TY - JOUR A1 - Dahm, Torsten A1 - Hainzl, Sebastian T1 - A Coulomb stress response model for time-dependent earthquake forecasts JF - Journal of geophysical research : Solid earth N2 - Seismicity models are probabilistic forecasts of earthquake rates to support seismic hazard assessment. Physics-based models allow extrapolating previously unsampled parameter ranges and enable conclusions on underlying tectonic or human-induced processes. The Coulomb Failure (CF) and the rate-and-state (RS) models are two widely used physics-based seismicity models both assuming pre-existing populations of faults responding to Coulomb stress changes. The CF model depends on the absolute Coulomb stress and assumes instantaneous triggering if stress exceeds a threshold, while the RS model only depends on stress changes. Both models can predict background earthquake rates and time-dependent stress effects, but the RS model with its three independent parameters can additionally explain delayed aftershock triggering. This study introduces a modified CF model where the instantaneous triggering is replaced by a mean time-to-failure depending on the absolute stress value. For the specific choice of an exponential dependence on stress and a stationary initial seismicity rate, we show that the model leads to identical results as the RS model and reproduces the Omori-Utsu relation for aftershock decays as well stress-shadowing effects. Thus, both CF and RS models can be seen as special cases of the new model. However, the new stress response model can also account for subcritical initial stress conditions and alternative functions of the mean time-to-failure depending on the problem and fracture mode. KW - seismicity KW - physics based model KW - earthquake physics Y1 - 2022 U6 - https://doi.org/10.1029/2022JB024443 SN - 2169-9313 SN - 2169-9356 VL - 127 IS - 9 PB - American Geophysical Union CY - Washington ER - TY - JOUR A1 - Sieber, Melanie J. A1 - Wilke, Max A1 - Appelt, Oona A1 - Oelze, Marcus A1 - Koch-Müller, Monika T1 - Melting relations of Ca-Mg carbonates and trace element signature of carbonate melts up to 9 GPa - a proxy for melting of carbonated mantle lithologies JF - European journal of mineralogy N2 - The most profound consequences of the presence of Ca-Mg carbonates (CaCO3-MgCO3) in the Earth's upper mantle may be to lower the melting temperatures of the mantle and control the melt composition. Low-degree partial melting of a carbonate-bearing mantle produces CO2-rich, silica-poor melts compositionally imposed by the melting relations of carbonates. Thus, understanding the melting relations in the CaCO3-MgCO3 system facilitates the interpretation of natural carbonate-bearing silicate systems. We report the melting relations of the CaCO3-MgCO3 system and the partition coefficient of trace elements between carbonates and carbonate melt from experiments at high pressure (6 and 9 GPa) and temperature (1300-1800 degrees C) using a rocking multi-anvil press. In the absence of water, Ca-Mg carbonates are stable along geothermal gradients typical of subducting slabs. Ca-Mg carbonates ( similar to Mg0.1-0.9Ca0.9-0.1CO3) partially melt beneath mid-ocean ridges and in plume settings. Ca-Mg carbonates melt incongruently, forming periclase crystals and carbonate melt between 4 and 9 GPa. Furthermore, we show that the rare earth element (REE) signature of Group-I kimberlites, namely strong REE fractionation and depletion of heavy REE relative to the primitive mantle, is resembled by carbonate melt in equilibrium with Ca-bearing magnesite and periclase at 6 and 9 GPa. This suggests that the dolomite-magnesite join of the CaCO3-MgCO3 system might be useful to approximate the REE signature of carbonate-rich melts parental to kimberlites. Y1 - 2022 U6 - https://doi.org/10.5194/ejm-34-411-2022 SN - 0935-1221 SN - 1617-4011 VL - 34 IS - 5 SP - 411 EP - 424 PB - Copernicus CY - Göttingen ER - TY - JOUR A1 - Jia, Zeyu A1 - Lipus, Daniel A1 - Bartholomaeus, Alexander A1 - Burckhardt, Oliver A1 - Sondermann, Megan A1 - Wagner, Dirk A1 - Kallmeyer, Jens T1 - Metagenome-assembled genome of a putative methanogenic Methanosarcina sp. strain enriched from terrestrial high-CO2 subsurface sediments JF - Microbiology Resource Announcements N2 - A metagenome-assembled genome (MAG), named Methanosarcina sp. strain ERenArc_MAG2, was obtained from a 3-month-old H-2/CO2 atmosphere enrichment culture, originally inoculated with 60-m deep drill core sediment collected from the tectonic Eger Rift terrestrial subsurface. Annotation of the recovered draft genome revealed putative archaeal methanogenesis genes in the deep biosphere. A metagenome-assembled genome (MAG), named Methanosarcina sp. strain ERenArc_MAG2, was obtained from a 3-month-old H-2/CO2 atmosphere enrichment culture, originally inoculated with 60-m deep drill core sediment collected from the tectonic Eger Rift terrestrial subsurface. Annotation of the recovered draft genome revealed putative archaeal methanogenesis genes in the deep biosphere. Y1 - 2022 U6 - https://doi.org/10.1128/mra.01039-22 SN - 2576-098X VL - 11 IS - 12 PB - American Society for Microbiology CY - Washington ER - TY - JOUR A1 - Lück, Erika A1 - Guillemoteau, Julien A1 - Tronicke, Jens A1 - Rummel, Udo A1 - Hierold, Wilfried T1 - From point to field scale-indirect monitoring of soil moisture variations at the DWD test site in Falkenberg JF - Geoderma : an international journal of soil science N2 - Information regarding the spatial distribution of soil water content is key in many disciplines and applications including soil and atmospheric sciences, hydrology, and agricultural engineering. Thus, within the past decades various experimental methods and strategies have been developed to map spatial variations in soil moisture distribution and to monitor temporal changes. Our study examines the combination of electrical resistivity mapping and point observations of soil moisture to infer the spatial and the temporal variability of soil moisture. Over a period of around two years, we performed field measurements on six days to collect repeated electrical resistivity mapping data for a nine-hectare test site south-east of Berlin, Germany. Permanently installed TDR probes, temporary TDR measurements within permanently installed tubes, and gravimetric measurements using soil samples provided soil moisture data at various selected points. In addition, soil analysis and classification results are available for 132 regularly distributed positions up to depths of 1.2 m. We compare and link three-dimensional resistivity models obtained via data inversion to soil composition and soil moisture as provided by our point data. Both the soil samples and the resistivity models indicate a two-layer medium characterized by a sandy top layer with varying thickness and a loamy bottom soil. For all six field campaigns, we observe similar resistivity patterns reflecting the temporally stable influence of soil texture. While the overall patterns are stable, the range of resistivity values changes with soil moisture. Finally, to estimate spatial models of soil moisture, we link our soil moisture and resistivity data using empirical petrophysical models relying on a second order polynomial function. We observe a mean prediction error for soil moisture of +/-0.034 m3 & BULL; m? 3 using all observation points while we notice that point-specific models further reduce the error. Thus, we conclude that our experimental and data analysis strategies represent a reliable approach to establish site-specific models and to estimate three-dimensional moisture distribution including temporal variations. KW - earth boundary layer KW - electrical conductivity KW - electrical resistivity KW - near-surface geophysics KW - soil moisture at field scale Y1 - 2022 U6 - https://doi.org/10.1016/j.geoderma.2022.116134 SN - 0016-7061 SN - 1872-6259 VL - 427 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Scherbaum, Frank A1 - Mzhavanadze, Nana A1 - Rosenzweig, Sebastian A1 - Müller, Meinard T1 - Tuning systems of traditional Georgian singing determined from a new corpus of field recordings JF - Musicologist N2 - In this study we examine the tonal organization of the 2016 GVM dataset, a newly-created corpus of high-quality multimedia field recordings of traditional Georgian singing with a focus on Svaneti. For this purpose, we developed a new processing pipeline for the computational analysis of non-western polyphonic music which was subsequently applied to the complete 2016 GVM dataset. To evaluate under what conditions a single tuning system is representative of current Svan performance practice, we examined the stability of the obtained tuning systems from an ensemble-, a song-, and a corpus-related perspective. Furthermore, we compared the resulting Svan tuning systems with the tuning systems obtained for the Erkomaishvili dataset (Rosenzweig et al., 2020) in the study by Scherbaum et al. (2020). In comparison to a 12-TET (12-tone-equal-temperament) system, the Erkomaishvili and the Svan tuning systems are surprisingly similar. Both systems show a strong presence of pure fourths (500 cents) and fifths (700 cents), and 'neutral' thirds (peaking around 350 cents) as well as 'neutral' sixths. In addition, the sizes of the melodic and the harmonic seconds in both tuning systems differ systematically from each other, with the size of the harmonic second being systematically larger than the melodic one. KW - traditional Georgian music KW - tuning KW - computational ethnomusicology Y1 - 2022 U6 - https://doi.org/10.33906/musicologist.1068947 SN - 2618-5652 VL - 6 IS - 2 SP - 142 EP - 168 PB - Trabzon Univ State Conservatory CY - Trabzon ER - TY - JOUR A1 - Bannister, Stephen A1 - Bertrand, Edward A. A1 - Heimann, Sebastian A1 - Bourguignon, Sandra A1 - Asher, Cameron A1 - Shanks, Jackson A1 - Harvison, Adrian T1 - Imaging sub-caldera structure with local seismicity, Okataina Volcanic Centre, Taupo Volcanic Zone, using double-difference seismic tomography JF - Journal of volcanology and geothermal research N2 - We examine sub-caldera structure and seismicity in and around the Okataina Volcanic Centre (OVC), Taupo Volcanic Zone, New Zealand, using seismic data collected over 4+ years with a temporary array of broadband and short-period seismometers, supplementing data from the permanent New Zealand seismometer network. We derive a new 3-D image of P-wave seismic velocity for the upper crust in the region, using double-difference seismic tomography and utilising waveform cross-correlations. We subsequently relocate 6989 earthquakes which occurred in the region over the 2010-2021 time period, using the 3D velocity model. The seismicity distribution shows spatial clusters west of Lake Rotomahana, as well as beneath Haroharo and the Makatiti Dome, inside the Okataina caldera. Beneath Makatiti Dome 90% of the events are shallower than 7.7 +/- 0.5 km. Outside of the Okataina caldera event relocations highlight short (similar to 3-4 km long) streaks of activity in the Ngakuru graben, part of the active Taupo Rift southwest of Okataina caldera. Inside the OVC the relocated seismicity beneath Makatiti appears closely associated with low (similar to 10%) P-wave velocity anomalies, which we resolve in the similar to 5-to-8-km depth range beneath the Okataina caldera, and which are likely related to partial melt and/or fluid-volatile pathways. Moment tensor analyses for two larger-magnitude events (M(L)4.5 and M(L)4.9) near Haroharo indicate normal faulting, with NNE-SSW fault strike, but with positive CLVD and positive isotropic components when allowing for a full moment tensor, consistent with a magmatic environment with degassing and/or fluid migration. KW - Okataina Caldera KW - Taupo Rift KW - seismic tomography KW - sub-caldera structure KW - Volcanic system Y1 - 2022 U6 - https://doi.org/10.1016/j.jvolgeores.2022.107653 SN - 0377-0273 SN - 1872-6097 VL - 431 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kothari, Kritika A1 - Battisti, Rafael A1 - Boote, Kenneth J. A1 - Archontoulis, Sotirios A1 - Confalone, Adriana A1 - Constantin, Julie A1 - Cuadra, Santiago A1 - Debaeke, Philippe A1 - Faye, Babacar A1 - Grant, Brian A1 - Hoogenboom, Gerrit A1 - Jing, Qi A1 - van der Laan, Michael A1 - Macena da Silva, Fernando Antonio A1 - Marin, Fabio R. A1 - Nehbandani, Alireza A1 - Nendel, Claas A1 - Purcell, Larry C. A1 - Qian, Budong A1 - Ruane, Alex C. A1 - Schoving, Celine A1 - Silva, Evandro H. F. M. A1 - Smith, Ward A1 - Soltani, Afshin A1 - Srivastava, Amit A1 - Vieira, Nilson A. A1 - Slone, Stacey A1 - Salmeron, Montserrat T1 - Are soybean models ready for climate change food impact assessments? JF - European journal of agronomy : the official journal of the European Society for Agronomy N2 - An accurate estimation of crop yield under climate change scenarios is essential to quantify our ability to feed a growing population and develop agronomic adaptations to meet future food demand. A coordinated evaluation of yield simulations from process-based eco-physiological models for climate change impact assessment is still missing for soybean, the most widely grown grain legume and the main source of protein in our food chain. In this first soybean multi-model study, we used ten prominent models capable of simulating soybean yield under varying temperature and atmospheric CO2 concentration [CO2] to quantify the uncertainty in soybean yield simulations in response to these factors. Models were first parametrized with high quality measured data from five contrasting environments. We found considerable variability among models in simulated yield responses to increasing temperature and [CO2]. For example, under a + 3 degrees C temperature rise in our coolest location in Argentina, some models simulated that yield would reduce as much as 24%, while others simulated yield increases up to 29%. In our warmest location in Brazil, the models simulated a yield reduction ranging from a 38% decrease under + 3 degrees C temperature rise to no effect on yield. Similarly, when increasing [CO2] from 360 to 540 ppm, the models simulated a yield increase that ranged from 6% to 31%. Model calibration did not reduce variability across models but had an unexpected effect on modifying yield responses to temperature for some of the models. The high uncertainty in model responses indicates the limited applicability of individual models for climate change food projections. However, the ensemble mean of simulations across models was an effective tool to reduce the high uncertainty in soybean yield simulations associated with individual models and their parametrization. Ensemble mean yield responses to temperature and [CO2] were similar to those reported from the literature. Our study is the first demonstration of the benefits achieved from using an ensemble of grain legume models for climate change food projections, and highlights that further soybean model development with experiments under elevated [CO2] and temperature is needed to reduce the uncertainty from the individual models. KW - Agricultural Model Inter-comparison and Improvement Project (AgMIP); KW - Model ensemble KW - Model calibration KW - Temperature KW - Atmospheric CO2 KW - concentration KW - Legume model Y1 - 2022 U6 - https://doi.org/10.1016/j.eja.2022.126482 SN - 1161-0301 SN - 1873-7331 VL - 135 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Rajewar, S. K. A1 - Mohana Lakshmi, Ch. A1 - Mohanty, Aditya A1 - Pandey, Dwijendra N. A1 - Pandey, Anshuman A1 - Chaurasia, Anurag A1 - Pandey, Ananya A1 - Rajeswar Rao, V. A1 - Naidu, M. S. A1 - Kumar, Amit A1 - Mondal, Saroj K. A1 - Yadav, Rajeev K. A1 - Catherine, J. K. A1 - Giri, R. K. A1 - Gahalaut, Vineet Kumar T1 - Constraining plate motion and crustal deformation from GNSS measurements BT - CSIR-NGRI contribution JF - Journal of the Geological Society of India N2 - Geodetic studies of crustal deformation using Global Navigation Satellite System (GNSS, earlier commonly referred to as Global Positioning System, GPS) measurements at CSIR-NGRI started in 1995 with the installation of a permanent GNSS station at CSIR-NGRI Hyderabad which later became an International GNSS Service (IGS) site. The CSIR-NGRI started expanding its GNSS networks after 2003 with more focussed studies through installation in the NE India, Himalayan arc, Andaman subduction zone, stable and failed rift regions of India plate. In each instance, these measurements helped in unravelling the geodynamics of the region and seismic hazard assessment, e.g., the discovery of a plate boundary fault in the Indo-Burmese wedge, rate and mode of strain accumulation and its spatial variation in the Garhwal-Kumaun and Kashmir region of the Himalayan arc, the influence of non-tectonic deformation on tectonic deformation in the Himalayan arc, nature of crustal deformation through earthquake cycle in the Andaman Sumatra subduction zone, and localised deformation in the intraplate region and across the paleo rift regions. Besides these, GNSS measurements initiated in the Antarctica region have helped in understanding the plate motion and influence of seasonal variations on deformation. Another important by-product of the GNSS observations is the capabilities of these observations in understanding the ionospheric variations due to earthquake processes and also due to solar eclipse. We summarize these outcomes in this article. Y1 - 2021 U6 - https://doi.org/10.1007/s12594-021-1850-8 SN - 0974-6889 VL - 97 IS - 10 SP - 1207 EP - 1213 PB - Springer India CY - New Delhi ER - TY - JOUR A1 - Płóciennik, Mateusz A1 - Zawiska, Izabela A1 - Rzodkiewicz, Monika A1 - Noryśkiewicz, Agnieszka M. A1 - Słowiński, Michał A1 - Müller, Daniela A1 - Brauer, Achim A1 - Antczak-Orlewska, Olga A1 - Kramkowski, Mateusz A1 - Peyron, Odile A1 - Nevalainen, Liisa A1 - Luoto, Tomi P. A1 - Kotrys, Bartosz A1 - Seppä, Heikki A1 - Bidaurreta, Jon Camuera A1 - Rudna, Marta A1 - Mielczarek, Małgorzata A1 - Zawisza, Edyta A1 - Janowska, Ewa A1 - Błaszkiewicz, Mirosław T1 - Climatic and hydrological variability as a driver of the Lake Gościąż biota during the Younger Dryas JF - Catena N2 - The Younger Dryas (YD) is a roughly 1,100-year cold period marking the end of the last glaciation. Climate modelling for northern Europe indicates high summer temperatures and strong continentality. In eastern Europe, the scale of temperature variation and its influence on ecosystems is weakly recognised. Here, we present a multi-proxy reconstruction of YD conditions from Lake Gos ' ciaz (central Poland). The decadal-resolution analysis of its annually varved sediments indicates an initial decrease in Chironomidae-inferred mean July air temperature followed by steady warming. The pollen-inferred winter-to-summer temperature amplitude and annual precip-itation is highest at the Allerod/YD transition and the early YD (ca. 12.7-12.4 ky cal BP) and YD/Holocene (11.7-11.4 ka cal BP) transition. Temperature and precipitation were the main reasons for lake level fluctuations as reflected in the planktonic/littoral Cladocera ratio. The lake's diatom-inferred total phosphorus decreased with increasing summer temperature from about mid YD. Windy conditions in the early YD until ~12.3 ka cal BP caused water mixing and a short-lived/temporary increase in nutrient availability for phytoplankton. The Chironomidae-inferred summer temperature and pollen inferred summer temperature, winter temperature and annual precipitation herein are one of only a few in eastern Europe conducted with such high resolution. KW - Late Glacial KW - Varved sediments KW - Climate reconstructions KW - Chironomidae KW - Cladocera KW - Pollen KW - Diatoms Y1 - 2022 U6 - https://doi.org/10.1016/j.catena.2022.106049 SN - 0341-8162 SN - 1872-6887 VL - 212 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Lupien, Rachel L. A1 - Russell, James M. A1 - Pearson, Emma J. A1 - Castaneda, Isla S. A1 - Asrat, Asfawossen A1 - Förster, Verena A1 - Lamb, Henry F. A1 - Roberts, Helen M. A1 - Schäbitz, Frank A1 - Trauth, Martin H. A1 - Beck, Catherine C. A1 - Feibel, Craig S. A1 - Cohen, Andrew S. T1 - Orbital controls on eastern African hydroclimate in the Pleistocene JF - Scientific reports N2 - Understanding eastern African paleoclimate is critical for contextualizing early human evolution, adaptation, and dispersal, yet Pleistocene climate of this region and its governing mechanisms remain poorly understood due to the lack of long, orbitally-resolved, terrestrial paleoclimate records. Here we present leaf wax hydrogen isotope records of rainfall from paleolake sediment cores from key time windows that resolve long-term trends, variations, and high-latitude effects on tropical African precipitation. Eastern African rainfall was dominantly controlled by variations in low-latitude summer insolation during most of the early and middle Pleistocene, with little evidence that glacial-interglacial cycles impacted rainfall until the late Pleistocene. We observe the influence of high-latitude-driven climate processes emerging from the last interglacial (Marine Isotope Stage 5) to the present, an interval when glacial-interglacial cycles were strong and insolation forcing was weak. Our results demonstrate a variable response of eastern African rainfall to low-latitude insolation forcing and high-latitude-driven climate change, likely related to the relative strengths of these forcings through time and a threshold in monsoon sensitivity. We observe little difference in mean rainfall between the early, middle, and late Pleistocene, which suggests that orbitally-driven climate variations likely played a more significant role than gradual change in the relationship between early humans and their environment. Y1 - 2022 U6 - https://doi.org/10.1038/s41598-022-06826-z SN - 2045-2322 VL - 12 IS - 1 PB - Macmillan Publishers Limited CY - London ER -