SOURCE ROCK EVALUATION AND GEOCHEMISTRY OF CONDENSATES AND NATURAL GASES, OFFSHORE NILE DELTA, EGYPT
Author:
- 1 April 2003
- journal article
- Published by Wiley in Journal of Petroleum Geology
- Vol. 26 (2) , 189-209
Abstract
Geochemical analyses of mudstones from wells in the NE offshore Nile Delta suggest that the Early Miocene Qantara Formation has “good” potential to generate hydrocarbons at the studied locations. Its generating capability and oil‐proneness increase northwards, towards areas where better organic‐matter preservation and a greater contribution from marine source material can be expected. By contrast, the Middle Miocene Sidi Salem Formation has “poor to fair” potential to generate mixed gas and oil, while the overlying Wakar and Kafr El Sheikh Formations have “poor” capability to generate gas with minor oil. Based on pyrolysis Tmax and thermal alteration index assessments, the Wakar and Kafr El Sheikh Formations are immature in the study area. The Sidi Salem and Qantara Formations are immature in the southern part of the study area, but are within the oil window in the north, around well Temsah‐4.Biomarker distributions based on GC‐MS analyses of two condensate samples from the Wakar and Sidi Salem Formations indicate that hydrocarbons are derived from siliciclastic source rocks containing significant terrestrial material and limited marine organic matter. The condensates were generated during early maturation of Type III kerogen from deeper and more mature source rocks than those encountered in the drilled wells. Geochemical and isotopic data from natural gas produced from the Kafr El Sheikh Formation suggest mixed biogenic and thermogenic sources.Keywords
This publication has 26 references indexed in Scilit:
- THE NATURE AND ORIGIN OF PETROLEUM IN THE CHAIWOPU SUB‐BASIN (JUNGGAR BASIN), NW CHINAJournal of Petroleum Geology, 2000
- Empirical carbon isotope/maturity relationships for gases from algal kerogens and terrigenous organic matter, based on dry, open-system pyrolysisOrganic Geochemistry, 1996
- Origins, characteristics, controls, and economic viabilities of deep-basin gas resourcesChemical Geology, 1995
- Genetic and post-genetic molecular and isotopic fractionations in natural gasesChemical Geology, 1995
- Biomarker and n-alkane isotope profiles for Tertiary oils: relationship to source rock depositional settingOrganic Geochemistry, 1994
- Biomarker maturity parameters for high maturities: Calibration of the working range up to the oil/condensate thresholdOrganic Geochemistry, 1990
- Organic-geochemical characterisation of sediments from the Sakoa coalfield, MadagascarOrganic Geochemistry, 1990
- Geochemical and biological marker assessment of depositional environments using Brazilian offshore oilsMarine and Petroleum Geology, 1988
- Geochemical application of sterane and triterpane biomarkers to a description of oils from the Taranaki Basin in New ZealandOrganic Geochemistry, 1988
- Correlation of the Canol Formation source rock with oil from Norman WellsOrganic Geochemistry, 1987