Use of outcrop analogues in fractured reservoir characterization - an example from the Dezful Embayment, SW-lran

摘要

Several giant oil fields in the Dezful Embayment in SW Iran (Figure 1) produce from the carbonates of the Asmari Formation (Late Oligocene -Early Miocene), where production depends strongly on the existence of fracture networks (e.g. Ogilvie et al, this volume). However, the fracture characterization is in some cases hampered by a limited dataset on static parameters derived from core and image logs. Seismic coverage is in general poor and consequently the structural definition is coarse. Also, well and core data in general do not contain information on important fracture characteristics like length distribution, crosscutting relationships and fracture density as a function of bed thickness or facies. Fortunately, outcrops of the Asmari Formation are found in close proximity to the giant oilfields. A detailed investigation of one of these outcrops - the Khaviz Anticline - was carried out to improve the database for different fracture parameters, and to improve the understanding of the relationships between deformation mechanism, structural position, lithology and the fracture systems. Ultimately, the aim of this study was to contribute to the generation of more realistic static geological models and dynamic reservoir simulation models.