Decoupling of deformation in the Upper Rhine Graben sediments. Seismic reflection and diffraction on 3-component Vertical Seismic Profiling (Soultz-sous-Forets area)

作者：Place Joachim^*; Diraison Marc; Naville Charles; Geraud Yves; Schaming Marc; Dezayes Chrystel

来源：Comptes Rendus Geoscience, 2010, 342(7-8): 575-586.

DOI：10.1016/j.crte.2010.01.001

• Upper Rhine Graben
• Tertiary tectonics
• Decollement
• Tilted block
• Seismic reflection
• Three-component (3C) VSP
• Diffraction

A contribution to the definition of the structural pattern of the Soultz-sous-Forets EGS (Enhanced Geothermal System) is presented here. After reprocessing, the PHN84J seismic reflection profile highlights the tilted blocks of the Merkwiller-Pechelbronn oilfield. In the Soultz-sous-Forets horst, complex fault patterns are observed: the Hermerswiller normal fault flattens at depth and is rooted in decollements occurring in Triassic salt or clay series, while other steep normal faults affect underlying sedimentary formations and basement. Some methods for the exploitation of a seismic diffraction recorded by multi-component Vertical Seismic Profiling (VSP) are also illustrated to locate the diffractor without specific data processing. Polarisation and travel time analysis of a diffraction event recorded in the GPK1 borehole are analysed, and its exploitation combined with seismic reflection helps defining a tilted block geometry.

• 出版日期2010-8