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101.
通过对新疆塔里木盆地北缘油气谱的实测和分析,结合烃类微渗漏理论,讨论油气信息的波谱特征和遥感直接探测的机理。运用遥感技术探测油气信息,一是探测烃类微渗漏产生的地表理化异常,二是直接探测渗漏运移到地表的烃类物质或土壤吸烃信息。在塔北试验区,烃类组分异常是最直接,最有意义的标志,2.32-2.36μm的烃类吸收双谷位置,被确定为塔北地区油气遥感探测波段。 相似文献
102.
地下深处的油气藏中的烃类物质,在压力梯度下会向地表产生微渗漏,导致地表物质产生一系列理化异常,在地表形成吸附烃异常、红层退色、粘土化、碳酸盐化、放射性异常和地植物异常等标志。根据这些地表标志的地物波谱特征,选择出油气资源遥感勘查的最佳工作波段,在此基础上,以机载遥感信息为主,以星载遥感信息为辅,以地表地球化学、地植物学、地面遥感勘查作为验证手段,最终施行多元信息复合分析,可达到寻找油气藏的目的。 相似文献
103.
104.
四川威远气田烃流体包裹体的研究 总被引:3,自引:0,他引:3
通过烃流体包裹体的类型、均一化温度、气相及液相成分、盐度以及同位素的研究,可以认为威远气田的天然气主要是由白云岩中有机质形成。由于从80~160℃到200~240℃的热解作用,有机物质已演化到过成热阶段。这一过程可由白云岩中存在液态烃及含沥青烃流体包裹体得到证明。威远气田的特征是:震旦系白云岩中天然气的自产自储,以CH_4为主;油田水为古海水,盐度(4.3~17.2)wt%NaCl,pH>8,(CO+CH_4)/CO_2比值指示还原条件。在基底花岗岩石英中发现有气态烃包裹体,其成分及δ~(13)C‰与花岗岩储气层中产出的天然气一致,为部分天然气可能来自深部地壳或地幔提供了新的证据。因而,威远气田天然气的成因主要由有机物质形成,部分甲烷气可能经基底断裂来自地球深处。 相似文献
105.
Data from the super-deep wells(PS10,PS14 and YS1)led to the discovery of widespread met-al-bearing hydrothermal fluids (or hot brines) related to basic magmas in the Lower Tertiary clastic sequence in the Dongpu Depression .In terms of SEM and EDAX analyses, pore-casting thin section examination of sandstone ,the composition and forming temperature of fluid inclusions ,the trace ele-ment composition of mustone and kerogen and organic geochemical analyses, it is demonstrated that the hydrothermal fluids existing in the area studied are ejecting fluids, which have a close bearing on diagenesis and sedimentation, rather than intrusive veins along the tectonic fractures.The main indicators of hydrothermal activity are:(1)abnormal alteration of kerogen;(2) high-temperature altered mineral assemblage;(30abnormal distribution of hydrocarbons;(4) specific assemblages and abnormal contents of heavy metals in mudstone and kerogen;(5) specific composi-tion of complex compounds and assemblages of fluid inclusions in sandstone;(6) periodic basaltic magma activity.Results of geological observations and laboratory simulating experiments demonstrated that the hydrothermal fluids have a close bearing on hydrocarbon generation in the Dongpu Depression. Two aspects of the effect of hydrothermal fluids are noticed:hydrothermal hydrocarbon production and strong metal catalysis in oil and gas generation. 相似文献
106.
本矿物为新发现的钇易解石族的端员矿物-钛钇易解石,产于江西省龙南县足洞燕山期中粒白云母花岗岩及其风化壳中。矿物属斜方晶系,常呈板状或短柱状,为天然晶质体,浅黄色,粒度为0.075mm,硬度4.7,比重4.73,二轴正晶,Ng=2.248,Nm=2.212,Np=2.194,Ng-Np=0.054,2V=70°。空间群为D^162h-Pmnb,a0=0.750nm,b0=1.092nm,C0=0.5 相似文献
107.
Six North American bituminous coals (four Carboniferous and two Cretaceous) and eight maceral concentrates from Carboniferous British seams have been heated with tetralin and hydrogen to 400°C. The hexane-soluble parts of the products were separated by column chromatography and the fractions were then analyzed by gas chromatography/mass spectrometry. In all cases the aromatic hydrocarbon fraction was a very complex mixture containing a number of alkylated biphenyls, diphenylmethanes and -ethanes, and polycyclic compounds. However single ioncchromatography (m/z = 142) showed that, in addition to these, the products from five of the six American coals contained homologous series of long chain n-alkylnapththalenes with alkyl groups extending to C16. In other fractions from the American coals, homologous series of n-alkylfurans and alkylphenols were found to be major components, as also were many alkylcyclohexenones related to isophorone. Extensive homologous series of n-alkyl aromatics were not detected in products from any of six vitrinites from British seams, though series of n- and iso-alkylphenols were found in the products from two sporinite concentrates. A number of polycyclic ketones apparently related to sterols were found in the products from the British vitrinites but not from any American coals. Reasons for what appear to be systematic structural differences between the American and British coals are discussed. Differences in stratigraphy are noted and it seems not impossible that differences in source vegetation are significant. 相似文献
108.
An infrared routine has been developed to estimate the aliphatic portion of kerogen carbon in sedimentary rocks. The procedure does not require isolation of the organic matter and is based on a computer-assisted determination of global band areas in the region of the aliphatic carbon-hydrogen stretching vibrations around 2900cm−1. From these integrated absorptions the amount of aliphatic carbon Cal (mg of aliphatic carbon per gram of solvent-extracted rock) is calculated by means of a calibration with model rocks. Carbonate overtones which interfere in the case of limestones are eliminated by comparison to a CaCO3 standard.The method has been applied to rocks containing kerogens of different types and maturities at TOC levels of 0.5 to 12%. The aliphatic carbon concentrations range from 0.5 to 60mg·g−1 and correlate reasonably well with the residual genetic potentials of the rocks as measured by S2 values from Rock-Eval pyrolysis. The ratio S2/Cal is found to decrease with burial depth reflecting a maturity enhanced conversion of aliphatic carbon to fixed aromatic carbon under Rock-Eval conditions. 相似文献
109.
长春市北西或北北西向扭性断裂或断裂带是客观存在,它对长春市深部地下水循环与循存起控制作用,是深部基岩裂隙水的主要导水通道,且大都为富水带。原北东向压扭性断裂或断裂带起阻水作用,二者相得益彰。笔者于长春北郊贫水区,利用这一新理论,在水文地质调查基础上,结合多种水文物探手段布孔凿井,打出一口水量丰富的优质矿泉水井,进而验证了北西向富水说,了箕市深部地下水赋存规律的新认识,此说不但对长春市供水有实际意义 相似文献
110.