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This paper summarizes a project seminar in analytical chemistry that includes a method comparison approach and collaborative learning. In this project seminar, 12 students worked in four groups, each of which focused on one method for quantitative element analysis, including flame atomic absorption spectroscopy, inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, and X-ray fluorescence spectroscopy. The seminar was structured into two phases. In the first phase, students became familiar with their method and instrumentation through characterizing the method's capabilities for the analysis of a steel reference sample and then sharing and comparing results between groups. In the second phase, all groups used insights gained during the first phase to design and perform experiments with their methods to solve an analytical challenge. Specifically, the aim of each group was to quantify major, minor, and trace element concentrations from periglacial sediment layers from the hills southeast of Zürich, Switzerland. At the end of phase two, the student-groups presented and compared their results in a joint public poster presentation. Assessment was based on material produced by the participants: posters, teaching materials, method profiles, and written reports. The course evaluation indicates a high satisfaction with the course. The student-centered approach enabled students to get extensive hands-on experience in order to acquire subject-specific skills as well as soft skills. It is well-suited for upper-level undergraduate and graduate students for specialization in analytical chemistry. Further insights, observations, potential for improvement, and limitations are discussed.

Downstream pebble variability in river systems is assessed through various methods, with recent emphasis on efficient, time-saving semi-automatic processes involving photography and digital analysis. The Inaouène valley, however, lacked a comprehensive survey of its main channel using either manual or image-based methods. This study bridges this gap by combining both approaches to analyze the downstream evolution of surface pebbles' morphometric parameters along approximately 60 km of the Inaouène's middle reach. Our research focuses on two key aspects: grain size and particle shape. Results reveal a general downstream trend of size fining, increasing circularity and decreasing elongation, primarily attributed to abrasion and travel distance. Notably, this pattern is interrupted by localized variations associated with tributary inputs and sediment recycling processes. This study significantly contributes to the understanding of fluvial sediment dynamics in the Inaouène Valley. Its findings have broad implications, supporting ecological assessment and restoration efforts, while also informing decision-making in river engineering and management. By providing a comprehensive analysis of pebble characteristics and their downstream evolution, this research establishes a foundation for future geomorphological studies and practical applications in river system management. [ABSTRACT FROM AUTHOR]

The formation age of the middle Yellow River and the existence of a northward‐flowing river have been fiercely debated. The age distribution of detrital zircon varied spatiotemporally and produced contradictory provenance interpretations. The Jinshaan Gorge, the main part of the middle Yellow River and key to studying fluvial evolution and clarifying disputes, developed its topography during the late Cenozoic. In this study, we systematically review the Cenozoic tectonic evolution of the North China Craton, perform detrital zircon U–Pb dating in the Neogene−Quaternary sediments and investigate the topography along the Jinshaan Gorge, and the sedimentology and chronological framework of these sediments. We propose that the Gorge of the middle Yellow River could have developed since the Neogene, controlled by the tectono‐geomorphologic evolution of the North China Craton in a dominantly extensional environment. No evidence supports a northward‐flowing river during the Early Pleistocene or even earlier in the Jinshaan Gorge. We attribute the provenance variations of the Cenozoic sediments to detrital mixing of diverse geological units, local and distant, and especially highlight the systematic provenance shift between the Neogene and Quaternary sediments caused by bedrock downcutting and recycling aeolian sediments. The increased 1.5−0.33 Ga component of the lower Yellow River during the Early Pleistocene was likely caused by enhanced loess accumulation and should not be individually used as a proxy for the Yellow River formation. We emphasize the significance of a comprehensive study of river evolution. Plain Language Summary: Three‐quarters of the Yellow River channel is located on the North China Craton, but the formation and evolution of the Yellow River have been usually attributed to the upper reaches due to the growth of the Tibetan Plateau. Geological units, such as aeolian deposits have a significant impact on the fluvial sediments of the Yellow River, and only systematic work can help unraveling their provenance and potential recycling. We have found that the tectonic evolution of the North China Craton between the rigid Ordos Block and the Lvliang Shan controlled the initial entrenchment of the Jinshaan Gorge in the middle Yellow River since the late or maybe the early Miocene. We have also revealed the complex spatial provenance changes of the fluvial sediments along the Yellow River and the systematic provenance shift between the Neogene and Quaternary sediments. At the same time, we emphasize the significance of an integrated study combining tectono‐geomorphic features, sedimentology and quantitative analysis, such as provenance, for the reconstruction of the river geological evolution. Key Points: The middle Yellow River has developed under the extensional tectonic evolution of the North China Craton since the CenozoicSystematic provenance shift between the Neogene and Quaternary sediments was caused by bedrock downcutting and aeolian depositionDetrital signal from the Tibetan Plateau cannot be transported to and detected in the lower Yellow River [ABSTRACT FROM AUTHOR]

At the end of the Miocene, the European Alps ceased outward expansion, and tectonic uplift and exhumation shifted into the orogen interior. This shift is consistent with a change from orogenic construction to orogenic destruction, reflecting an increase in the ratio of erosional flux to accretionary flux. The coincidence of this change with an increase in sediment yield from the Alps suggests a climate-driven increase in erosional flux. The timing of deformation and sediment release from the southern Alps indicates that the tectonic change occurred synchronous with the last phase of the Messinian salinity crisis. We attribute the increase in erosional flux to a climatic shift to wetter conditions throughout Europe, likely augmented by the base-level fall that occurred during the Mediterranean dessication. This climate change is represented in the stratigraphic record by the Lago Mare deposits of the Mediterranean salinity crisis. Keywords: Mediterranean salinity crisis, European Alps, Miocene, climate, erosional flux, accretionary flux.

Stratigraphic, structural, and fission track data have been integrated in order to unravel the Neogene to Quaternary tectonic evolution of northeastern Corsica. Results indicate that during early to middle Miocene the study area was affected by a rapid cooling at low temperatures accompanied by exhumation and rifting. Basin inversion occurred during the Tortonian, again followed by extension in the Messinian to early Pliocene. Compressional deformations are finally recorded by early Pliocene to Quaternary deposits. Alternating rifting and inversion events are recorded not only in northeastern Corsica but also in many peri-Tyrrhenian regions. This alternation can be explained in terms of intraplate propagation of the compressional stress related to the Africa-Europe convergence and to a discontinuous slab retreat along the Apennine subduction system. A pause in the slab retreat implies a break of the back are extension in the upper plate, and it allows a temporary propagation of Africa-Europe compression.

A description is presented of the Northern Apennine thrust wedge, which was formed by collisions of the Adriatic and European continental plates. Research shows similarities to paleosurfaces of the Early Pliocene era.