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Fold-and-thrust belts are structural features that accommodate upper-crustal shortening by the growth of a series of thrust faults and folds. Recent studies show that a better understanding of the structure and sedimentation styles of fold-and-thrust belts and their associated basins can provide crucial insights for improved interpretations of the evolution of ancient and modern convergent margins and the mechanisms of intracontinental deformation. To achieve a more comprehensive understanding of the development of contractional orogenic belts, this thematic collection gathers contributions that explore different types of fold-and-thrust belts at various scales around the world, via different approaches including theory development, structural and stratigraphic observations from the field, geophysical analyses, and numerical modelling. Case studies include the northern margin of the Tibetan plateau and Pamir region, the Timanian and Caledonian orogenies in northern Norway, orogenic belts in western Laurentia, and the Andes of western South America. These studies reemphasize the importance of integrating broad datasets when documenting the distribution, geometry, and kinematics of structures in fold-and-thrust belts and their associated basins, including field-based structural observations, provenance, low-temperature thermochronologic, geomorphologic, and subsurface data, and analog and numerical models. This thematic collection aims to encourage further efforts for comparative studies of the fold-and-thrust belts around the world and proposes interdisciplinary research to address outstanding questions in the study of contractional orogens. Thematic collection: This article is part of the Fold-and-thrust belts collection available at: https://www.lyellcollection.org/topic/collections/fold-and-thrust-belts-and-associated-basins 

Abstract During the past few years, distributed acoustic sensing (DAS) has become an invaluable tool for recording high-fidelity seismic wavefields with great spatiotemporal resolutions. However, the considerable amount of data generated during DAS experiments limits their distribution with the broader scientific community. Such a bottleneck inherently slows down the pursuit of new scientific discoveries in geosciences. Here, we introduce PubDAS—the first large-scale open-source repository where several DAS datasets from multiple experiments are publicly shared. PubDAS currently hosts eight datasets covering a variety of geological settings (e.g., urban centers, underground mines, and seafloor), spanning from several days to several years, offering both continuous and triggered active source recordings, and totaling up to ∼90 TB of data. This article describes these datasets, their metadata, and how to access and download them. Some of these datasets have only been shallowly explored, leaving the door open for new discoveries in Earth sciences and beyond. 

Abstract Estimates of the permafrost-climate feedback vary in magnitude and sign, partly because permafrost carbon stability in warmer-than-present conditions is not well constrained. Here we use a Plio-Pleistocene lacustrine reconstruction of mean annual air temperature (MAAT) from the Tibetan Plateau, the largest alpine permafrost region on the Earth, to constrain past and future changes in permafrost carbon storage. Clumped isotope-temperatures (Δ 47 -T) indicate warmer MAAT (~1.2 °C) prior to 2.7 Ma, and support a permafrost-free environment on the northern Tibetan Plateau in a warmer-than-present climate. Δ 47 -T indicate ~8.1 °C cooling from 2.7 Ma, coincident with Northern Hemisphere glacial intensification. Combined with climate models and global permafrost distribution, these results indicate, under conditions similar to mid-Pliocene Warm period (3.3–3.0 Ma), ~60% of alpine permafrost containing ~85 petagrams of carbon may be vulnerable to thawing compared to ~20% of circumarctic permafrost. This estimate highlights ~25% of permafrost carbon and the permafrost-climate feedback could originate in alpine areas. 

Existing models of intracontinental deformation have focused on plate-like rigid body motion v. viscous-flow-like distributed deformation. To elucidate how plate convergence is accommodated by intracontinental strike-slip faulting and block rotation within a fold–thrust belt, we examine the Cenozoic structural framework of the central Qilian Shan of northeastern Tibet, where the NW-striking, right-slip Elashan and Riyueshan faults terminate at the WNW-striking, left-slip Haiyuan and Kunlun faults. Field- and satellite-based observations of discrete right-slip fault segments, releasing bends, horsetail termination splays and off-fault normal faulting suggest that the right-slip faults accommodate block rotation and distributed west–east crustal stretching between the Haiyuan and Kunlun faults. Luminescence dating of offset terrace risers along the Riyueshan fault yields a Quaternary slip rate of c. 1.1 mm a −1 , which is similar to previous estimates. By integrating our results with regional deformation constraints, we propose that the pattern of Cenozoic deformation in northeastern Tibet is compatible with west–east crustal stretching/lateral displacement, non-rigid off-fault deformation and broad clockwise rotation and bookshelf faulting, which together accommodate NE–SW India–Asia convergence. In this model, the faults represent strain localization that approximates continuum deformation during regional clockwise lithospheric flow against the rigid Eurasian continent. Supplementary material: Luminescence dating procedures and protocols is available at https://doi.org/10.17605/OSF.IO/CR9MN Thematic collection: This article is part of the Fold-and-thrust belts and associated basins collection available at: https://www.lyellcollection.org/cc/fold-and-thrust-belts