Upper Triassic – Cretaceous stratigraphy and structural inversion off-shore SW Bornholm, Tornquist Zone, Denmark

Bulletin of the Geological Society of Denmark

Obst, K.¹  Maletz, J.:¹  Katzung, G.¹  Böhnke, A.¹ 

[1] Pb-Pb zircon dating of tuff horizons inthe Cyrtograptus Shale (Wenlock, Silurian) of Bornholm, Denmark. Bulletin of the Geological Society of Denmark, Vol. 49, pp. 1–8, Copenhagen.

关键词: Bornholm;    Tornquist Ocean;    Wenlock;    Silurian;    tuff;    graptolites;    Pb-Pb isotopes;    singlezircon evaporation.;   

学科分类：地球科学(综合)

来源: Dansk Geologisk Forening

【 摘 要 】

Geological interpretations by various authors of exploration reflection seismic data offshore SW Bornholm show good agreement for the Rønne Graben. However, major differences exist regarding the Mesozoic stratigraphy and structural development of the Arnager-Darlowo Block and the Risebæk Graben. Major problems relate to the distribution and structural position of the Jurassic, and interpretation of inversion structures in the Rønne and Kolobrzeg grabens along the Arnager Block. In addition to the Pernille-1 and Stina-1 wells that document the stratigraphy of the Rønne and Kolobrzeg graben sections, the bedrock geology along the south coast of Bornholm is discussed.The Jurassic is established as a major constituent of the Arnager Block above the Risebæk Graben, in contrast to previous interpretations. The revised stratigraphy and reinterpretation of the inversion zones help to establish a new interval of basin inversion during the Jurassic – Early Cretaceous priorto the Late Cretaceous inversion. Analysis of the Late Cretaceous inversion across the Rønne Graben supports the proposed revision of the stratigraphy and leads to a new model. Previous interpreta-tions invoked a major uplift of the graben along a reverse fault at the eastern border of the Rønne Graben. In the new model, Late Cretaceous inversion across the Rønne Graben is associated withtilting of the graben during differential subsidence/uplift of the Skurup Platform and the Arnager Block, whereas reverse faulting was limited.

【 授权许可】

Unknown