Abstract
The profile DEKORP 3B/MVE, consisting of the two segments West and East, was recorded in 1990 as part of the DEKORP project, the German deep seismic reflection program. The focus of the DEKORP project was on deep crustal and lithospheric structures and therefore originally not on structures at shallower depths. From today's perspective, however, this depth range is of great interest for a wide range of possible technical applications (including medium-depth and deep geothermal projects). The original data is published by Stiller et al. (2021). The westernmost 91 km of the 208 km long profile 3B (West) were reprocessed on behalf of the Hessian Agency of Nature Conservation, Environment and Geology (HLNUG). As a particularity, also a set of 18 cross-lines, each ca. 12 km in length and perpendicular to the main lines, were surveyed along DEKORP 3B/MVE to get information about possible cross-dips. Four of those short cross-lines were reprocessed in 2D as well. The focus of the reprocessing of the old data was on improving the resolution / mapping of geological structures down to a depth of 6 km (approx. 3 s TWT) to describe the prolongation of faults and geological structures in more detail than in previous studies.
In order to achieve these goals and in view of the fact that today's processing and evaluation methods have been improved considerably compared to the 1990‘s, a state-of-the-art reprocessing was implemented. In comparison with the original processing (Stiller et al. (2021)), more sophisticated processing steps like CRS (Common Reflection Surface) instead of CDP (Common Depth Point) stacking, turning-ray tomography and prestack time and depth migration were carried out.
The reprocessing results of the DEKORP 3B (West) survey comprise all datasets newly achieved in addition to the datasets from the original processing (Stiller et al. (2021)), i.e. (1) the migrated CRS image gathers as unstacked data, and (2) the pure CRS stack, the poststack-time as well as prestack-time and prestack-depth migrated sections as stacked data. Moreover, (3) all velocity models used for the different versions including (4) the separate first-break tomography inversion, are contained. Additionally, the results of the 2D-reprocessing of cross-lines Q21-Q24 are included.
All reprocessed data come in SEGY trace format, the final sections additionally in PDF graphic format. A reprocessing report is included as well as again all meta information for each domain (source, receiver, CDP) like coordinates, elevations, locations and static corrections combined in ASCII-tables for geometry assignment purposes.
The DEKORP 3 survey was a combined seismic survey investigating the Variscan structures of the Rhenohercynian and the Saxothuringian. Consisting of three seismic lines it starts in the Rhenohercynian Hessian Depression (DEKORP 3A), crosses the Saxothuringian Mid-German Crystalline High (DEKORP 3B/MVE (West)) and runs parallel to the northern margin of the Moldanubian (DEKORP 3B/MVE (East)). The 207.65 km long DEKORP 3B (West) profile trends NW-SE and intersects DEKORP 3A in the Tertiary volcanic field within the "Northern Phyllite Zone". It crosses the Hessian Depression of the Rhenohercynian, runs through the Rhön Tertiary volcanic province and the Mesozoic Franconian Basin to the Bohemian Massif. The line ends at the Franconian Line. The reprocessed datasets contain a sub-section of the entire 3B (West) profile with a total length of 90.8 km of full CDP coverage, covering the territory of the state of Hesse, i. e. from the profile’s starting point in the NW to the SE until the Rhön volcanic complex. The reprocessed part of 3B (West) is intersected by four short cross-lines along the profile at km 8.75, 32.6, 64.75, 84.35 and by DEKORP 3A at km 42.3.
The DEKORP '90-3B profile is of particular interest to investigate the seismic resolution of the Hessian depression, the east-hessian Buntsandstein nappe as well as the tertiary volcanic fields of the Kellerwald and Rhön.
