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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]

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]