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Cosmogenic 10^Be and 26^Al concentrations in fluvial sediments from the Mohand Range in the northwestern Himalaya

Because of the multi-stepped pathways of sediment comprising the foreland fold-thrust belt (FFTB), detrital quartz grains that recycle from the FFTB sources contain cosmogenic radionuclides (CRN), such as 10^Be and 26^Al, accumulated during previous exposure, resulting in inheritance and, hence, anomalously low erosion rates. This inhibits the straightforward use of 10^Be as tracers for modern erosion rates and sediment discharge from the FFTB, prevalent at the external edges of collisional orogens such as the Himalaya. We present a novel approach for quantifying the erosion rates of FFTB by comparing measured and modeled CRN concentrations in fluvial sediments. We apply this approach to the Mohand Range, an emergent fault-related fold in the frontal part of the northwestern Himalaya (see the location map below). The 10^Be and 26^Al datasets presented here were used to calibrate our model, which we used to quantify the erosion rates in and sediment flux from the Mohand Range. Datasets provided here include a summary of the location and depositional age of 33 fluvial sediments and two sandstone samples collected from the Mohand Range, 10^Be analysis results of 23 of these fluvial sediments and two bedrock samples, and 26^Al-10^Be pair analysis results of the remaining ten fluvial sediment samples (Dataset S1). Moreover, the data include the depositional age map of uplifted older foreland sediments across the western Mohand Range (Dataset 2) and the map of best-fit 10^Be concentration inherited from Himalayan paleoerosion (Dataset 3) and sediment burial in the foreland (Dataset 4). We also include a map of the best-fit 10^Be concentration produced during modern erosion of the Mohand Range (Dataset 5) and a map of the best-fit uplift/erosion rates across the western Mohand Range (Dataset 6). For more information (e.g., sampling method, analytical procedure, and data processing), please refer to the main article (Mandal et al., 2023).

Seismic data from the Hochvogel summit array

Large rock slope failures play a pivotal role in long-term landscape evolution and are a major concern in land use planning and hazard aspects. While the failure phase and the time immediately prior to failure are increasingly well studied, the nature of the preparation phase remains enigmatic. This knowledge gap is due, to a large degree, to difficulties associated with instrumenting high mountain terrain and the local nature of classic monitoring methods, which does not allow integral observation of large rock volumes. Here, we analyse data from a small network of up to seven seismic sensors installed during July--October 2018 (with 43 days of data loss) at the summit of the Hochvogel, a 2592 m high Alpine peak. We develop proxy time series indicative of cyclic and progressive changes of the summit. Fundamental frequency analysis, horizontal-to-vertical spectral ratio data and end-member modelling analysis reveal diurnal cycles of increasing and decreasing coupling stiffness of a 126,000 m^3 large, instable rock volume, due to thermal forcing. Relative seismic wave velocity changes also indicate diurnal accumulation and release of stress within the rock mass. At longer time scales, there is a systematic superimposed pattern of stress increases over multiple days and episodic stress release within a few days, expressed in an increased emission of short seismic pulses indicative of rock cracking. We interpret our data to reflect an early stage of stick slip motion of a large rock mass, providing new information on the development of large-scale slope instabilities towards catastrophic failure.

ESD_thermotrace, A new software to interpret tracer thermochronometry datasets and quantify related confidence levels

We present a new Python-based Jupyter Notebook that helps interpreting detrital tracer thermochronometry datasets and quantifying the statistical confidence of such analysis. Users are referred to the linked GitHub repository for usage and methods. https://github.com/mdlndr/ESD_thermotrace

river-clusters: Clustering river profiles from topographic data

This software package contains code for performing agglomerative hierarchical clustering on river long profiles extracted from topographic data. The software requires initial topographic analysis to extract river profiles based on the Edinburgh Land Surface Topographic Tools package. Detailed documentation and tutorials for installation and running the code can be found at https://lsdtopotools.github.io/LSDTT_documentation/. The package written in Python and based on the scipy cluster package. The development version of the code can be found on GitHub (https://github.com/UP-RS-ESP/river-clusters) along with full instructions on how to install and run the code.

AFG - Active Faults Greece: a comprehensive geomorphology-based 1:25,000 fault database

Greece is Europe’s most seismically active nation, as it is being deformed by an active subduction system and one of the world’s fastest-spreading rifts. Onshore active faults pose seismic hazard that cannot be reliably assessed in the absence of a comprehensive map of potential earthquake sources. Here, we use high-resolution Digital Elevation Models (DEMs), in conjunction with hillshades and slope models, to map and characterise faults in Greece at a scale of 1:25000. The Active Faults Greece (AFG) database records a total of 3815 fault-traces assigned to 892 interpreted faults. Of the AFG traces, 53% were mapped here for the first time, with their geometries and slip-sense constrained by displacement of landscape features. AFG includes >2000 active and 1632 probably active fault-traces, while 30 traces result from historic surface-rupturing earthquakes since 464 BC. About 57% of faults exhibit strong depositional control (DC) on sedimentation patterns, with active faults being characterised by approximately equal numbers of sharp (32%), moderate (29%) and rounded (29%) scarps. AFG is the first fault database in Greece generated using nationwide interpretation of geomorphology and has applications in paleoseismology, seismic-hazard assessment, mineral-resources exploration, and resilience planning. Data Access: - Download archive version via GFZ Data Services (upper left) - Web-Map Server: https://experience.arcgis.com/experience/a6c85b1edf9d4d17a3f01a70cef6d2b2 - GIS Users: https://services2.arcgis.com/T7iULq65Kp9Elquk/arcgis/rest/services/Active_Faults_Greece/FeatureServer - Layerfiles for use in ArcGIS Pro and QGIS: https://noaig.maps.arcgis.com/sharing/rest/content/items/4b93c25b931744dabc4851abf9c8ae38/data

Drilling Overdeepened Alpine Valleys (DOVE) - Operational Dataset of DOVE Phase 1

The overarching goal of the Drilling Overdeepened Alpine Valleys (DOVE) project will be to date the age and extent of past glaciations. Formerly-glaciated areas are often characterized by deeply incised structures, often filled by Quaternary deposits. These buried troughs and valleys were formed by glacial overdeepening, likely caused by pressurized subglacial meltwater below warm-based glaciers. Results of this drilling campaign, supported by new dating technologies, will further provide critical data on 'how' and 'at which rate' glacial erosion affects such mountain ranges and their foreland. These processes are also of fundamental importance for evaluating the safety of radioactive waste disposal sites, which are planned in areas of former glaciations. Moreover, results of this project will fill gaps in the knowledge of paleoclimate and atmospheric circulation patterns during past glacial epochs and how these patterns affected ice build-up. The operational data sets include the drill core documentation from the mobile Drilling Information System (mDIS), full round core scans, MSCL data sets, a preliminary core description and the geophysical downhole logging data that were acquired during and subsequent to the drilling operations. All downhole logs and core depth were subject to depth correction to a common depth master (cf. operational report for detailed information). The data are described by two scientific reports, the Operational Report (https://doi.org/10.48440/ICDP.5068.001) and the Explanatory Remarks on the Operational Datasets (https://doi.org/10.48440/ICDP.5068.002).

Fault database of the Northern Chile forearc between 18°50’S and 19°45’S

The knowledge about the distribution of active faults is crucial for hazard assessment (Costa et al., 2020; Santibáñez et al., 2019; Wesnousky, 1986) but also provides insights into tectonic control on hydrological processes (Binnie et al., 2020; Jeffery et al., 2013; Pan et al., 2013) or georesource distribution (Goldsworthy & Jackson, 2000; Viguier et al., 2018). Furthermore, tectonically driven topographic uplift and its impact on climate (Armijo et al., 2015; Houston & Hartley, 2003; Rech et al., 2019; Zhisheng et al., 2001) can be better understood if a systematically mapped fault database exists. Here we present an active fault database, as well as the distribution of drainages, for an area between 18.50°S and 19.45°S in Northern Chile forearc, which were systematically mapped in the framework of the project “Cluster C05-Tectonic Geomorphology: Adaptation of drainage to tectonic forcing” of the CRC1211- Earth Evolution at the Dry Limit. The Central Andes forearc at this latitude is located at a highly tectonically active convergent margin and hosts major earthquakes not only on the plate boundary itself (e.g., Métois et al., 2016), but also in the overriding crust (e.g., Comte et al., 1999). It comprises, from west to east, the Coastal Cordillera, Longitudinal Valley and the Western Flank of the Altiplano, showing an impressive amount of topographic variability of ca. 4000 m. Nevertheless, Neogene crustal tectonic structures and surface deformation are poorly documented. The overall landscape appears as a gentle west-sloping pediplain dissected by deep transversal canyons (quebradas), which reach the current Pacific Ocean (Mortimer, 1980). The Longitudinal Valley is a sedimentary basin filled with 432 to 2000 m of Tertiary to Quaternary deposits derived from the Altiplano in the east as well as the Coastal Cordillera in the west (García et al., 2017). Its surface is composed by a multiphase planation surface called the Pacific Paleosurface (PPS), which distribution is suggested to be controlled by crustal tectonics (Evenstar et al., 2017). Depending on the low ratio of tectonic displacement rate to sedimentation rate, many active faults are hidden and only a specialized approach of high-resolution fault mapping, together with a morphometric analysis of the drainage pattern provides systematic information about the distribution of active faults, folds and related structures. The present fault database is the result of creating a comprehensive catalogue of faults classified by the age of last proven/probable tectonic activity. This is accompanied by a compilation of existing age data and a map of drainage pattern. These datasets were compiled in QGIS 3.16.5 (https://www.qgis.org) and are available as. gpkg for GIS applications and as .kml formats to be visualized in Google Earth.

EMMAgeo - R package

EMMA – End Member Modelling Analysis of grain-size data is a technique to unmix multimodal grain-size data sets, i.e., to decompose the data into the underlying grain-size distributions (loadings) and their contributions to each sample (scores). The R package EMMAgeo contains a series of functions to perform EMMA based on eigenspace decomposition. The data are rescaled and transformed to receive results in meaningful units, i.e., volume percentage. EMMA can be performed in a deterministic and two robust ways, the latter taking into account incomplete knowledge about model parameters. The model outputs can be interpreted in terms of sediment sources, transport pathways and transport regimes (loadings) as well as their relative importance throughout the sample space (scores).

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