ALBERT

Description: Abstract

Description: In August and September 2013, 17 shallow ocean bottom seismograph (S-OBS) stations and 8 land stations had been deployed on and around Muostakh Island (Laptev Sea, Russia) for a time period of 24 days. The specifically designed underwater recording equipment consists of a low-power digital recorder, a standard 4.5Hz 3-component geophone, and a battery pack. These components are enclosed in a watertight cylindrical container safe for operation down to 100m water depth. Land stations were also equipped with 4.5 Hz 1C-geophones as well as with batteries. All instruments recorded continuously with 200 samples per second (sps). The stations were deployed along two profiles covering a region of 8km x 8 km. The tilt of the geophone inside the S-OBS influences the sensor characteristics. Since the orientation and tilt at the ocean bottom was unknown, approximately every 24 hours a calibration signal (a sequence of step-functions) was applied to the sensors of the ocean stations. This might be used to recover the actual sensor characteristics (eigenfrequency and damping). The dataset contains 1) a info-folder with a) a README file; b) a file containing the times when calibration signals occurred (format: recorder_ID - date - time); c) the station table (ASCII; recorder_ID - latitude - longitude - (water)depth); d) a map of the region with the locations of the stations; 2) raw CUBE-formatted data; 3) converted mini-seed-formatted data (hourly files).

Description: The 2014 LoNNe (Loss of the Night Network) intercomparison campaign is the third of four campaigns planned during EU COST Action ES1204. This report provides a brief synopsis of the campaign and its preliminary outcomes. Section 2 describes the measurement locations, the activities of the participants, the instruments used, and the environmental conditions. Section 3 describes a public outreach event held during the campaign. Section 4 provides some preliminary results, outlines the ongoing analyses, and presents research questions for the next campaign to address. Section 5 provides recommendations for the final LoNNe intercomparison campaign in 2016. Section 6 concludes the report.

Description: The ability of any satellite gravity mission concept to monitor mass transport processes in the Earth system is typically tested well ahead of its implementation by means of various simulation studies. Those studies often extend from the simulation of realistic orbits and instrumental data all the way down to the retrieval of global gravity field solution time-series. Basic requirement for all these simulations are realistic representations of the spatio-temporal mass variability in the different sub-systems of the Earth, as a source model for the orbit computations. For such simulations, a suitable source model is required to represent (i) high-frequency (i.e., sub-daily to weekly) mass variability in the atmosphere and oceans, in order to realistically include the effects of temporal aliasing due to non-tidal high-frequency mass variability into the retrieved gravity fields. In parallel, (ii) low-frequency (i.e., monthly to interannual) variability needs to be modelled with realistic amplitudes, particularly at small spatial scales, in order to assess to what extent a new mission concept might provide further insight into physical processes currently not observable. The new source model documented here attempts to fulfil both requirements: Based on ECMWF’s recent atmospheric reanalysis ERA-Interim and corresponding simulations from numerical models of the other Earth system components, it offers spherical harmonic coefficients of the time-variable global gravity field due to mass variability in atmosphere, oceans, the terrestrial hydrosphere including the ice-sheets and glaciers, as well as the solid Earth. Simulated features range from sub-daily to multiyear periods with a spatial resolution of spherical harmonics degree and order 180 over a period of 12 years. In addition to the source model, a de-aliasing model for atmospheric and oceanic high-frequency variability with augmented systematic and random noise is required for a realistic simulation of the gravity field retrieval process, whose necessary error characteristics are discussed. The documentation is organized as follows: The characteristics of the updated ESM along with some basic validation are presented in Volume 1 of this report (Dobslaw et al., 2014). A detailed comparison to the original ESA ESM (Gruber et al., 2011) is provided in Volume 2 (Bergmann-Wolf et al., 2014), while Volume 3 (Forootan et al., 2014) contains a description of the strategy to derive a realistically noisy de-aliasing model for the high-frequency mass variability in atmosphere and oceans. The files of the updated ESA Earth System Model for gravity mission simulation studies are accessible at DOI:10.5880/GFZ.1.3.2014.001.

Description: SEGY and supplementary data of the seismic reflection experiment in the Baza Basin (Southern Spain). Presented are unstacked and unmigrated data of three 2D vibroseis profiles which were carried out in October 2013 and all corresponding raw data.

Description: This publication is a result of the 13th TRACE conference (Tree Rings in Archaeology, Climatology and Ecology) organized by the Department of Earth and Environmental Sciences at the University of St Andrews on May 6th – 10th, 2014 in Aviemore, Scotland, UK. [...]After review, 18 short papers are published in this volume, giving an overview of the wide spectrum of different fields covered at TRACE.

Description: The Global Navigation Satellite System (GNSS) plays a significant role in the fields of airborne gravimetry. The objective of this thesis is to develop reliable GNSS algorithms and software for kinematic highly precise GNSS data analysis in airborne gravimetry.

Description: Raw-, SEG-Y and other supplementary data of the amphibious wide-angle seismic experiment carried out in South Turkey, Cyprus and south of Cyprus are presented. The aim of this project was to reveal the crustal structure of the Anatolian plateau, Cyprus and the Eratosthenes Seamount (ESM), south of Cyprus. Simultaneous data acquisition offshore with ocean bottom seismometers and airguns and onshore with seismic land stations and two land shots in South Turkey lead to a 650 km long amphibian seismic profile.

Description: This report as well as the associated data is a supplement to the publication Blöcher et al. (2015) accessible via DOI: 10.1016/j.geothermics.2015.07.008. From 2011-06-01 until 2013-12-31, the measurement and control system at the Groß Schönebeck research platform acquired data from several circulation experiments. Different data values were recorded at a sampling interval of 1 s. Relevant data for understanding and analyzing the hydraulic situation of the system were resampled to a 1 minute interval. From the resampled dataset, additional parameters were derived. Furthermore, if parameters were considered to be essential, but the measurement of these parameters was erroneous, some data were reprocessed. All relevant data and processing steps performed on the data are described within this report. Data described within this report can be accessed via DOI:10.5880/GFZ.b103-15021.1. The presented data was acquired during different research projects by the staff of the International Centre for Geothermal Research as well as Section 4.1 Reservoirtechnologies at the Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences.

Description: Dieser Leitfaden entstand im dreijährigen Projekt „Konzeption und Erprobung von Modellen für forschungsnahe Transferstrukturen in der außeruniversitären Forschung“ – kurz TMod – auf Initiative von zwei Leibniz-Instituten und drei Helmholtz-Zentren unter Projektkoordination durch das Helmholtz-Zentrum Potsdam - Deutsches Geoforschungszentrum GFZ und unter Förderung durch das BMBF, wobei sich der Kreis der Projektpartner im Projektverlauf auf insgesamt neun Einrichtungen erweiterte. Die Beteiligten waren auf der Suche nach zeitgemäßen Instrumenten, mit denen die Ergebnisse und Leistungen ihrer Wissenschaftler effektiver zu echten Innovationen werden. Die unterschiedlichen Erfahrungen, die es bis dahin mit Ausgründungen zur Professionalisierung des Wissens- und Technologietransfers gab, waren sehr unterschiedlich und vorwiegend quantitativ abstrakt aufgearbeitet. Es gab daher gerade bei mittleren und kleinen außeruniversitären Forschungseinrichtungen einen Bedarf nach fundiertem und strukturiertem Anwendungswissen, um eine entsprechende Umstrukturierung zu erleichtern. Das Projekt TMod kam diesem Bedarf mit einer Analyse von Best Practices, der Klärung offener Fragestellungen und einer darauf aufbauenden individuellen Konzeptentwicklungs- und Umsetzungsunterstützung entgegen. Der so entstandene Leitfaden soll wissenschaftliche Einrichtungen, die Ihren Technologietransfer professionalisieren wollen, praktisch unterstützen und sie vom gewonnenen Wissen im Projekt TMod profitieren lassen.

Description: The acronym EMERALD was supposed to stand for ElectroMagnetic Equipment, Raw data And Locations Database. What survived over the years was the EMERALD processing, a set of computer programs to analyse MT time series data, and the EMERALD file format for storing MT data. This document describes the EMERALD file format and how to use it with the C++, C and FORTRAN programming languages. Interface functions also exist for Matlab and Powershell but they are not described here. EMERALD data files typically come in pairs of two files with the same name but differing file name extensions, sometimes called RAW and XTR files. XTR (extract) files are plain ASCII files, which can be read and modified with text editors. RAW files or more generally, EMERALD ‐type data files are in most cases binary and used to store all kind of magnetotelluric (MT) data such as time series, cross‐ and auto spectra and calibration data. The EMERALD ‐type data files store any number of channels of data in matrix form, but do not contain any description of the data. This information is stored in the according XTR file. In 2015 the original XTR files were replaced by a modernized version based on the Extensible Markup Language (XML). The new files have the extension .XTRX.

Description: The sources for the magnetotelluric method are naturally occurring electromagnetic field variations. Electromagnetic currents are excited over a wide frequency range in the earth’s ionosphere by solar activity and global lighting discharges. While these source are available everywhere on earth and at all times, their signal strength varies considerably. The so-called remote-reference technique is an effective way to improve magnetotelluric data quality by referencing the electromagnetic fields recorded at a local site to simultaneously recorded, undisturbed fields at a remote site. The remote reference approach has become standard for magnetotelluric field work, particularly in areas with high levels of man-made electromagnetic noise; i.e. almost everywhere in central Europe. Identifying a suitable location for a clean remote site is difficult and time-consuming. Maintaining such a site in addition to normal field operations is expensive and logistically challenging. A permanently installed reference station simplifies MT measurements considerably. The radius for which source fields are coherent depends mostly on the frequency content of the signals and the latitude of observations. According to our own tests, signals are coherent at frequencies of up to 10 kHz over distances of 1000 km. After a reconnaissance operation during which several locations all over Germany were tested, we could eventually identify an urban forest near the town of Wittstock in northern Germany as a suitable location for a reference station. A preliminary installation of the reference station was accomplished by mid-2010. The permanent installation in a wooden hut and operating with a range of sensors and sampling rates is available since November 2010. Meanwhile the data of the Wittstock site have been used very successfully to re-process a number of magnetotelluric stations in Germany. This report describes the installation, the type of sensors and the recorded data sets, which are freely available on request. For updated material, please refer to our webpages (http://www.gfz-potsdam.de/en/section/geophysical-deep-sounding/servicesinfrastructure/geophysical-instrument-pool-potsdam-gipp/archive/mt-reference-site/)