial fluvial system. Sediment mixing induced by eolian transport and reworking of various sources is likely a critical, climate-modulated process in the propagation of environmental signals, potentially involving the aliasing of tectonic signals, local storage and recycling of synorogenic river sediment, and cyclical patterns of sediment starvation and delivery to distal zones of accumulation.

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]

This work presents the first Sm–Nd and Sr isotope TIMS data on the fine-grained fraction (<74 μm) of iron-rich deposits related to the November 5th, 2015 Mariana accident, caused by the rupture of the Fundão dam, an iron tailings pond operated by SAMARCO Mining. The failure of the Fundão dam provoked the gravitational flow of approximately 62 Mi m3 of a quartz and iron oxide-rich slurry composed of water, fine sand and silt, that flowed into the Gualaxo do Norte and Carmo rivers, and eventually along the whole Doce River. Samples were collected between 5 and 80 km downstream from the Fundão Dam, along the Santarém creek and the Gualaxo do Norte and Carmo rivers. XRD analyses show that samples are >90% composed of quartz and iron oxides (hematite, goethite and magnetite), with minor phyllosilicates (kaolinite and mica). Owing to sediment transport processes, heavy (hematite, goethite, magnetite) to light (quartz, phyllosilicates) mineral fractionation is observed. As with XRD data, major and trace element compositions also closely match those of the original Paleoproterozoic Cauê Formation BIF iron ore. The studied samples yielded δ Nd between −17.0 and −19.7 pptt (part per ten thousand), with the exception of one sample, with δ Nd of −23.2 pptt. Strontium 87Sr/86Sr ratios show variability between 0.7351 and 0.7729. The T DM ages scatter between 1.94 Ga and 2.75 Ga, with a negative correlation with phyllosilicate contents, indicating that the latter has preferential provenance from younger, more juvenile sources than the Cauê Fm itabirites. This interpretation is corroborated by two component mixing models of Nd and Sr isotope ratios, where the Nd–Sr isotopic signatures of the studied samples are compatible with >98% of the Cauê Fm itabirite component, mixed with a Neoproterozoic juvenile mafic rocks component, such as those from the ophiolitic assemblages of the distal Macaúbas Group, or tholeiitic mafic rocks of the Pedro Lessa suite. The reported Sm–Nd and Sr isotope compositions closely match those of the original iron ore and contrast with either those of the upriver or downriver Precambrian to Ordovician bedrock units. The firstly defined isotope signature can thus be potentially used as a proxy for ongoing suspended sediment dispersion studies farther downstream along the Doce River and in adjacent marine environment. Image 1 • First Sm-Nd and Sr isotope composition of proximal iron-rich sediment from the Mariana mining accident of November 2015. • Sm–Nd and Sr isotope composition is controlled by phyllosilicate mineral content, which tends to decrease downstream. • Sm-Nd and Sr isotope compositions match those of iron ore and contrast with those of the upriver or downriver bedrock units. • The firstly published signature is a proxy to sediment dispersion downstream along the Doce River and adjacent marine system. [ABSTRACT FROM AUTHOR]

Detrital zircon U/Pb geochronology is a common tool used to resolve stratigraphic questions, inform basin evolution and constrain regional geological histories. In favourable circumstances, detrital zircon populations can contain a concomitant volcanic contribution that provides constraints on the age of deposition. However, for non-volcanic settings, proving isolated detrital zircon grains are from contemporaneous and potentially remote volcanism is challenging. Here we use same grain (U–Th)/He thermochronology coupled with U/Pb geochronology to identify detrital zircon grains of contemporary volcanic origin. (U–Th)/He ages from Cretaceous zircon grains in southern Australia define a single population with a weighted mean age of 104 ± 6.1 Ma, indistinguishable from zircon U/Pb geochronology and palynology (∼104.0–107.5 Ma). Detrital zircon trace-element geochemistry is consistent with a continental signature for parent rocks and coupled with detrital grain ages, supports derivation from a >2000 km distant early- to mid-Cretaceous Whitsunday Volcanic Province in eastern Australia. Thus, integration of biostratigraphy, single-grain zircon double-dating (geochronology and thermochronology) and grain geochemistry enhances fingerprinting of zircon source region and transport history. A distal volcanic source and rapid continental-scale transport to southern Australia is supported here. Image 1 • Integrated thermochronology-geochronology-geochemistry resolves detrital zircon histories. • Coupled (U-Th)/He and U-Pb chronology can help distinguish volcanic zircon components. • Cretaceous zircons on the Madura Shelf rapidly deposited after volcanic genesis. • Madura Shelf zircon trace-elements support an origin in eastern Australian volcanics. • No evidence for Mesozoic volcanism in Bight Basin, southern Australia. [ABSTRACT FROM AUTHOR]

The syn-rift sedimentary history of the Pearl River Mouth Basin (PRMB) in the northern South China Sea is poorly understood due to restricted borehole coverage. In this study, an integrated analysis of 3D seismic data, detrital zircon data and the data from previous provenance studies has been used to document the shifting of provenance and depositional response during the Paleogene Enping Formation of the Baiyun Sag in the PRMB. Our results show that the Baiyun Sag was filled mainly with sediments derived from two potential sources: the intrabasinal source of uplifts in the PRMB (Mesozoic igneous rocks) and the extrabasinal source of the South China Block (Precambrian–Paleozoic metamorphic and magmatic rocks). During the deposition of the lower and middle members of the Enping Formation (EpL–EpM), the sediment of the Baiyun Sag was derived primarily from the intrabasinal source. The sediment was transported over relatively short distance through faulted troughs and incised valleys and deposited in a series of small-to medium-scale braided deltas, beach bars and fan deltas. However, during the deposition of the upper member of the Enping Formation (EpU), the sediment of the Baiyun Sag was derived mainly from a mixture of extrabasinal and intrabasinal sources. The sediment of the EpU was transported over relatively long distance via large-scale incised valleys and deposited in three stages large-scale progradational braided delta. The detrital zircon age spectra of the EpU in the northwestern area show four well-recognized age clusters with peaks at ∼842 Ma, ∼450 Ma, ∼252 Ma and ∼151 Ma, which correspond to tectono-magmatism in the South China Block. The analysis of provenance shifting in this study may be of great value in constraining the tectonic and sedimentary evolution of the PRMB, northern South China Sea margin, as well as the drainage evolution of the paleo-Pearl River. Our findings can also provide potential benefits for the integrated analysis of geophysics and geochronology data through time in the petroliferous basins. Highlights • A useful case study for source-to-sink system based on the integrated analysis of 3D seismic and detrital zircon data. • An important Paleogene provenance shift are identified in the northern South China Sea area. • The South China Block began feeding the Baiyun sag in the early Oligocene, but sediment only reached the northern slope. • The period of Paleogene provenance shift in the Zhu 1 Depression was earlier than in the Baiyun Sag. • Erosion and transportation of sediment from the SCB was limited to the northeastern Pearl River area until late Oligocene. [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]

A unique synthesis of grain size-distance data is presented, comparing, for the first time, grain size and fining trends in a wide range of modern and ancient axial sediment dispersal systems, and tracking grain-size from source to sink across several sedimentary basins. In general, grain-size decreases exponentially with distance down system, and modern and ancient examples fine at broadly comparable rates in similar depositional settings. Linear fining rates vary by eight orders of magnitude, being higher in coarser-grained settings. Very few data sets have a median grain size between 1 and 5 mm in diameter, supporting the idea that material of this calibre is rare. Alluvial fans fine at the highest rates, by up to 450 cm/km (216%/km) in modern and 115 cm/km (427%/km) in ancient examples, but more typically by around 1 to 12 mm/km (87 to 1%/km), whereas fluvial gravels fine by 0.8 to 4 mm/km (0.4 to 5%/km). Sand-prone systems fine more slowly, by a few tens of microns per kilometre or less: 1 to 23 μm/km (0.25 to 2.5%/km) in distributive fluvial systems, ∼1 to 8 μm/km (∼1 to 6%/km) in fluvio-deltaic channels, 0.2 to 44 μm/km (0.08 to 14%/km) in ergs, and from 0.45 to 29 μm/km (0.18 to 7%/km) in basin-plain turbidites. At the basin scale, fining rates increase where gravels pinch out down-system at the fluvial gravel-sand transition, and where sands pinch out at the toe of the shoreface. Modern fluvial gravel-sand transitions are relatively well characterised, with fining rates ranging from 71 to 0.2 mm/km (483 to 2%/km), and lower rates and wider transitions in wider, longer rivers, insights that appear applicable to the rock record. Downstream fining predominantly reflects selective deposition of coarser material and preferential transport of finer grains, with subsidence increasing fining rates as coarser grains are preferentially extracted up-dip to form stratigraphy. Across short segments, grain-size can increase down system as a result of winnowing, bypass, or lateral sediment input. Comminution is largely considered a secondary factor in rivers, but important in ergs, where lateral sediment input can overwhelm downstream fining effects, and grain-size sorting across dunes may obscure longer downwind trends. In deep water, when the slope is bypassed, basin-floor fans can fine at rates comparable to contemporaneous up-dip fluvial channels, by 30 μm/km (5%/km), but if sediment is deposited on the slope, fining rates increase (225 μm/km 75%/km) as distances are shorter. Axial flow lines across basin-plain turbidites with diverse grain-size, and dimension, can be closely comparable on mass-balance plots, suggesting that the properties of one bed could inform predictions of those of another. As yet there are no studies of fining rates in conglomeratic deep-water systems, where the transition from conglomerate to sand-dominated systems is of particular interest, given its importance for fining rates in fluvial systems. The dataset has potential to constrain computer simulation models of sediment calibre, and subsurface models that address, for example, aquifer flow, and petroleum migration. [ABSTRACT FROM AUTHOR]

This paper explores the formation and evolution of high-elevation passive margins, focusing on the morphology and uplift processes of the eastern Red Sea region and its relationship to the stratigraphy of the Red Sea (source-to-sink approach). We address gaps in our understanding of the origin and persistence of erosional escarpments along rifted margins and their connection to continental rifting. To achieve this, the research combines geological observations, geomorphic mapping and reconstructions of past topography to estimate erosion and compare it to accumulated sediment volumes in the basins. The study presents a landform map and an age model of landscape evolution of the Eastern Red Sea Rifted Margin (ERSRM), identifying 4 phases of erosion affecting two separate domains. On the Arabian plateau, remnants of the African surface (S I) and an Oligocene planation surface (S II) were rifted, uplifted and exhumed during rifting, and refreshed (S III) since the onset of seafloor spreading. West of the escarpment, a young (< 15 Ma) foothill belt (S IV) was carved by the eastward retreat of the Arabian Escarpment. We identified three different settings controlling the escarpment evolution and coastal plain morphology along the margin from north to south: (1) escarpment retreat from the rift fault towards the interior in the northernmost Red Sea, (2) escarpment retreat synchronously from two parallel rift faults and capture of a former endorheic drainage system, resulting in the formation of the biggest catchment in western Saudi Arabia (i.e., Wadi Hamd), and (3), escarpment retreat within a downwarped margin in the southern Red Sea, accompanied by sustained flexural uplift. These settings are the result of rift inherited structures segmenting the Red Sea, as well as the effect of the AFAR hotspot fading towards the north around the Jeddah latitude. Furthermore, we demonstrate that the escarpment evolution was not a steady process, as at the end of rifting ∼16 million years ago, erosion rates were high and remain relatively high (although decreasing) up to 5 million years. Then a dramatic drop in erosion rates occurred, documenting the cessation of the escarpment retreat. We link this decrease in erosion and sedimentation rates to a global aridification of the climate throughout the Plio-Pleistocene. Finally, we discuss the complexity of escarpment evolution, both in terms of time and space, mitigating the often simplified vision of linear escarpment evolution. By bridging the gap between onshore geomorphic evolution and coastal basin stratigraphy, this study contributes to a comprehensive understanding of the long-term evolution of rifted margins. [ABSTRACT FROM AUTHOR]

The backwater effect (i.e. adjustments in open-channel flow as a response to proximity of standing water) is used to predict down-dip changes in morphodynamics and consequent sediment distribution on fluvial systems. However, there is currently no standardized method to obtain input parameters to estimate backwater length, nor where to measure these variables, for both modern and ancient settings. This study reviews existing methods for estimating backwater lengths in both settings and proposes workflows to minimize ambiguity in the results. The proposed workflows are prioritized based on practicality, accuracy, and smallest uncertainty ranges and allow different data types as input parameters. For the first time, applying multiple methods to obtain backwater length estimates is tested, both on a modern and ancient river system. In the modern case study, the riverbed intersection with sea level matches previously documented major changes in sedimentary trends. However, backwater lengths based on h/S (h = bankfull thalweg channel depth, S = slope) plot downstream of this zone which is characterized by major changes, when input parameters are derived from discharge and grain size. Therefore, we recommend obtaining bankfull thalweg channel depth from a cross-sectional profile if backwater length is estimated based on h/S. In the ancient case study, bankfull thalweg channel depth derived from fully preserved single-story channel fill and slope based on Shields' empirical relation with grain size, match changes in fluvial architectural style interpreted as a result of backwater effects. This review is a critical step forward in discussing and acknowledging the uncertainties and ambiguity in obtaining the necessary input parameters to estimate and compare modern and stratigraphic backwater lengths. The proposed workflows facilitate comparability and applicability of future backwater length estimates and subsequent interpretations of the hydrodynamic environment and resulting stratigraphic record. Potential scaling relationships between the backwater length, sedimentary trends, and avulsion nodes make this of key importance as the latter two also play a crucial role in devastating floods when rivers change course. [Display omitted] • Backwater length (Lb) predicts changes in channel morphology and sedimentary trends. • Due to input parameter ambiguity, same river Lb estimates may vary a factor 10. • In modern settings, riverbed/sea-level intersection provides the most accurate Lb. • In ancient settings, Lb based on grain size and bankfull thalweg depth is most reliable. • We provide tested workflows to improve uncertainty management and comparability. [ABSTRACT FROM AUTHOR]

Retroarc basins register the onset of compressional exhumation during the Cretaceous in the Andes, evidenced by sequences showing sedimentary provenance from the orogen. We present U–Pb detrital zircon geochronology from the Austral-Magallanes basin in the Southern Patagonian Andes (∼47–48°SL), where the foreland stage began in the Early Cretaceous. The littoral sandstones from basal foreland sequences of the Río Belgrano Formation yield ∼123 Ma maximum depositional ages, confirming previous studies that the basin infill is early Aptian. The detrital zircon ages showed two main clusters of 129-115 Ma and 151 -140 Ma, that are derived from the coetaneously exhumed Andean arc and earlier Jurassic magmatic sources. The zircons which overlap with ages of Upper Jurassic Andean synrift volcanics, confirms orogenic exhumation coeval with sedimentation. A sequence of retroarc volcanism dated between 119 and 97 Ma overlies the basal foreland littoral-continental deposits, and it is followed by a Late Cretaceous-Paleocene hiatus. Further analysis of detrital zircons ages distribution and geological considerations, indicates that the studied northern depocenter was a source region of sedimentary supply after its Cenomanian exhumation. • The northern depocenter of the Magallanes-Austral basin is characterized by Aptian-Albian regressive sequences. • U-Pb geochronology on detrital zircon registering a maximum depositional age for this sequence of 123 Ma. • U-Pb detrital ages between 151 and 140 Ma from Rio Belgrano Formation overlap with ages of Upper Jurassic synrift volcanic. • Exhumation of the synrift sequence allows us to interpret the onset of the uplift of the Patagonian Andes during the Aptian. • The construction of the Andes was diachronic throughout the Patagonia having a tendency to be younger to the south. [ABSTRACT FROM AUTHOR]

Carassai, J.J.; Lavina, E.L.C; Chemale, F., Jr., and Girelli, T.J., 2019. Provenance of heavy minerals for the Quaternary coastal plain of southernmost Brazil (Rio Grande do Sul State). Journal of Coastal Research, 35(2), 295–304. Coconut Creek (Florida), ISSN 0749-0208. During the Quaternary, an extensive barrier system was developed in southern Brazil and northern Uruguay. The patterns of variation in the distribution and behavior of heavy minerals present in the aeolian and marine (upper shoreface-foreshore) facies of the four barriers formed in the Rio Grande do Sul costal plain were identified. Minerals were analyzed by scanning electron microscopy, including epidote, tourmaline, zircon, magnetite/ilmenite, polymorphs of aluminum silicates (andalusite, kyanite, and sillimanite), staurolite, rutile, amphibole, pyroxene, corundum, perovskite, chromite, garnet, apatite, monazite, xenotime, spinel, and titanite. In all of the barriers, zircon, magnetite, and ilmenite are the most important, followed by chromite, garnet, rutile, tourmaline, staurolite, and epidote. In total, heavy minerals indicate two primary sources in the coastal plain: (a) direct feeding from the rocks of Uruguay and Rio Grande do Sul Shield and Paraná Basin, drained by Rio Camaquã and Rio Jacuí; and (b) indirect feeding from rocks of the Andean province, drained by Rio Paraná and Rio La Plata estuary in northern Argentina. During low sea level, rivers flowed directly into the continental shelf, and their deposits were reworked during subsequent transgressive stages. Throughout this region, the atmospheric circulation pattern forms a NW oceanic swell, generating a longshore current with dominant northward direction. Thus, several transgressive-recessive pulses associated with Pleistocene glacial events pushed large volumes of sediments northward, giving rise to the present southern Brazil coastal plain. [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]