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High‐relief glacial valleys shape the modern topography of the Southern Patagonian Andes, but their formation remains poorly understood. Two Miocene plutonic complexes in the Andean retroarc, the Fitz Roy (49°S) and Torres del Paine (51°S) massifs, were emplaced between 16.9–16.4 Ma and 12.6–12.4 Ma, respectively. Subduction of oceanic ridge segments initiated ca. 16 Ma at 54°S, leading to northward opening of a slab window with associated mantle upwelling. The onset of major glaciations caused drastic topographic changes since ca. 7 Ma. To constrain the respective contributions of tectonic‐mantle dynamics and fluvio‐glacial erosion to rock exhumation and landscape evolution, we perform inverse thermal modeling of a new data set of zircon and apatite (U‐Th)/He from the two massifs, complemented by apatite 4He/3He data for Torres del Paine. Our results show rapid rock exhumation recorded only in the Fitz Roy massif between 10 and 8 Ma, which we ascribe to local mantle upwelling forcing surface uplift and intensified erosion around 49°S. Both massifs record a pulse of rock exhumation between 7 and 4 Ma, which we interpret as enhanced erosion during the beginning of Patagonian glaciations. After a period of erosional and tectonic quiescence in the Pliocene, increased rock exhumation since 3–2 Ma is interpreted as the result of alpine glacial valley carving promoted by reinforced glacial‐interglacial cycles. This study highlights that glacial erosion was the main driver to rock exhumation in the Patagonian retroarc since 7 Ma, but that mantle upwelling might be a driving force to rock exhumation as well. The isotopic system (U‐Th)/He in apatite and zircon record the ages in which a rock experiences relatively low temperatures (200–60°C) at shallow crustal depths (6–1 km). We present a new data set of low‐temperature thermochronometers for rocks of the Fitz Roy and Torres del Paine mountains in the Southern Patagonian Andes. Fast rock cooling can be forced by intensified surface erosion, and/or tectonic and mantle activity. An episode of fast cooling between 10 and 8 Ma was identified in the Fitz Roy mountains, and mantle upwelling forcing surface uplift, combined with high fluvial erosion may have caused fast rock exhumation. A regional episode of fast rock cooling between 7 and 4 Ma causing 1–3 km of exhumation in the Fitz Roy and Torres del Paine is coincident with the onset of Patagonian glaciations, which would have enhanced erosion and, thus, rock exhumation. An episode of fast rock cooling in the Quaternary is recorded in Torres del Paine rocks, interpreted as enhanced fluvio‐glacial erosion during the Plio‐Pleistocene climate transition toward faster glacial/interglacial cycles. Therefore, we were able to quantify separately the effects of tectonics and climate changes on rock exhumation, what is usually difficult due to simultaneously occurring processes. Mantle upwelling in Southern Patagonia is the most likely mechanism forcing rock exhumation between 10 and 8 Ma in the Fitz Roy massifApatite (U‐Th)/He data reveal glacial erosion as the main driver to the exhumation of the Fitz Roy and Torres del Paine between 7 and 4 MaApatite 4He/3He data reveal intensified fluvio‐glacial erosion in Torres del Paine as a result of the Plio‐Pleistocene climate transition Mantle upwelling in Southern Patagonia is the most likely mechanism forcing rock exhumation between 10 and 8 Ma in the Fitz Roy massif Apatite (U‐Th)/He data reveal glacial erosion as the main driver to the exhumation of the Fitz Roy and Torres del Paine between 7 and 4 Ma Apatite 4He/3He data reveal intensified fluvio‐glacial erosion in Torres del Paine as a result of the Plio‐Pleistocene climate transition

The spatial and temporal distribution of Alpine snow is a sensitive gauge of environmental change. While understanding past snow dynamics is essential for reconstructing past climate and forecasting future trends, reliable snowpack data prior to the instrumental record are scarce. We present a novel pairing of cosmogenic paleothermometry and luminescence photochronometry which constrain the temperature and insolation history of bedrock outcrops at the Gotthard Pass, Switzerland, over the last ∼15,000 years. By coupling these results with cosmogenic 14C‐10Be chronology and modern in situ rock thermometry, we infer a ∼70‐day reduction of snowpack at the topographic mid‐slope. Our data indicate stable environmental conditions throughout the Holocene, followed by a 6.6 ± 2.9°C increase of ground surface temperature, coeval with an order‐of‐magnitude or more increase in ground surface insolation. Bracketing the onset of these changes between 1504 and 1807 CE, our findings tie the snowpack decline with the onset of human industrialization. The extent of snow cover is shrinking in high elevation mountain environments due to climate change. However, it is challenging to determine when snow cover began to change because humans have only been monitoring snow cover for several decades, and snow cover has appeared to shrink over this entire time. We used two new geologic records of ground temperature and light exposure—both of which are impacted by the duration and amount of snow cover—to assess when snow cover began to change in the Gotthard Pass in Switzerland. We found that the middle slopes of the pass began experiencing snow cover loss three centuries ago, well before historical monitoring of snow cover in this region. This record of prolonged snow cover loss matters for the informed management of mountain water sources, rock and snow avalanche risk, and ecosystem change. We present a novel data set of cosmogenic paleothermometry and luminescence photochronometry at the Gotthard Pass, SwitzerlandStable Holocene environmental conditions are followed by increases in ground temperature and insolation caused by snow cover declineThese environmental changes began between 1504 and 1807 CE, tying the observed snowpack decline with the onset of human industrialization We present a novel data set of cosmogenic paleothermometry and luminescence photochronometry at the Gotthard Pass, Switzerland Stable Holocene environmental conditions are followed by increases in ground temperature and insolation caused by snow cover decline These environmental changes began between 1504 and 1807 CE, tying the observed snowpack decline with the onset of human industrialization

The Java Back‐arc Thrust scars the entire back‐arc area of Java Island, but the faults' nature, timing, and activity remain partly elusive. Characterizing the structure and activity of the seismogenic Java Back‐arc Thrust (historical earthquakes up to 7 Mw) is a cornerstone to evaluate associated geohazards. We focus on the western part of Java Back‐arc Thrust that reaches the megalopolis of Jakarta. We combine morphotectonic data, seismic reflection, electric resistivity profiles, kinematic, structural field measurements, paleoseismological trenching, and sediment dating (optically stimulated luminescence and 14C). Our results suggest that the interplay between the faults, volcanoes, and sedimentary basin modulates the propagation of the fault system across and along‐strike. The West Java Back‐arc Thrust has been active from Pliocene to Recent, but with a laterally variable tempo and tectonic regime. While tectonic activity was sustained for longer times in the eastern part, the West Java Back‐arc Thrust broke through the Jakarta Basin in the west, possibly only since the Late Pleistocene, and partitions into a network of immature transpressive structures. We conclude that the West Java Back‐arc Thrust has a high seismic hazard that requires a careful risk evaluation along its trace, as it threatens the numerous infrastructures of the densely populated West Java. Major active, seismogenic back‐arc thrust in northwest JavaThe fault initiated during Pliocene and propagates westwardsIntricate relationships between fault propagation, volcanic activity and foreland sedimentation Major active, seismogenic back‐arc thrust in northwest Java The fault initiated during Pliocene and propagates westwards Intricate relationships between fault propagation, volcanic activity and foreland sedimentation

The main pigments of Brevibacterium linens are the aromatic carotenoids 3,3'-dihydroxyisorenieratene (ϕ,ϕ-carotene-3,3'-diol), the corresponding monohydroxy compound, and the hydrocarbon isorenieratene. We report herein new syntheses of isorenieratene (φ,φ-carotene) and its xanthophyll analogue, 3,3'-dimethoxy-φ,φ-carotene, which may be considered a protected form of the natural xanthophyll, 3,3'-dihydroxy-φ,φ-carotene.

Located at the northern tip of the Altiplano, the Abancay Deflection marks abruptly the latitudinal segmentation of the Central Andes spreading over the Altiplano to the south and the Eastern Cordillera northward. The striking morphological contrast between the low‐relief Altiplano and the high‐relief Eastern Cordillera makes this area a well‐suited place to determine spatiotemporal variations in surface and/or rock uplift and discuss the latest phase of the formation of the Central Andes. Here, we aim to quantify exhumation and uplift patterns in the Abancay Deflection since 40 Ma and present new apatite (U–Th)/He and fission track data from four altitudinal profiles and additional individual samples. Age–elevation relationships and thermal modeling both document that the Abancay Deflection experienced a moderate, spatially uniform, and steady exhumation at 0.2 ± 0.1 km/Myr between 40 and ∼5 Ma implying common large‐scale exhumation mechanism(s). From ∼5 Ma, while the northern part of the Eastern Cordillera and the Altiplano registered similar ongoing slow exhumation, the southern part of the Eastern Cordillera experienced one order‐of‐magnitude of exhumation acceleration (1.2 ± 0.4 km/Myr). This differential exhumation since ∼5 Ma implies active tectonics, river capture, and incision affecting the southern Eastern Cordillera. 3D thermokinematic modeling favors a tectonic decoupling between the Altiplano and the Eastern Cordillera through backthrusting activity of the Apurimac fault. We speculate that the Abancay Deflection, with its “bulls‐eye” structure and significant exhumation rate since 5 Ma, may represent an Andean protosyntaxis, similar to the syntaxes described in the Himalaya or Alaska. Thermochronological data quantifying the tectonic history of the undocumented northern edge of the Peruvian Altiplano (Abancay Deflection)3D thermokinematic models unravel the evolution of the Eastern Cordillera and the AltiplanoSteady and uniform exhumation between 40 and 5 Ma, followed by tectonically driven tilting of the Eastern Cordillera Thermochronological data quantifying the tectonic history of the undocumented northern edge of the Peruvian Altiplano (Abancay Deflection) 3D thermokinematic models unravel the evolution of the Eastern Cordillera and the Altiplano Steady and uniform exhumation between 40 and 5 Ma, followed by tectonically driven tilting of the Eastern Cordillera

The incision history of the Three Rivers (Salween, Mekong, and Yangtze) region in the Southeast Tibetan Plateau has been linked to both tectonic and climatic controls. In this study, we report new apatite (U‐Th)/He and fission‐track thermochronology data from the >6,000‐m‐high Kawagebo massif, which forms the edge of the high plateau on the western flank of the steepened knickzone reach of the middle Mekong River valley. Thermal‐history modeling of a thermochronological age‐elevation profile shows rapid cooling since ~1.5 Ma and suggests a mean Quaternary exhumation rate of >1 km/Myr at the valley bottom. The amount of Quaternary exhumation is too high to be caused by fluvial incision alone and requires additional tectonic uplift. Comparing our data from the western flank of the Mekong River valley with published data from the eastern flank shows differential exhumation across the valley in the late Miocene, with the western flank undergoing more exhumation, but relatively uniform exhumation in the Quaternary. We relate rapid exhumation since the late Miocene on the western flank of the Mekong valley and the high topography of the Kawagebo massif to localized tectonic uplift associated with a restraining (left stepping) overstep between the still‐active right‐lateral Parlung and Zhongdian strike‐slip faults. The pattern of river steepness index across the knickzone also indicates that it results from locally focused uplift. Our results demonstrate the importance of detailed thermochronologic studies in this very active region to constrain the complex multiphase tectonic history before invoking any potential climatic forcing of river incision. New low‐temperature thermochronology data show rapid Quaternary exhumation in the Mekong River knickzone, Southeast TibetBoth the amount of Quaternary exhumation and the pattern of river steepness point to a tectonic origin of the knickzoneThe exhumation history and topography around the knickzone are related to localized tectonic uplift associated with a restraining overstep between the Zhongdian and Parlung faults

Bedrock gorges incising glacial hanging valleys potentially allow measurements of fluvial bedrock incision in mountainous relief. Using digital elevation models, topographic maps, and field reconnaissance, we identified and characterized 30 tributary hanging valleys incised by gorges near their confluence with trunk streams in the Romanche watershed, French Western Alps. Longitudinal profiles of these tributaries are all convex and have abrupt knickpoints at the upper limit of oversteepened gorge reaches. We reconstructed initial glacial profiles from glacially polished bedrock knobs surrounding the gorges in order to quantify the amount of fluvial incision and knickpoint retreat. From morphometric analyses, we find that mean channel gradients and widths, as well as knickpoint retreat rates, display a drainage area dependence modulated by bedrock lithology. However, there appears to be no relation between horizontal retreat and vertical downwearing of knickpoints. Assuming a postglacial origin of these gorges, our results imply high postglacial fluvial incision (0.5–15 mm yr−1) and knickpoint retreat (1–200 mm yr−1) rates that are, however, consistent with previous estimates. Numerical modeling was used to test the capacity of different fluvial incision models to predict the inferred evolution of the gorges. Results from simple end‐member models suggest transport‐limited behavior of the bedrock gorges. A more sophisticated model including dynamic width adjustment and sediment‐dependent incision rates predicts present‐day channel geometry only if a significant supply of sediment from the gorge sidewalls (∼10 mm yr−1) is triggered by gorge deepening, combined with pronounced inhibition of bedrock incision by sediment transport and deposition.

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