白音都兰凹陷石油化探效果

凹陷内的水文钻孔—ZK5井(井深211．67m),发现总厚达70余米的油层,属白垩系巴彦花样(K₁b),以ZK5井为中心卫片上存在“色调异常晕圈”。地表土壤氯仿抽提物含量在卫片“色调异常晕圈”内外也有区别,大于50ppm的点基本上集中在卫片“色调异常晕圈”范围内。石油化探在凹陷内发现了四个异常,其中重烃和重烃/碳酸盐指标均形成环状异常(I号异常)位于卫片“色调异常晕圈”范围内,二者重合的较好,和钻探见油气层结果对应,说明白音都兰凹陷石油化探效果是好的。     

冶金化探的回顾与展望

回顾了冶金系统化探发展历程和取得的主要成果,对今后冶金化探的发展提出了展望与建议。     

福建省物探化探遥感成果回顾

福建物探、化探工作起步于２０世纪５０年代。近半个世纪以来,福建省地质工作者利用物探、化探、遥感等技术在区域地质,深部地质,矿产,水文、工程地质,环境,医学,农业地质等领域取得了丰硕成果,但还存在一定的差距。为进一步提高福建省物探、化探、遥感等技术水平和扩大应用领域,对今后工作提出几点建议和对策。     

“八五”计算机在物探化探中应用的回顾与展望

本文系统的介绍“八五”计算机在物探化探中的应用，并对“九五”计算机的应用进行了展望     

油气化探在石油普查勘探中的应用

70年代以来,一种新的勘探油气的经济、有效的方法——石油化探方法开始兴起。以吉林省延吉盆地和廊固凹陷的石油化探工作为例,阐述了石油化探在油气普查勘探中的作用,提出应采用地质、物探和化探相结合的方案,以提高勘探油气田的效率和效益。     

40年来物探,化探工作回顾

４０年来江苏省地矿厅的物,化探工作大致经历了４个阶段,即５０年代末至６０年代中期的以找铁为主的普查找矿阶段,６０年代中期至７０年代末以寻找铜及多金属矿为主的普查找矿阶段,７０年代末至９０年代物,化,遥技术全面发展和应用的阶段,９０年代初以来的调整和工程物探发展的阶段。     

油气化探方法在方正断陷油气勘探中的应用

方正断陷近地表油气地球化学勘探工作采用土壤酸解烃、蚀变碳酸盐(△C)和荧光光谱分析技术,筛选出多个反映油气异常的指标,圈定出红旗Ⅰ级综合异常、西六方Ⅱ级综合异常和宝兴Ⅲ级综合异常。红旗Ⅰ级综合异常和西六方Ⅱ级综合异常具有异常强度大、平均衬度和评价指数高等特征,为最有利含油气远景区,是进一步勘探的主要方向;而宝兴Ⅲ级综合异常强度弱,仅具一定的参考意义。方3井、方401井、方6井和方4井均部署在西六方Ⅱ级综合异常上,获得工业油气流,证实了异常下油气的存在。     

油气化探土壤样品解吸气技术实验研究

油气地球化学勘探中常用的顶空轻烃和物理吸附烃属于吸附态的烃类,两者在处理土壤样品时没有粉碎,使得吸附烃没有完全解吸. 油气化探土壤样品解吸气技术就是利用自行研制的油气化探原位土壤样品保存与解吸装置,通过实验选择加饱和盐水或纯净水,改变样品量、样品解吸时间、负压条件,从而确定解吸气提取的最佳实验条件,建立油气化探土壤样品解吸气提取的方法. 运用重复性对该方法进行评价,并选择富安油田试验区的一条已知地质剖面开展土壤中解吸烃指标的应用,研究结果表明,解吸气技术在油气藏上方具有较好的化探异常响应.     

Surface geochemical methods used for oil and gas prospecting — a review

The majority of the world's oil and gas deposits have been discovered by drilling in the vicinity of natural petroleum seeps, and to date the most successful geochemical prospecting methods still rely upon the surface detection of hydrocarbons. Gas chromatographic techniques are now commonly used in the analysis of hydrocarbon gases for prospecting both onshore (analysis of soils and rocks) and offshore (analysis of near-bottom waters and sediments). Detection of helium fluxes has been partially successful as a geochemical prospecting technique. Many indirect techniques such as the determination of isotope and metal-leaching anomalies in surface rocks and the measurement of radon fluxes have not been widely used.Onshore geochemical prospecting appears to have more problems associated with it than offshore prospecting due to the more complex migration mechanism of near-surface waters containing dissolved gases. No onshore prospecting studies have been published which thoroughly consider this factor and the success of onshore prospecting remains equivocal. In offshore prospecting “sniffers” have been used to detect hydrocarbon anomalies in near-bottom waters, and coring equipment has been used for the detection of hydrocarbons in near-surface sediments. Success is claimed using these techniques.Geochemical prospecting methods are complementary to the widely used geophysical methods. Geochemical methods can provide direct evidence for the presence of petroleum accumulations and are relatively cheap and rapid. Failures in prospecting to date are attributable to the simplistic manner in which data have been interpreted; insufficient attention has been paid to the hydrological and geological factors which modify the upward migration of indicator species to the surface. As oil and gas deposits become more difficult to locate, greater attention should be paid to geochemical prospecting techniques, especially as a regional exploration tool.     

本世纪初我国油气化探的发展方向

在油气化探工作中,稠环芳烃含量对区域油气异常有着重要的指示作用。对于稠环芳烃的测定,诸多前处理条件对稠环芳烃的提取效率有显著的影响。本文研究了油气化探样品振荡提取法的多种前处理条件（提取溶剂、样品粒径、振荡时间和静置时间、提取温度）对荧光强度测定结果的影响。实验结果表明,提取溶剂不同,测定结果存在较大差异,各提取溶剂的提取效率大小依次为：二氯甲烷>正己烷>乙酸乙酯>石油醚。综合考虑溶剂背景值对测定结果的影响,选择以正己烷为提取溶剂进行条件实验。在研究的粒径范围内,荧光强度随样品粒径的减小而增大,但粒径过小荧光强度反而降低,粒径在0.125~0.090 mm之间的样品荧光强度最高;荧光强度随着振荡时间和静置时间的增加而增强,其中静置时间的影响较大,静置9 h后荧光强度提高不显著;振荡时间的影响相对较小,振荡20 min后提取效率提高不显著;提取温度对荧光强度的影响最为显著,在相同条件下,提取温度越高荧光强度越大,且提取温度是影响稠环芳烃测定结果重现性的关键因素。油气化探样品前处理的最优化条件为：采用粒径在0.090~0.177 mm之间的样品,以色谱纯正己烷为溶剂,提取温度25℃,振荡时间20 min,静置时间12 h。     

油气化探异常预测油气藏埋藏深度探讨

通过对大庆油田丰富的地表油气化探、钻井资料分析研究,结合油藏放射性异常模型,提出了氡异常水平分布及特征值与油气藏深度的关系数学模型及参数计算方法。通过大庆油田杜29井区实际资料验证和平洋来27井区、来36井区试验应用,证实用地表油气化探特征值估算确定油气田埋藏深度的技术方法是可行、实用的。而这种解释结果结合地质解释分析,对指导油气田勘探部署,提高勘探效益都具有实际意义。     

四川盆地麻柳场以北地区油气化探应用效果

四川盆地蜀南地区就是一个典型油气田老区,在麻柳场气田以北地区开展油气化探工作,通过对各地层中烃类和非烃指标的研究并取得了很好的效果,对该地区下一步油气勘探部署提供了有力的地球化学依据。     

A review of indicator minerals and sample processing methods for geochemical exploration

Geochemical exploration based on the analysis of indicator minerals (IMs) is becoming increasingly used as an effective method for mineral exploration for many types of mineral deposits. The types of IMs used or recommended for exploration for different types of deposits, their properties suitable for concentrating them, as well as those of other common minerals from which they must be separated are listed.     

辽宁金羊盆地羊D1井油砂地球化学特征及意义

在中国地质调查局沈阳地质调查中心实施的"羊D1"井的中侏罗统髫髻山组火山岩中见多处油气显示,取得了油气新发现。对该井已发现的2件油砂样品中的原油采用气相色谱-质谱技术(GC-MS)进行了分析测试,结果显示,2个油砂样品的地球化学特征一致,表现为链烷烃呈现出单峰态的分布,主峰碳数分别为C_(21)和C_(22),无明显奇碳数优势,姥植比值低;萜类化合物表现为,三环萜烷以C_(23)为主峰呈正态分布,C_(24)四环萜烷与C_(26)三环萜烷丰度相当,伽马蜡烷含量较高;甾类化合物表现为规则甾烷相对含量关系为C_(27)C_(29)C_(28),以C_(27)甾烷占优势的不对称"V"形分布。这些指标总体指示,原油为成熟油,对应烃源岩沉积于偏还原性的湖相环境,母质来源主要为藻类等低等水生生物,陆源高等植物也具有一定贡献。通过和周边的北票组烃源岩进行油岩对比研究发现,油砂样品中的原油可能来自于盆地内下伏的下侏罗统北票组烃源岩的贡献。研究结果说明,北票组在金羊盆地分布广泛,其烃源岩可能具有较好的生油潜力,金羊盆地是一个具有勘探潜力的含油气盆地。     

西沙海槽研究区天然气水合物地球化学勘探及成藏模式研究

依据ODP204航次1250C站位钻井样品酸解烃数据结果,以及作者在南海西沙海槽研究区天然气水合物地球化学现场勘查中得到的多种烃类指标数据、异常点上微量甲烷碳同位素数值等资料,对海洋水合物地球化学勘探的依据和研究区气态烃异常特征、气体成因、天然气水合物成藏模式等相关问题进行了研究探讨。结果表明:气态烃指标地球化学异常主要分布在工区北部斜坡地带,并与BSR等地震标志及深部断裂关系密切;西沙海槽研究区海底沉积物气态烃甲烷以热解成因为主,但也有混合成因;推测该区天然气水合物为断层渗滤综合成藏模式。研究成果比较合理地解释了BSR分布和海底沉积物甲烷局部异常并非完全一致的原因;评价预测了该区天然气水合物有利勘探目标。成果为该区天然气水合物勘探、天然气水合物成因机制研究和天然气水合物远景预测,提供了地球化学方面的证据。     

Meteorological noise in crustal gas emission and relevance to geochemical exploration

The emission of gas from the earth's crust is a complex process influenced by meteorological and seasonal processes which must be understood for effective application of gas emission to geochemical exploration. Free mercury vapor emission and radon emanation are being measured in a shallow instrument vault at a single nonmineralized site in order to evaluate these influences on gas emission.Mercury concentrations in the instrument vault average 9.5 ng/m³ and range from < 1 ng/m³ to 53 ng/m³ with a strong seasonal effect. Mercury has a direct relationship to vault temperature, air temperature, soil temperature, barometric pressure, water table, and the frozen or thawed state of the soil. Air and soil temperature, barometric pressure, and relative humidity are most important in influencing mercury emission while soil moisture is also important in radon emanation. Diurnal cycles are common but do not occur on all days. A heavy precipitation event on a dry soil seals the soil resulting in a rise in mercury concentration. Precipitation on a soil that is already wet does not increase mercury emission because of the compensation caused by lowering of the soil temperature by the precipitation event. Freezing of the soil changes the physical state of the vault-soil-soil gas-atmosphere system and emits the lowest concentrations of mercury. Phase lag effects are likely important. Stepwise multiple regression of mercury as dependent variable with meteorological and seasonal parameters as independent variables gives a cumulative R value of 0.563 and R² of 0.317. The short-term noise coupled with phase lags are an important factor.The radon measurements integrated over weekly intervals smooth out much of the short-term noise. Stepwise multiple regression of radon as dependent variable with meteorological and seasonal parameters as independent variables gives a cumulative R value of 0.967 and R² of 0.934. In this portion of the study the variation in the radon emanation is adequately predicted by meteorological and seasonal parameters.