CRUDE OIL GEOCHEMISTRY AND SOURCE ROCK POTENTIAL OF THE UPPER CRETACEOUS – EOCENE SUCCESSION IN THE BELAYIM OILFIELDS, CENTRAL GULF OF SUEZ, EGYPT
CRUDE OIL GEOCHEMISTRY AND SOURCE ROCK POTENTIAL OF THE UPPER CRETACEOUS – EOCENE SUCCESSION IN THE BELAYIM OILFIELDS, CENTRAL GULF OF SUEZ, EGYPT
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埃及苏伊士湾中部贝拉伊姆油田上白垩统始新世系列的原油地球化学和烃源岩潜力
DOI：
10.1111/jpg.12606
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发表时间：
2015
影响因子：
1.8
通讯作者：
K. Peters
中科院分区：
文献类型：
--
作者：
W. S. E. Diasty;S. E. Beialy;A. Mostafa;A. Ghonaim;K. Peters
本文对苏伊士盆地中部海湾Belayim油田裂谷前上白垩统—始新统地层烃源岩油气潜力进行了评价。对底比斯组、棕灰岩组和马图拉组的65块岩屑进行了有机地球化学和孢粉相研究。分析方法包括岩石热解、液相色谱、气相色谱和气相色谱-质谱。利用C7轻烃、稳定碳同位素和生物标志物特征对产井4个原油样品进行了表征。结果表明，烃源岩为海相碳酸盐岩，有机质以藻类和细菌为主，陆源输入极少，沉积条件为还原性。这一结论得到了正烷烃分布、原烷/植烷比、高藿烷和伽马蜡烷指数、高胆甾浓度、C30正丙基胆甾的存在和低二甾烷比的支持。根据Rock - Eval Tmax和生物标志物成熟度参数，烃源岩从未成熟到微成熟不等。分析的原油样品被解释为来自始新世底比斯组和上白垩统棕色灰岩的烃源岩层段。原油地球化学特征的相似性表明，烃源岩的有机相变化不大。
This study evaluates the petroleum potential of source rocks in the pre‐rift Upper Cretaceous – Eocene succession at the Belayim oilfields in the central Gulf of Suez Basin. Organic geochemical and palynofacies investigations were carried out on 65 cuttings samples collected from the Thebes, Brown Limestone and Matulla Formations. Analytical methods included Rock‐Eval pyrolysis, Liquid Chromatography, Gas Chromatography and Gas Chromatography – Mass Spectrometry. Four crude oil samples from producing wells were characterised using C7 light hydrocarbons, stable carbon isotopes and biomarker characteristics. The results showed that the studied source rocks are composed of marine carbonates with organic matter dominated by algae and bacteria with minimal terrigenous input, deposited under reducing conditions. This conclusion was supported by n‐alkane distributions, pristane/ phytane ratios, homohopane and gammacerane indices, high concentrations of cholestane, the presence of C30 n‐propylcholestanes, and low diasterane ratios. The source rocks ranged from immature to marginally mature based on the Rock‐Eval Tmax together with biomarker maturity parameters. The analysed crude oil samples are interpreted to have been derived from source rock intervals within the Eocene Thebes Formation and the Upper Cretaceous Brown Limestone. The similarity in the geochemical characteristics of the crude oils suggests that there was little variation in the organofacies of the source rocks from which they were derived.