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Data from the GRANU95 seismic refraction experiment

The occurrence of exposed high-metamorphic rocks (granulites) in combination with various gravity anomalies aligned along the direction of Variscan strike characterize a special terrain (Saxothuringikum) which has been sandwiched between two major tectonic units during the Variscan orogeny. Near surface geological studies show evidence that the Saxothuringian zone represents extended crust. Therefore the model of a "metamorphic core complex" is often used to explain the exhumation of the "Saxonian granulites". The thickness of the crust, the geometry of the Moho, and the composition of middle and lower crust that underlie such" metamorphic core complexes" have remained largely unconstrained. Because these physical parameters are critical for understanding the extensional processes acting at depth, we have carried out a seismic refraction experiment in order to resolve the deeper structure of an exposed "granulite-complex". From May 6th to May 13th 1995 a seismic refraction - wide angle reflection experiment was carried out as part of the DFG-priority program: "Orogenic processes – their quantification and simulation at the example of the Variscides". Two lines, A and B, were completed in two deployments (see map in GRANU95_report.pdf). In total 12 shots were fired and over 4500 seismograms were collected using 130 instruments. Only two different types of instruments (Reftek and PDAS) have been used for recording the explosions. All instruments were equipped with a 3-component 1Hz seismometer. The 90 km long NW-SE line (deployment A, 74 instruments) from Leipzig to the Erzgebirge through the Saxonian Granulites was carried out on the 8th and 9th May 1995. Additionally 56 stations were placed symmetrically to shotpoint D along line B (perpendicular to line A). Shots were fired on locations A1, A3, A4, A2 (see map in GRANU95_report.pdf). The station spacing for this deployment was around 1.3 km. The 260 km long SW-NE line (deployment B, 93 instruments) from Dresden to Bamberg, also crossing the Saxonian Granulites was completed from 11th to 13th May 1995. Every second instrument from deployment A was moved to complete line B. Shots were fired on locations B, C, D, E, F, G, H and I (see map in GRANU95_report.pdf) and recorded along line B and line A (perpendicular to line B) at a receiver spacing of about 2.6 km.

On-shore data of the amphibious part of the refraction-seismic project INGON in and around Sri Lanka (RV SONNE cruise SO258/2)

In July and August 2017, off-shore seismic measurements have been carried out south of Sri Lanka as part of the INGON project. Main aim of this part of the project was to study the deep structure of the continent-ocean transition south of Sri Lanka and the early plate drift of India and Sri Lanka. The marine profile was extended by 15 seismic stations on-shore Sri Lanka, of which the data is contained in this data publication (land observations of airgun sources). This dataset consists of the raw (continuous) data of the land recorders (in proprietary cube and MSEED formats) and the shot records (airgun sources) in SEGY-format (standard exchange format).

Data from the 1978-79 Rhenish Massif seismic refraction experiment

During 1978-79, a seismic refraction experiment was carried out in the Rhenish Massif, West Germany, and adjacent areas, extending through Belgium and Luxembourg into the Paris Basin in France. The experiment was designed to investigate the structure of the crust and uppermost mantle beneath the massif and thus help in a multidisciplinary study, sponsored by the Deutsche Forschungsgemeinschaft, into the causes and mechanisms of uplift of the massif. The Aachen-Baumholder (L1/L2-M1/M2) profile was completed in May and August, 1978. The 600 km long, main profile and the cross profiles, B-K and K-F, were completed in May 1979. During the main experiment in May 1979, 137 recording units of the MARS type from various European countries participated. 20 shots were fired in 1979 and thus a total of 2740 three-component recordings were made.

Data of the Western Makran Seismic Transects (Iran)

In September 2017 three crustal-scale seismic profiles were acquired in southern Iran covering the subaerial accretionary wedge of the western part of the Makran Subduction zone. Each of the roughly north-south trending profiles was approximately 200 km long, and on each profile 9 to 10 artificial shots with charges between 400 and 800 kg of explosives were fired. The seismic signals were observed by 300 autonomous digital recorders with geophones on each profile. This dataset consists of the raw (continuous) data of the recorders (in proprietary cube format and MSEED-format) and the shot records in SEGY-format (standard exchange formats).

Land seismic data of the ALPHA amphibious controlled source experiment - Datasets

Raw-, SEG-Y and other supplementary data of the landside deployment from the amphibious wide-angle seismic experiment ALPHA are presented. The aim of this project was to reveal the crustal and lithospheric structure of the subducting Adriatic plate and the external accretionary wedge in the southern Dinarides. Airgun shots from the RV Meteor were recorded along two profiles across Montenegro and northern Albania.

Data of the amphibious wide-angle seismic experiment in south Turkey, Cyprus and south of Cyprus (Eratosthenes Seamount) in the framework of the CyprusArc project (March 2010) - Datasets

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.