Open AccessGeological mapping of Mesozoic deposits along the eastern margin of the R0nne Graben, offshore Bornholm, Denmark
Author(s) -
Jørn Bo Jensen,
Niels Erik Hamann
Publication year - 1989
Publication title -
bulletin of the geological society of denmark
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.674
H-Index - 28
eISSN - 2245-7070
pISSN - 0011-6297
DOI - 10.37570/bgsd-1988-37-19
Subject(s) - geology , graben , cretaceous , echelon formation , horst and graben , mesozoic , sinistral and dextral , tectonics , paleontology , submarine pipeline , fault (geology) , strike slip tectonics , seismology , geomorphology , structural basin , geotechnical engineering
Detailed shallow seismic investigations of the eastern R0nne Graben, offshore Bomholm have resulted in the recognition of characteristic seismic facies which are subdivided into seismostratigraphic units. The seismostratigraphic units are correlated with known lithostratigraphic units on Bomholm, thus permitting detailed geological mapping along the eastern margin of the Rønne Graben. In contrast to the sequence on Bomholm, it appears that there was continuous sedimentation from the R0nne Formation (Lower Jurassic) to the Rabekke Formation (Lower Cretaceous), while the Robbedale and Jydegard Formations (Lower Cretaceous) are absent in the R0nne Graben. In the area mapped in detail the youngest Pre-Quaternary sediments are the Arnager Greensand, the Amager Limestone and the Bavnodde Greensand Formations (Upper Cretaceous). All the Mesozoic deposits were affected by transpressional tectonic activity during the Upper Cretaceous - Lower Tertiary. The structural relationships show a characteristic pattern consisting of the main fault on the eastern side of the Rønne Graben and a system of en echelon reverse faults. This pattern probably formed as a result of northeast-southwest wrench movements in a compressional dextral strike slip system.