Monitoring Fractures in 4D Using Microseismic Data

Summary MONITORING FRACTURES IN 4D USING MICROSEISMIC DATA A. J. CALEY 1 J-M.KENDALL 2 R.H.JONES 3 O. I. BARKVED 4 and P. G.FOLSTAD 4 1 University of Leeds School of Earth Sciences LS2 9JT U.K.� now at Schlumberger Gatwick RH6 ONZ U.K. 2 University of Leeds School of Earth Sciences Leeds LS2 9JT U.K. 3 ABB O shore Systems Limited Rosemanowes Penryn TR10 9DU U.K. 4 BP Amoco Norge A.S. Godesetdalen 8 PO Box 197 4065 Stavanger Norway. Seismic anisotropy in the Valhall eld North Sea is estimated from observations of shearwave splitting in microseismic events. Nearly 324 events recorded