Stratigraphy,Petrography, and Petrophysical Properties of the Subsurface Upper Cretaceous Sediments,Northwestern Desert,Egypt

Abstract

In this article, 33 core samples and 160 ditch samples of Upper Cretaceous age were studied at different depths from Horus well 1. Stratigraphic, petrographic, and petrophysical studies and well log analysis are used to study and evaluate the rock units. The studied core samples are dolomite (Abu Roash formation), shaly limestone, and argillaceous sandstone (Bahariya formation). The depositional environments of the studied rock units vary from deltaic to deltaic-marine. The effective porosity of the studied core samples is low and may be of secondary origin. The upper part of low Bahariya is considered a high category of reservoir. The stratigraphic significance of some benthonic foraminifera (Thomasinella, Nezzazata, and Nezzatine) furnishes new information on the age determination. Cenomanian-Santonian time is suggested for the studied interval (Bahariya and Abu Roash formations).