KIT | KIT-Bibliothek | Impressum | Datenschutz

Present-day stress control on fluid migration pathways: Case study of the Zechstein fractured carbonates, NW-Germany

Becker, Ivy; Müller, Birgit; Koehrer, Bastian; Jelinek, Wolfgang; Hilgers, Christoph

Understanding the orientation and connectivity of fracture systems in tight reservoirs is essential to reduce uncertainties in reservoir development and production. However, the actual flow potential of the fractures can be controlled by the present-day stress field. Dilation- and slip tendency analyses can improve fracture permeability evaluations and thus, aid in estimating the hydrocarbon recovery of a field.

This study focuses on a naturally-fractured, relatively tight (matrix permeabilities of 0.01–1 mD) and gas-producing Late Permian (Zechstein) reservoir in the Southern Permian Basin, northern Germany. Fracture data are obtained from resistivity image log data of a 775 m long horizontal well, and show principal NE – SW orientation with main dip angles steeper than 70°. To quantify the potential of those fractures that contribute to the flow within the reservoir, dilation (Td)- and slip (Ts) tendencies are calculated. Two different stress scenarios are defined based on known variations in the orientation of the horizontal stresses between formations below and above the Zechstein salt in an offset field approximately 5 km away.

Results of Td and Ts strongly depend on the strike and dip angle of the fractures, with sub-vertical fractures showing highest potential to dilate while fractures with dip angles of 60° are favorably oriented for slip. ... mehr

DOI: 10.1016/j.marpetgeo.2019.03.002
Zugehörige Institution(en) am KIT Institut für Angewandte Geowissenschaften (AGW)
Publikationstyp Zeitschriftenaufsatz
Jahr 2019
Sprache Englisch
Identifikator ISSN: 0264-8172
KITopen-ID: 1000092074
Erschienen in Marine and petroleum geology
Band 103
Seiten 320–330
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page