Fault
and Fractures within Jurassic Petroleum
System in Kuwait, with Special Reference to Hydrocarbon Habitat
By
Salah Abdulla AbdulMalek1, Sunil Kumar Singh1, Fahed Al-Medhadi1, Ahmad Jaber Al-Eidan1, Nikhil Chandra Banik1, Abdulaziz Sager Al-Anezi1
(1) Kuwait Oil Company, Ahmadi, Kuwait
This paper is representing an ongoing study for fault
and fracture systems
within Jurassic Petroleum System in Kuwait. The study aims at detailed
description of faults and fracture systems and discusses the specific
characteristics of these. So far the Structural elements of Jurassic Formations
were inferred on the basis of gravity, magnetic and old vintage regional 2D
seismic data.
The newly acquired high quality seismic data (2D and 3D) coupled with wealth
of information in the form of core, thin section, image log and specially
designed VSP data from drilled wells form the basic ingredients for this study.
These have been integrated with regional stress regime. This has resulted in the
understanding of fault
and fracture systems from regional to microscopic scale.
The key controls for faults and fractures were established. The faults have been
categorized on the basis of genesis, age, reactivation history, trends, extent
and throw etc. Image log data and seismic attribute (coherency, Edge detection,
etc) have been used to decipher sub seismic faults and associated fracture
systems.
An attempt has been made to see the relationship with oil habitat. The
fracture systems associated with certain fault
trends have facilitated the flow
of Jurassic reservoirs while the others played a key role in
compartmentalization of these reservoirs. The reactivation of Jurassic faults
affected the seal integrity of Gotnia Formation at few places, laterally as well
as vertically. The positive influence of reactivation had been on fracturing,
which is key for Najmah/Sargelu reservoir productivity. While
Fault
related
digenesis have adversely affected the reservoir properties of nearby wells.