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In the case of modern river sediments, source rocks, tectonic setting, and climatic and geomorphological conditions are fully known, diagenetic effects are by definition none, and physical and chemical processes during erosion, transport, and deposition can be investigated directly in any required detail. Their study thus provides the fundamental information needed to understand the impact of various controls on sediment generation and sediment routing systems in diverse geological settings. With the growing interest in source‐to‐sink sedimentary systems for economic purposes, researchers have focused more and more on modern environments, producing an ever‐increasing amount of compositional data on river sediments. To better integrate and utilize these large datasets, we systematically compiled a global database of 4,208 fluvial sediment samples compiled from 100 published papers, book chapters, and dissertations and included 3,747 petrographic and 1,943 heavy‐mineral analyses. The analysed samples are mostly located in Asia, Africa, Europe, and South America, with fewer examples from North America and Oceania. Each sample is complemented by metadata describing references, river name, geographic location, sampling date, analytical method, and grain size, so that samples can be grouped and filtered to meet different needs including comparison with other datasets. We compiled a global database of 4,208 fluvial sediment samples with 3,747 petrographic and 1,943 heavy‐mineral analyses. Each sample is complemented by metadata describing references, river name, geographic location, sampling date, analytical method, and grain size, so that samples can be grouped and filtered to meet different needs. The database provides fundamental information needed to understand the impact of various controls on sediment generation and sediment routing systems in diverse geological settings. [ABSTRACT FROM AUTHOR]

Abstract In the case of modern river sediments, source rocks, tectonic setting, and climatic and geomorphological conditions are fully known, diagenetic effects are by definition none, and physical and chemical processes during erosion, transport, and deposition can be investigated directly in any required detail. Their study thus provides the fundamental information needed to understand the impact of various controls on sediment generation and sediment routing systems in diverse geological settings. With the growing interest in source‐to‐sink sedimentary systems for economic purposes, researchers have focused more and more on modern environments, producing an ever‐increasing amount of compositional data on river sediments. To better integrate and utilize these large datasets, we systematically compiled a global database of 4,208 fluvial sediment samples compiled from 100 published papers, book chapters, and dissertations and included 3,747 petrographic and 1,943 heavy‐mineral analyses. The analysed samples are mostly located in Asia, Africa, Europe, and South America, with fewer examples from North America and Oceania. Each sample is complemented by metadata describing references, river name, geographic location, sampling date, analytical method, and grain size, so that samples can be grouped and filtered to meet different needs including comparison with other datasets.

Detrital zircon U-Pb geochronology is a powerful tool for deciphering Earth' s sedimentary archive, answering a large amount of research questions including sediment provenance and palaeogeographic correlations. Although sound reasons exist to conduct qualitative analysis, the advent of large-n acquisition techniques and readily available statistical tools have provoked a shift towards quantitative analysis as the preferred approach during the last two decades. The assumption for a geologically meaningful interpretation of inter-sample comparison through detrital zircon age distributions is that the analyzed samples are a true reflection of the sediment sampled, and this can be used as a proxy for the relative proportion of crystalline rocks in the source region. However, this foundational assumption may be undermined by a number of biases, leading to controversial interpretations and a risk of abuse of the method. In this paper, we demonstrate the principles of the quantitative provenance analysis using detrital zircon U-Pb geochronology and review five major factors that can add bias to the age spectrum and influence the provenance interpretation. The results show the significance to using modern river sand for testing the fidelity of the detrital zircon geochronology because the zircon fertility, hydrological sorting, and sediment mixing can be better constrained than ancient fluvial sequence. Based on the new technologies, including large-n sampling, rim-core dating, and three-dimensional zircon morphology, the quantitative relationship between sedimentary hydrodynamics and age spectra are established, providing further instruction for the provenance study of deep-time sedimentary strata. [ABSTRACT FROM AUTHOR]

The Pyrenees Mountains are a classic example of a doubly‐verging collisional orogenic system with flanking retro‐ and pro‐foreland basin systems. Previous bedrock and detrital geo‐/thermochronologic studies have observed magmatic and exhumation‐related ages that reflect a complex thermo‐tectonic evolution of the European and Iberian plate margins related to break‐up and assembly of the Gondwana, Pangea and Pyrenean‐Alpine orogenic cycles. This study integrates detrital zircon, rutile and apatite U‐Pb dating and, detrital zircon and apatite (U‐Th)/He dating from modern river sands from the northern and southern Pyrenees, with PECUBE thermokinematic modelling of bedrock cooling ages to simulate detrital age distributions in order to evaluate: (1) regional patterns in long‐term crustal processes associated with pre‐Pyrenean crustal shortening, crustal thinning and magmatism along the Iberian and European plate margin; (2) timing of regional cooling and inferred erosion related to Pyrenean orogenesis; and (3) the exhumation processes associated with post‐orogenic decay and erosion. Modern river multimineral detrital geo‐/thermochronometry results are consistent with previous bedrock thermal history models and records punctuated Variscan and Pyrenean cooling events in the pro‐wedge that contrasts with protracted Permian to Pliocene thermal history preserved in the retro‐wedge of the orogen. Detrital age distributions from PECUBE modelling predict the Pyrenean age component in both detrital apatite and zircon (U‐Th)/He age distributions, indicating the modelled exhumation patterns in the Axial Zone and Northern Pyrenean Zone can predict observed Pyrenean thermochronology ages. The presence of strong Pyrenean age peaks amongst the modern river sand and modelled detrital cooling age distributions suggests retro‐wedge deformation and exhumation remained active during the main phase of pro‐wedge activity and experienced significant orogenic decay. Isolated Miocene apatite He ages from the North Pyrenees modern river record post‐orogenic cooling, due to tectonic mode switch to extension and (or) climate‐driven enhanced exhumation. [ABSTRACT FROM AUTHOR]

OSL (optically stimulated luminescence) sensitivity of quartz has been shown to either (1) record downstream sediment transport related to increased number and duration of light exposure cycles or (2) be a function of source geology, presenting a potential tool to track sediment provenance. To test these competing models this study leverages a suite of modern river samples from an extensional basin system in the Rocky Mountains of western USA (Bear River) and a retroarc foreland basin system in the southern Central Andes of Argentina (Río San Juan) to understand the relationships among quartz luminescence sensitivity, sediment transport distance, and catchment lithologies. We compare our results with petrographic analysis of the river sand composition, and characterization of the lithology and morphometrics of the river catchments. Samples taken along the Bear River and its major tributaries in the Rocky Mountains show a progressive downstream decrease in quartz OSL sensitivity that records variation in sediment provenance and steady contribution of lower OSL sensitivity quartz recycled from Palaeozoic passive margin stratigraphy. Andean river sand samples from the Rio San Juan network exhibit pervasive low sensitivity quartz derived from Andean arc volcanic rocks and recycled Neogene foreland basin strata. These modern river sand data do not show increased sensitivity with transport distance and instead indicates that in these landscapes, quartz OSL sensitivity is an intrinsic property of the source rock. Our study shows that river sands primarily composed of older, recycled low-strained quartz derived from quartzite lithologies exhibit the highest quartz sensitivity values. Moderate quartz OSL sensitivity values are observed in rivers with young igneous quartz derived directly from the volcanic and intrusive rocks. Conversely, microcrystalline quartz in chert lithic grains or polycrystalline quartz found in composite metamorphic lithic grains record the lowest quartz OSL sensitivity values. Determining the controlling factors of quartz sensitivity in river sand provides a current baseline for resolving paleogeographic and paleodrainage histories in the sedimentary record and provides further understanding of how sediments are eroded, transported, and deposited in fluvial systems with diverse tectonic settings and geologic source rocks. [ABSTRACT FROM AUTHOR]