Lithofacies and diagenetic study of the Uthmaniyah Arab-D limestone member (Ghawar oil field)

(1992) Lithofacies and diagenetic study of the Uthmaniyah Arab-D limestone member (Ghawar oil field). Masters thesis, King Fahd University of Petroleum and Minerals.


Download (5MB) | Preview

Arabic Abstract


English Abstract

The cored, late Jurassic, Arab-D Limestone member in the two Uthmaniyah wells 587 and 628 has been studied. A total of 193 thin sections were prepared and examined for both its litho-and biofacies analysis as well as for the diagenetic study of the succession. Lithologically, the succession is divisible into six units that are worthy of sub-member rank. These correlated in the two wells using core descriptions, and well logs thin section analysis. Such analysis has also led to the recognition of two distinctive microfacies that are used to interpret both the age and the paleoenvironmental conditions of deposition of the succession. A rich assemblage of fossils has been recorded including: Textulariid, Miliolid, and Rotaliid (Foraminifrida), as well as abundant bryozoan, algal and corralline remains. Worthy of mention among these are Kurnubia spp, Nautiloculina spp, Pfendrina spp., andPsudocyclammina spp., Bramkampella spp., and Clypeina jurassica. These fossils suggest a Kimmeridgian-Tithonian age. The succession represents a shallowing upward carbonate cycle moving from open lagoons (at the base) to a shallow self lagoon, located in straits and bays behind the outer platform edge (at the top). The main diagenetic changes observed in the succession are limited to cementation, micritization, dolomitization and dissolution. Diagenetically the cementation and micritization are pore reducing, whereas dissolution and dolomitization are pore enlarging.

Item Type: Thesis (Masters)
Department: College of Petroleum Engineering and Geosciences > Geosciences
Committee Advisor: El-Naggar, Z. R.
Committee Members: Saner, Salih and Saif, Saiful-Islam
Depositing User: Mr. Admin Admin
Date Deposited: 22 Jun 2008 13:43
Last Modified: 02 Aug 2021 06:06