154 documents found in 387ms
# 1
Dobslaw, Henryk • Dill, Robert • Zhang, Liangjing • Boergens, Eva
Abstract: GRACE/GRACE-FO Level-3 product representing Ocean Bottom Pressure (OBP) variations provided at 1° latitude-longitude grids as defined over ocean areas. The OBP grids are provided in NetCDF format divided into yearly batches. The files each contain eight different variables: 1) 'barslv': gravity-based barystatic sea-level pressure2) 'error_barslv': gravity-based barystatic sea-level pressure uncertainties3) 'resobp': gravity-based residual ocean circulation pressure resobp4) 'error_resobp': gravity-based residual ocean circulation pressure uncertainties5) 'leakage': apparent gravity-based bottom pressure due to continental leakage leakage6) 'error_leakage': apparent gravity-based bottom pressure due to continental leakage uncertainties7) 'model_ocean': background-model ocean circulation pressure8) 'model_atmosphere': background-model atmospheric surface pressure These Level-3 products are visualized at GFZ's web portal GravIS (http://gravis.gfz-potsdam.de). Link to data products: ftp://isdcftp.gfz-potsdam.de/grace/GravIS/GFZ/Level-3/OBP
# 2
Zhang, Liangjing • Dobslaw, Henryk • Dill, Robert • Boergens, Eva
Abstract: GRACE/GRACE-FO Level-3 product representing Terrestrial Water Storage (TWS) anomalies provided at 1° latitude-longitude grids as defined over all non-glaciated continental regions. The TWS anomaly grids are provided in NetCDF format divided into yearly batches. The files each contain three different variables: 1) 'tws': gravity-based TWS2) 'error_tws': gravity-based TWS uncertainties3) 'model_atmosphere': background model atmospheric mass These Level-3 products are visualized at GFZ's web portal GravIS (http://gravis.gfz-potsdam.de). Link to data products: ftp://isdcftp.gfz-potsdam.de/grace/GravIS/GFZ/Level-3/TWS
# 3
Bindi, Dino • Zaccarelli, Riccardo • Strollo, Angelo • Di Giacomo, Domenico
Abstract: In Bindi et al. (2019) a harmonized local magnitude scale across Europe has been derived using data disseminated by network operators through the European Integrated Data Archive (EIDA). This data set contains regionalized non-parametric attenuation tables, attenuation corrections to the parametric model and station corrections for both non-parametric and parametric models for more than 2000 stations in Europe. Regionalization has been performed considering six different regions covering Europe and the polygons defining them are also provided. Data are subject to updates that can be triggered by the availability of new and substantial input data (reviewed earthquake catalogues and/or new waveforms). Each update will be released with a new version of the data. The data are provided in ASCII format (.csv).
# 4
Zaccarelli, Riccardo
Abstract: The task of downloading comprehensive datasets of event-based seismic waveforms has been made easier through the development of standardised web services, but is still highly non-trivial, as the likelihood of temporary network failures or even worse subtle data errors naturally increase when the amount of requested data is in the order of millions of relatively short segments. This is even more challenging as the typical workflow is not restricted to a single massive download but consists of fetching all possible available input data (e.g., with several repeated download executions) for a processing stage producing any desired user-defined output. Here, we present stream2segment, a highly customisable Python 2+3 package helping the user through the whole workflow of downloading, inspecting and processing event-based seismic data by means of a relational database management system as archiving storage, which has clear performance and usability advantages. Stream2segment provides an integrated processing implementation able to produce any kind of user-defined output based on a configuration file and a user-defined Python function. Stream2segment can also produce diagnostic maps or user-defined plots which, unlike existing tools, do not require external software dependencies and are not static images but interactive browser-based applications ideally suited for data inspection or annotation tasks.
# 5
Kwiatek, Grzegorz • Saarno, Tero • Ader, Thomas • Bluemle, Felix • Bohnhoff, Marco • (et. al.)
Abstract: The dataset is supplementary material to Kwiatek et al. (2019, Science Advances). The dataset is a refined seismic catalog acquired during the hydraulic stimulation of the future geothermal sites located in Espoo, Finland. There, the injection well, OTN-3, was drilled down to 6.1 km-depth into Precambrian crystalline rocks. Well OTN-3 was deviated 45° from vertical and an open hole section at the bottom was divided into several injection intervals. A total of 18,159 m3 of fresh water was pumped into crystal-line rocks during 49 days in June- and July, 2018. The stimulation was monitored in near-real time using (1) a 12-level seismometer array at 2.20-2.65 km depth in an observation well located ~10 m from OTN3 and (2) a 12-station network installed in 0.3-1.15 km deep bore-holes surrounding the project site. On completion of stimulation it the catalog contained 8452 event detections overall, and 6152 confirmed earthquakes located in the vicinity of the project site (epicentral distance from the well head of OTN-3 <5 km). These were recorded in a time period lasting 59 days: 49 days of active stimulation campaign and the 10 days following completion. The initial industrial seismic catalog of 6150 earthquakes was manually reprocessed. The P- and S-wave arrivals of larger seismic events with M>0.5 were all manually verified, and, if necessary, refined. Earthquakes with sufficient number of phases and seemingly anomalous hypocenter depths (e.g. very shallow or very deep) were manually revised as well. The hypocenter locations were calculated using the Equivalent differential time method and optimized with an Adaptive Simulated Annealing algorithm. The updated catalog contained 4,580 earthquakes that occurred at hypocenter depths 4.5-7.0 km, in the vicinity of the stimulation section of OTN-3. To increase the precision of their locations, the selected 2155 earthquakes with at least 10 P-wave and 4 S-wave picks were relocated using the double-difference relocation technique. The relocation uncertainties were estimated using bootstrap resampling technique. The relocation reduced the relative precision of hypocenter determination to approx. 66 m and 27 m for 95% and 68% of relocated earthquakes. The final relocated catalog that constitutes the here published contained 1,977 earthquakes (91% of the originally selected events).
# 6
König, Rolf • Schreiner, Patrick • Dahle, Christoph
Abstract: As a convenience to users who wish to use a replacement value for C(2,0) of GFZ's GRACE/GRACE-FO RL06 GSM products, a monthly GFZ C(2,0) estimate time series is provided. These estimates are obtained from the analysis of Satellite Laser Ranging (SLR) data to the following five geodetic satellites: LAGEOS-1 and 2, Starlette, Stella and Ajisai. Starting from March 2012, the LARES satellite is added so that six geodetic satellites are included. The individual satellites are combined on normal equation level using relative weights which are based on a variance component estimation. Gravity field coefficients up to degree and order 5 plus coefficients C(6,1) and S(6,1) have been simultaneously solved together with all other (non-gravity) parameters. The background models used in the SLR analysis is consistent with the GFZ GRACE/GRACE-FO RL06 processing, including the use of the same Atmosphere-Ocean De-aliasing product AOD1B RL06. IMPORTANT REMARKS: It is advised to use these estimates to replace the C(2,0) values from the GFZ RL06 GSM files. These estimates are not intended to be used with the GRACE RL05 or earlier products. This data set is regularly updated in order to extend the time series on an operational basis. As long as the version number has not changed, all previously available data records have not been changed! See line 'UPDATE HISTORY' in the header of the data file for details about the current time span and version. SPECIAL NOTES: C(2,0) estimates are provided continuously for each month. However, the SLR data was processed in 7-day batches aligned to GPS weeks. Several weekly SLR normal equations were then accumulated to obtain a monthly solution; GPS weeks covering two calendar months were assigned to that calendar month where the majority of days within the week belong to. Thus, the beginning date for these 'monthly' solutions does not necessarily match the first day of a calendar month, but will be within a few days of that corresponding date. Moreover, in most cases, a different number of days was used for the SLR solution than for the corresponding GRACE/GRACE-FO solution. For particular periods, the GRACE/GRACE-FO solutions might span significantly less than one month or cover more than one calendar month. In these cases, a specially dedicated SLR estimate was generated which is based on approximately the same interval so that the epoch of the SLR estimate is close to the epoch of the GRACE/GRACE-FO solution. To distinguish the different cases of C(2,0) estimates mentioned above (monthly vs. specially dedicated) and to easily recognize whether a C(2,0) estimate matches an existing GRACE/GRACE-FO solution, the following flags are appended to each data record:- ' m': C(2,0) estimate represents a monthly solution for a month where no GRACE/ GRACE-FO solution is available.- 'Gm': C(2,0) estimate represents a monthly solution and a corresponding GRACE/ GRACE-FO solution is available.- 'G*': C(2,0) estimate is specially dedicated for a GRACE/GRACE-FO solution as described above; the effective period of data used is additionally provided by a string '<yymmdd>_<YYMMDD>'.
# 7
Dahle, Christoph • Murböck, Michael
Abstract: Post-processed GRACE/GRACE-FO spherical harmonic coefficients of GFZ RL06 Level-2 GSM products representing an estimate of Earth's gravity field variations during the specified timespan. Post-processing steps comprise: (1) subtraction of a long-term mean field; (2) optionally, decorrelation and smoothing with VDK filter (anisotropic filter taking the actual error covariance information of the underlying GSM coefficients into account, see Horvath et al. (2018)); (3) replacement of coefficient C20 and its uncertainty by values estimated from Satellite Laser Ranging (SLR); (4) subtraction of linear trend caused by Glacial Isostatic Adjustment (GIA) as provided by a numerical model; (5) insertion of coefficients of degree 1; and (6) removal of estimated signal with 161 days period. These coefficients represent signals caused by water mass redistribution over the continents and in the oceans. These post-processed GRACE/GRACE-FO GSM products are denoted as Level-2B products. There are multiple variants of Level-2B products available that differ by the characteristics of the anisotropic filter applied. These variants are distinguishable by the following strings in the product file names: - 'NFIL': Level-2B product is not filtered- 'VDK2': Level-2B product is filtered with VDK2- 'VDK3': Level-2B product is filtered with VDK3- 'VDK5': Level-2B product is filtered with VDK5 The individual data sets and models used during the post-processing steps mentioned above are provided as well (in the aux_data folder): - 'GRAVIS-2B_2002095-2016247_GFZOP_0600_NFIL_0001.gz': Long-term mean field calculated as unweighted average of the 156 available GFZ RL06 GSM products in the period from 2002/04 up to and including 2016/08.- 'GFZ_RL06_C20_SLR.dat': C20 time series from SLR (http://doi.org/10.5880/GFZ.GRAVIS_06_C20_SLR)- 'GRAVIS-2B_GIA_ICE5G_VILMA.gz': Model for subtraction of linear trend caused by GIA- 'GRAVIS-2B_DEG1_v01.dat': Degree-1 time series Detailed information about the product is provided in the header of the data file.
# 8
van Dongen, Renee • Scherler, Dirk • Wittmann, Hella • von Blanckenburg, Friedhelm
Abstract: Concentrations of in-situ-produced cosmogenic 10Be in river sediment are widely used to estimate catchment-average denudation rates. Typically, the 10Be concentrations are measured in the sand fraction of river sediment. However, the grain size of bedload sediment in most bedrock rivers covers a much wider range. Where 10Be concentrations depend on grain size, denudation rate estimates based on the sand fraction alone are potentially biased. To date, knowledge about catchment attributes that may induce grain-size-dependent 10Be concentrations is incomplete or has only been investigated in modelling studies. Here we present an empirical study on the occurrence of grain-size-dependent 10Be concentrations and the potential controls of hillslope angle, precipitation, lithology, and abrasion. We first conducted a study focusing on the sole effect of precipitation in four granitic catchments located on a climate gradient in the Chilean Coastal Cordillera. We found that observed grain size dependencies of 10Be concentrations in the most-arid and most-humid catchments could be explained by the effect of precipitation on both the scouring depth of erosion processes and the depth of the mixed soil layer. Analysis of a global dataset of published 10Be concentrations in different grain sizes (n=73 catchments) – comprising catchments with contrasting hillslope angles, climate, lithology, and catchment size – revealed a similar pattern. Lower 10Be concentrations in coarse grains (defined as “negative grain size dependency”) emerge frequently in catchments which likely have thin soil and where deep-seated erosion processes (e.g. landslides) excavate grains over a larger depth interval. These catchments include steep (> 25°) and humid catchments (> 2000mm yr-1). Furthermore, we found that an additional cause of negative grain size dependencies may emerge in large catchments with weak lithologies and long sediment travel distances (> 2300–7000 m, depending on lithology) where abrasion may lead to a grain size distribution that is not representative for the entire catchment. The results of this study can be used to evaluate whether catchment-average denudation rates are likely to be biased in particular catchments. Samples from the Chilean Coastal Cordillera were processed in the Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES). 10Be/9Be ratios were measured at the University of Cologne and normalized to the KN01-6-2 and KN01-5-3 standards. Denudation rates were calculated using a time-independent scaling scheme according to Lal (1991) and Stone (2002) (St scaling scheme) and the SLHL production rate of 4.01 at g-1 yr-1 as reported by Phillips et al. (2016) The global compilation exists of studies that measured 10Be concentrations in different grain sizes from the same sample location. We only included river basins of <5000 km2 which measured 10Be concentrations in at least one sand-sized fraction <2 mm and at least one coarser fraction >2 mm. Catchment parameters have been recalculated using a 90-m SRTM DEM. The data are presented in Excel and csv tables. Table S1 describes the characteristics of the samples catchments, Table S2 includes the grain size dependent 10Be-concentrations measured during this study and Table 3 the global compilation of grain size dependent 10Be-concentrations. All samples of this study (the Chilean Coastal Cordillera) are assigned with International Geo Sample Numbers (IGSN). The IGSN links are included in Table S2 and in the Related References Section on the DOI Landing Page. The data are described in detail in the data description file and in van Dongen et al. (2018) to which they are supplementary material to.
# 9
Dietze, Elisabeth • Dietze, Michael
Abstract: 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).
# 10
Dreiling, Jennifer • Tilmann, Frederik
Abstract: BayHunter is an open source Python tool to perform an McMC transdimensional Bayesian inversion of receiver functions and/ or surface wave dispersion. It is inverting for the velocity-depth structure, the number of layers and noise parameters (noise correlation and amplitude). The forward modeling codes are provided within the package, but are easily replaceable with own codes. It is also possible to add (completely different) data sets. The BayWatch module can be used to live-stream the inversion while it is running: this makes it easy to see how each chain is exploring the parameter space, how the data fits and models change and in which direction the inversion progresses.
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