Isopach,lithofacies changes,and source rocks chracteristics of Khatatba and Alam El Bueib formations of some wells in North East Western Desert,Egypt

The present work deals with isopach, lithofacies changes, and source rock chracteristics of Khatatba and Alam El Bueib formations of some wells in North East Western Desert. Isopach and lithofacies changes showed that the thickness of Khatatba Formation increases toward the south western direction and decreases toward northern parts, and the sediments consisting of sandstone and shale facies indicate a shallow marine environment. Alam El-Bueib sediments increase toward the north direction, and argillaceous sandstone facies reflect terrestrial-to-shallow marine environment. The geochemical analysis showed that Khatatba Formation bears a mature source rock and has poor-to-good generating capability for both oil and gas and lie within the early generation window and oil window. Alam El Buieb Formation constitutes a mature source rock and has poor-to-good generating capability for both oil and gas. It can be stated that Khatatba and Alam El Buieb are the main source rock for hydrocarbon accumulations rich with organic sediments and could be considered as effective source rocks for generating hydrocarbons in the the studied wells.     

The Volumetric Calculation of Hydrocarbons Generation of Source Rocks in the Gulf of Suez,Egypt

Regression lines obtained from TOC versus S ₂ graphs of organic rich samples were collected from Rahmi, West Bakr, Ras Gharib, and Esh El Melleha wells in the Gulf of Suez. By applying the hydrogen index values obtained from S ₂ versus TOC graph and mass balance calculations obtained from the results of Rock-Eval pyrolysis, the original hydrocarbon generative capacity and the amounts of the hydrocarbons generated are estimated. Calculation results indicate that the amounts of original hydrocarbons and the hydrocarbon generative capacities of the two methods are similar and correlated with the results of the Rock-Eval pyrolysis. This indicates that such calculations can be applied in the hydrocarbons evaluation of source rocks.     

Bulk Geochemical Characteristics of Crude Oils From Wells in the North Western Desert,Egypt

Abstract

Different oil samples were collected from oil fields in the North Western Desert; namely, Meleiha, Razaak, and North Qarun fields. These oils were analyzed geochemically, including sulfur content, American Petroleum Institute (API) gravity, and gas chromatography The results showed that API gravity and sulfur content indicate that the crude oils have high mature level of marine origin. Distribution of n-alkanes (Carbon Preference Index [CPI], pr/ph, and isoprenoide/n-alkanes ratios) reflects that the oil samples originated mainly from marine organic sources deposited in a reducing environment. This indicates that the oil samples under investigation are well correlated with each other in the western part of the North Western Desert.     

Timing of petroleum generation and source maturity of selected wells in Abu Gharadig Basin,North Western Desert,Egypt

The timing of petroleum generation of source rocks is recognized to investigate the maturation level of the proven potential source formations for oil preservation dead lines, and predict the levels of thermal maturity of the studied sequences in terms of hydrocarbon generation and expulsion. For theses purposes four thermal burial history and maturity profiles were constructed of the Abu Gharaig-1 SW Umbaraka-1, GPZ-1, and GPX-1 wells. The results showed Abu Roash and Bahariya formations are immature to mature source rocks and have poor to fair potential to generate both oil and gas and still are within the early stage of hydrocarbon generation till the present time. Alam El Bueib and Masajid formations bear mature source rocks and have good generating capability for generating both oil and gas and entered the oil window since Cretaceous to Miocene times and lies within oil and gas windows at present time. Khatatba Formation bears a mature source rock and has good generating capability for both oil and gas and entered the oil window during Late Cretaceous to Eocene times.     

石英原料在太阳能产业及其他高科技工业中的应用前景——以哈萨克斯坦和埃及为例

人类开发应用石英具有悠久的历史:早在石器时代,人类就曾将石英作为装饰品、工具、法器、武器、日用品等应用;在工业时代,石英主要作为玻璃原料及冶金熔剂使用;当代,石英广泛应用于许多工业和高科技领域。近年来,石英作为可再生能源及其它高科技领域用的材料,特别是以石英为原料制备多晶硅及单晶硅作为微电子学材料及太阳能利用材料方面展示了广阔的前景。但这个领域对石英纯度的要求很高,通过传统的提纯和晶体生长技术将石英转化为硅很不经济,因为传统方法大量使用氯、氯化氢及四氯化硅对环境有负面影响。而开发闭路循环技术系统或使用高纯度石英原料是解决这个问题的重要途径,前者取决于化学冶金技术水平,而后者则取决于矿产地质。因此,高纯度石英的找矿评价及工业硅的提纯是大力发展太阳能产业的重要途径。目前,以石英为原料进行高纯半导体材料和微电子材料等的合成在有些国家已经大规模工业化,并形成产业,如太阳能产业和高科技工业。据预测,在2010至2012年间,高纯石英原料将会短缺且竞争激烈。根据发达国家的实践经验,在哈萨克斯坦建立用于太阳能和其它高科技工业的高纯石英基地具有重要的理论和现实意义。哈萨克斯坦高纯石英资源丰富,在哈萨克斯坦中部,变质成因的石英脉及交代型的石英岩很普通,在东部、中部、南部和西部,石英结晶花岗岩则很多,水晶矿床则主要集中在哈萨克斯坦的西南地区,花岗岩侵入体的水晶矿以及粒状石英脉几乎在哈萨克斯坦到处都有分布,结晶花岗岩则分布在哈萨克斯坦北部和南部地区,但是该国针对高纯石英的工业化研究与应用则很少。埃及的石英原料也很丰富,主要矿床位于该国中部和东南部地区,工业化研究与应用也很少。建议这两个国家将高纯石英原料作为太阳能产业及其它高科技产业发展的重点研究领域。     

埃及西沙漠盆地中生界烃源岩特征及剩余资源分布

西沙漠盆地是埃及三大主要含油气区之一,已发现大量的油气田,现处勘探发现中期,预探风险增大。为此,在详细评价盆地烃源岩地球化学特征基础上,运用盆地数值模拟技术定量分析剩余资源潜力。研究认为,中侏罗统Khatatba组Safa段和Zahra段煤系暗色泥页岩以及上白垩统Abu Roash组AR-F段暗色泥页岩是盆地的3套主力烃源岩,各凹陷烃源岩广泛分布,厚度变化较大。Khatatba组烃源岩TOC含量在0.5%~10%,裂解烃S₂含量高,为中等-很好烃源岩;Abu Roash组AR-F段烃源岩TOC主要在0.5%~3%,裂解烃S₂含量中-高,属中等-好烃源岩。这3套烃源岩有机质干酪根类型以混合Ⅱ型为主,其次是Ⅲ型,少量为Ⅰ型。指出Khatatba组2套烃源岩全盆处于热演化成熟大量生排烃阶段,凹陷中心达高熟生烃、局部过熟生气阶段,油气并生;Abu Roash组AR-F段烃源岩仅Abu Gharadig和Natrun凹陷进入成熟生烃阶段。提出盆地北部地区主要由侏罗系Khatatba组烃源岩供给油气,东南部地区则有侏罗系Khatatba组和白垩系AR-F段双源供烃。计算表明,盆地剩余可采资源量达6.51×10⁸ t,剩余资源潜力很好;其中,南部Abu Gharadig凹陷古生界、侏罗系和下白垩统AEB,北部Matruh凹陷古生界、Faghur凹陷上白垩统,油气探明程度低,剩余资源可观,为下步勘探的有利方向。     

API gravities,vanadium, nickel,sulfur, and their relation to gross composition: Implications for the origin and maturation of crude oils in Western Desert,Egypt

In the present study, the geochemical analyses of API gravities, vanadium, nickel, sulfur, and bulk composition were performed on eight samples from productive wells in Gindi, South Deep Abu-gharadig, Abu-gharadig, Dahab-Merier, and Faghure basins locates in the North Western Desert. The results were used to describe the source organic matter input, depositional environment, assess the degree of thermal maturity, and to correlate between crude oils to determine the genetic relationship between hydrocarbon generation and their source rock for the studied oil samples. The results showed that a wide range of crude oil parameters exists in this data, indicating that a variety of oil types is represented. Crude oils range from unaltered to altered by vanadium, nickel, and sulfur concentrations, V/Ni and saturate fraction were used to classify the oils. Oils are classified into two groups. Group I contains oil samples from Gindi, South deep Abu-gharadig and Abu-gharadig, and Dahab-Merier that are generated from organic matter input deposited in marine environment under anoxic to suboxic conditions. Group II from Faghur basin possess high Pr/Ph ratios suggesting high contribution of terreginous organic matter deposited under relatively oxic conditions.     

Source input and maturation assessments of oil families depending on specific and gross geochemical aspects of crude oils from Bakr oilfields in the central Gulf of Suez,Egypt

Different analytical techniques, including API gravity; sulfur–nickel–vanadium contents; liquid chromatographic separation; and gas chromatography, were utilized to investigate oil families of three crude oils collected from Bakr oilfield of middle-lower Miocene age and characterized by limestone facies at various depth locations in the central Gulf of Suez. These geochemical aspects were used to assess source input and maturation of oil families. The results showed that the studied oils indicate a close genetic relationship between studied crude oils, and classified as aromatic intermediate oils. These types of oils are characterized by mature sources derived mainly from marine inputs such as biomass from algae and plankton from different saline environments.     

Oil-source rock correlations of Jurassic and Cretaceous oils in the West Khalda area,North Western Desert,Egypt

Oil-source rock correlations are used in this study in order to achieve their relationship, depositional environments, and diagenetic processes in the source rocks. For this purpose many parameters are used, e.g., gross composition of oil and source rock extracts, and biomarker analyses. Ten representative oil samples and seven source rock hydrocarbon extracts were analyzed using relative geochemical analyses, and gas chromatography-mass spectrometry. The results revealed a genetic close relation between them and supported the indigenous mixed source of Alam El Bueib oil, which related to different sources, including Khatatba, Alam El Bueib, and Bahariya formations. Accordingly, Alam El Bueib formation can be considered as an important source for petroleum generation in that area.