黄骅坳陷孔西潜山下古生界原生油

华北地区经历过晚奥陶世至泥盆纪长达１３０Ｍａ的沉积间断，分布于该地区的稳定而厚度很大的大下古生界碳酸盐岩能否二次生烃，形成下古是自生自储的原生油气藏，是有关华北地区下古生界油气勘探前景的重大问题。     

华北区古生界原生油气藏勘探前景

从油气系统角度分析了华北区古生界的石油地质条件。下古生界是一套以海相碳酸盐岩为主的沉积,在开阔海台地相的台凹环境下形成的源岩生烃潜力最大,纵向上表现为寒武系的府君山组、张夏组,奥陶系的马家沟组、峰峰组。平面上以黄骅—临清复向斜带为最有利区。上古生界是一套海陆交互相的煤系地层,煤层及暗色泥岩厚,热演化程度大多处于成熟—高熟阶段,生烃潜力大。从源岩的生烃演化史及油气的运聚和圈闭关系指出古生界具有形成原生油气藏的条件,原生油气藏勘探研究的难点及关键问题在于烃源岩的二次生烃潜力、范围及油气保存条件。在系统分析总结前人勘探研究工作的基础上,研究了渤海湾、南华北及沁水地区古生界油气生成、保存条件,指出渤海湾地区是二次生烃的最有利地区,油气保存条件好,古生界原生油气藏勘探前景广阔;南华北地区油气生成及保存条件好,但源岩演化程度较高,是天然气的有利勘探区;沁水地区亦具有二次生烃条件,但盖层及油气保存条件差、水动力条件强,北部地区古生界原生油气藏的勘探前景尚好。     

孔西潜山奥陶系原生油藏成藏时期探讨

黄骅坳陷孔西潜山发现奥陶系（孔古3井、孔古7井）低产原生油藏和石炭-二叠系原生油气藏（孔古4井），油源对比结果证明，前者原油主要源于中奥陶统马家沟组灰岩，后者油气主要源于石炭系太原组及二叠系山西组煤系泥岩。根据孔古3井油藏的两期流体包裹体及储集层自生伊利石K-Ar年龄测定结果，油藏属两期成藏，第一期为晚三叠世（距今222.51～240.34Ma），第二期为第三纪，以晚第三纪为主。     

下扬子区古生界油气地质条件及勘探选区

下扬子区发育海相上震旦统至上奥陶统烃源岩（大部分已进入过成熟干气阶段，经历过两期生油过程，仍有一定生烃能力）和上石炭统至二叠系烃源岩（其本处于生油晚期阶段）；成岩后生作用大大改善了古生界碳酸盐岩及碎屑岩的储集性能和渗滤性；古生界露头区已发现背斜逾２００个（许多面积大于４０ｋｍ２），预计覆盖区构造型及其它类型圈闭同样很多，具有优越的圈闭条件；广泛分布３套有效区域盖层（下志留统高家边组，上二叠统龙潭组，上白垩统浦口组），以浦口组盖层最重要。下扬子区上震旦统至二叠系的油气显示（油、气和固体沥青）多达４２４处，多赋存于洞、缝，反映该区经历过广泛的成油过程。印支期至燕山期的构造运动对古生界原生油气藏改造相当严重，但构造相对稳定的区块仍有勘探远景，综合分析认为，泰州—泰兴、南通—无锡、句容—南陵、射阳—大丰和无为—望江地区最有勘探前景。图３表２参４（王孝陵摘）     

沧县隆起地区古生界油气远景评价

沧县隆起地区早古生代盆地原型的一级构造单元为宽城－蓟县坳陷和德州隆起，晚古生代盆地原型的一级构造单元有苏桥坳陷，塘沽隆起和泊头坳陷。该地区奥陶系和石炭－二叠系有机质丰度均达到好或较好烃源岩的标准。奥陶系碳酸盐央为以生油为主的烃源岩，石炭系煤层和泥质岩为以生气为主的烃源岩，根据中，新生代构造运动对古生代盆地的改造程序及古生代烃源岩现今所处演化阶段，可将该地区古生界划分为改造－破坏型、改造－保存型和发     

MODELLING HYDROCARBON GENERATION IN THE PALAEOZOIC AND MESOZOIC SUCCESSIONS IN SE POLAND AND WEST UKRAINE

The Lower Palaeozoic succession in SE Poland and West Ukraine has source rock potential, particularly the Ordovician and Silurian which contain oil‐prone Type II kerogen. The thermal maturity of these units ranges from early to late‐phase oil window (locally up to gas window). Within the Mesozoic succession, source rock potential is highest in the Middle Jurassic which has TOC of up to 26 wt% and a genetic potential of up to 39 mg/g of rock, with organic matter dominated by gas‐prone Type III kerogen. In SE Poland, the organic matter in this unit is generally immature, whereas maturities in West Ukraine are sufficient for hydrocarbon generation to occur. Modelling of hydrocarbon generation suggested that petroleum in Lower Palaeozoic source rocks began to be generated in the Early Carboniferous. Peak generation took place from the late Visean to the early Namurian, and terminated either as a result of source rock depletion or Variscian inversion. Expelled hydrocarbons migrated during post‐Carboniferous and Mesozoic uplift. Middle Jurassic source rocks in SE Poland have only reached the early oil window. Higher thermal maturities in the Ukraine resulted in hydrocarbon generation and expulsion. This took place after Miocene burial and maturation. A number of small hydrocarbon accumulations occur in Mesozoic reservoirs in SE Poland / West Ukraine, and hydrocarbons have migrated from Cambrian and Ordovician source rocks. However, the prospectivity of the study area is reduced as a result of phases of uplift and intense erosion which allowed hydrocarbons to escape from structural traps.     

塔里木盆地顺北油田油气来源研究

基于塔里木盆地顺北地区原油和天然气样品的地球化学特征分析,研究了顺北地区奥陶系中下统油气来源。通过饱和烃色谱及饱和烃、芳烃色谱—质谱、全油及族组分碳同位素检测,发现原油样品中C23三环萜烷占优势,伽马蜡烷含量低,C27-C28-C29ααα20R规则甾烷表现为不规则的"V"字形分布,规则甾烷相对重排甾烷含量高,原油碳同位素偏轻,与柯坪露头及孔探1井等下寒武统烃源岩有很好的亲缘性;天然气δ13C1值为-50.7‰^-44.7‰,天然气δ13C2值为-36.1‰^-33.1‰,干燥系数为0.520~0.883,为原油伴生气,油气同源,判断顺北油田油气主要来源于下寒武统烃源岩。通过已钻井岩相、沉积相和全盆地地震相资料,预测下寒武统烃源岩在塔里木盆地广泛分布,厚度在30 m左右,有机碳含量高,生烃潜力大,具有长期生烃、多期供烃的特点,能提供充足的油气资源,是塔里木盆地台盆区最主要的烃源岩。     

遵义后坝奥陶系红花园组油苗岩石轻烃特征分析

遵义后坝奥陶系红花园组生物碎屑灰岩中发现油苗和沥青,经过气/源岩、沥青/源岩对比,震旦、寒武及奥陶系产层轻烃C₆₊₇结构组成基本一致,奥陶系含油苗灰岩轻烃星图与震旦系泥岩、寒武系沥青砂岩星图较为相似,显示红花园组油苗主要来源于震旦系和下古生界过成熟或高成熟海相烃源岩,油气经历了较长距离的运移,得以在奥陶系中保存下来。这对评价该地区油气前景有重要意义,预示着可能存在一套特殊的含油气组合,存在以O₁h古风化壳储集层为目的层的勘探领域。在兴文—叙永一线以西地区现今下古生界储盖组合保存良好,在适当的构造圈闭中可形成油气藏。志留系和二叠系产层轻烃C₆₊₇与震旦系、寒武系及奥陶系等产层轻烃C₆₊₇明显有别,星图对比性差,表征它们之间成烃母质或沉积环境均有不同。      

黄骅坳陷孔西地区油气的地球化学特征及油源初探

黄骅坳陷孔西地区孔古3井奥陶系地层及孔古4井中生界地层相继获工业性油气流,是几十年来华北地区古生界油气藏工业性勘探的首次突破,揭示出在黄骅坳陷以及华北地区古生界油气藏具有良好的勘探前景.通过对这两口井原油物性、地化特征的系统研究及与煤系烃源岩的综合对比分析,认为该区存在着两类原油,反映其油源来自不同母源,首次阐明该区奥陶系原油为低凝重质成熟原油,与古生界烃源岩具有成因上的联系,属原生油藏;而中生界原油为低凝轻质成熟原油,原油伴生天然气为煤型气,与上古生界煤岩有成因上的联系,属煤成油气藏.研究表明,这两类油藏的形成与其古压今张、古高今低的反转构造背景密切相关,印支-燕山期的挤压逆冲作用是油气成藏的关键.     

塔里木盆地海相油气成藏研究进展

近年来塔里木盆地超深层海相油气勘探取得了丰硕成果,顺北奥陶系、塔中寒武系、塔河深层等油气新发现,为塔里木盆地海相油气成藏研究提供了丰富的基础资料。塔里木盆地海相油气主要分布于台盆区,油气藏类型多样,原油物性变化大,显示出成藏的复杂性。通过对大量的实际样品分析和模拟实验及大量的地质、地球化学综合分析,结合构造演化、层序地层学、沉积相与沉积环境等研究成果,在烃源岩分布及其演化、油气地球化学特征、海相油气藏分布特征等方面取得了显著进展。一是明确了塔里木台盆区海相油气主要来源于强还原环境下形成的下寒武统-中下奥陶统烃源岩,特别是台盆区下寒武统玉尔吐斯组,并明确了超深层海相油藏后生改造主要有TSR、热裂解2种类型,提出了相应的判识指标;二是在建立玉尔吐斯组缓坡型优质烃源岩沉积发育模式的基础上,通过井震标定、正演模拟和区域测线地震相解释、三维区属性分析与地震反演,预测了玉尔吐斯组烃源岩的展布,并明确其演化特征:燕山期以来长期低地温背景下的"高压生烃演化抑制模式"延缓了顺托果勒低隆寒武系烃源岩热演化,顺托果勒地区仍具晚期高成熟液态烃形成条件;三是通过台盆区油气成藏特征对比,明确了奥陶系油气分布特征,进一步明确在台盆区寻找以下寒武统玉尔吐斯组原地烃源岩与燕山期以来晚期活动走滑断裂相匹配的、以晚期供烃为主的轻质油藏-天然气藏,是塔里木台盆区超深层碳酸盐岩领域油气勘探的重要方向。      

HYDROCARBON SOURCE ROCKS AND GENERATION HISTORY IN THE LUNNAN OILFIELD AREA, NORTHERN TARIM BASIN (NW CHINA)

In this paper we report on source rocks and maturation history at the Lunnan oilfield, northern Tarim Basin (NW China), using a combination of organic petrographic and geochemical techniques. Three separate source rock intervals are present here: Cambrian mudstones and argillaceous limestones; Middle and Upper Ordovician argillaceous limestones; and Triassic mudstones. Reservoir rocks comprise Lower Ordovician carbonates, Carboniferous sandstones, and Triassic and Jurassic sandstones. Structural traps were formed principally during the Silurian and Jurassic.
The Lunnan field is located on a small-scale palaeo uplift which developed during the Early Palaeozoic. Hydrocarbons migrated updip from source areas in surrounding palaeo-lows along faults and unconformities. Major phases of hydrocarbon generation and migration occurred in the Early Silurian — Late Devonian, Cretaceous — Early Tertiary and Late Tertiary. Uplift and intense erosion at the end of the Devonian destroyed Early Palaeozoic oil and gas accumulations sourced from the Cambrian source rocks, but hydrocarbons generated by Middle and Upper Ordovician source rocks during the Mesozoic and Tertiary have been preserved. At the present day, accumulations are characterized by a range of crude oil compositions because source rocks from different source areas with different maturation histories are involved.     

塔中地区油气源及成藏时期研究

塔里木盆地塔中地区已发现油气藏的油气源多且多期成藏，油气藏类型也很复杂，油源对比和研究油气藏形成时期对勘探有重要指导意义。综合应用全烃地球化学方法（油气碳同位素，油岩轻烃，油岩生物标志化合物），逐步判识塔中地区油气源，确认主力烃源岩为寒武系和奥陶系的碳酸盐岩（其中的泥质灰岩评价为较有利烃源岩），存在两大成因类型油气，即高成熟早期海相有机质成因油（寒武系至下奥陶统烃源岩）和高成熟湿气（中、上奥陶统烃源岩）。在此基础上，利用储集层有机包裹体均一温度分析和排烃史模拟计算结果，认为塔中地区有３期排烃高峰及成藏期，第一期主要为中奥陶世至志留纪（加里东期），第二期为二叠纪至三叠纪，第三期为白垩纪至现今（喜山期）。高成熟湿气喜山期侵入原生残留油藏有一定普遍性，可改造稠油、软沥青，使这类油藏仍有潜在勘探前景。图３表２参４（王孝陵摘）     

Cambrian crude oil in ZS well field,Tazhong area: characteristics,genesis, and comparison with ordovician crude oil

In this paper, the Cambrian crude oil and source-rock geochemistry in the ZS well field of Tazhong area, Tarim Basin, was analyzed using the gas chromatography-mass spectrometry (GC-MC). Moreover, the hydrocarbon source in the Tazhong was identified through oil–source correlation. The analysis of light hydrocarbons and biomarkers indicates that the Cambrian and Ordovician protokerogens are of marine sapropelic type formed in a strongly reducing environment. The result of oil–source correlation shows that both Cambrian crude oil in the ZS well field and Ordovician crude oil in the Tazhong area originated in the Cambrian–Lower Ordovician source rocks.     

贵州凯里地区下古生界原油油源分析

在分析贵州凯里地区及邻区古生界烃源岩特征基础上,重点分析了凯里地区下古生界原油地球化学特征。研究表明,凯里地区下古生界原油、油砂的碳同位素组成特征与下古生界烃源岩抽提物碳同位素组成较为接近,而与二叠系烃源岩抽提物的差异较大,反映原油与下古生界亲缘关系较好。但原油、油砂在规则甾烷组成特征、四环萜烷相对含量、γ蜡烷指数等生标特征参数上,却与二叠系烃源岩更为相似,表明研究区下古生界原油、油砂中的石油可能为下古生界烃源岩和二叠系烃源岩生成油的混源油;结合研究区及邻区构造—沉积演化史、烃源岩生烃演化史探讨了混源油形成的地质过程。      

塔里木盆地古生界的含油气前景

新疆塔里木盆地广泛发育着地台型古生界海相碳酸盐岩和碎屑岩,展布面积达六十多万平方公里,其中被掩埋于中、新生界之下者约五十万平方公里。据物探资料估计,在覆盖区内古生界的总厚度大约为4000—6000米,其埋藏深度为1000—10000米。由于在露头区发现了大量的油气显示,因此古生界的含油气前景引起了人们的广泛关注。但是目前古生界的调查研究程度甚低。对这个尚待开拓的找油领域,我们仅依据新疆地质局、新疆石油局和地质部航空物探大队的资料以及我们的实际资料,提出一些粗浅的看法。     

松潘-阿坝地区下古生界烃源岩评价

松潘-阿坝地区是油气勘探新区.该文对该地区下古生界露头剖面样品进行了有机碳分析,并结合烃源岩有机质丰度进行研究,对松潘-阿坝地区下古生界烃源岩进行了评价.作者认为,寒武系为潜在的好-很好烃源岩;奥陶系属潜在的差-中等烃源岩;志留系为潜在的中等-好烃源岩.     

鄂尔多斯盆地靖西地区奥陶系中组合天然气成因与成藏主控因素

鄂尔多斯盆地靖边气田扩边勘探过程中,在靖西地区下古生界奥陶系中组合白云岩储层中发现了多个含气区,但各含气区及各含气层段天然气的富集程度差异明显,目前尚不清楚造成上述差异的原因。为此,依据天然气组分、碳同位素值等地球化学资料,对比分析了该区奥陶系中组合天然气的成因·与来源,并研究了天然气成藏的主控因素。结果表明:①该区奥陶系中组合天然气与奥陶系上组合、上古生界天然气的成因与来源相似,均以上古生界生成的煤型气为主,但混有一定量的油型气;②受煤系烃源岩生烃中心和源储接触关系的影响,平面上由北向南、纵向上从下奥陶统马家沟组马五_(10)亚段到马五_5亚段,煤型气所占比例依次增大。结论认为,靖西地区奥陶系中组合天然气成藏主要受控于以下因素:①供烃窗口处天然气的充注能力决定了天然气的富集程度;②马五_5—马五_(10)亚段输导通道的差异控制了天然气的纵向运移及分布:③构造与储层叠合关系控制了天然气的横向运移方向及成藏范围。     

上扬子东南缘下组合优质烃源岩发育及生烃潜力

湘鄂地区海相下组合具良好的油气勘探前景,但地质条件复杂,勘探程度低.咸丰、大庸地区可能烃源岩的系统观测和有机地化剖面研究显示,下寒武统、上奥陶统五峰组—下志留统龙马溪组底部均发育一套黑色页岩,其有机质丰度高,总有机碳含量普遍大于1%;属藻腐泥型,生烃潜力高;具一定规模,厚度达数十米至百余米,分布稳定;有良好的生烃和油气显示,是2套优质烃源岩.晚侏罗世—白垩纪时下寒武统烃源岩已达过成熟早中期生干气阶段,上奥陶统和下志留统烃源岩进入了高成熟晚期至过成熟早期阶段,处于生气高峰期.这2套优质烃源岩的存在,可为湘鄂西、鄂西渝东和雪峰山推覆带等地区下组合的油气生成、成藏提供雄厚的物质基础.      

HYDROCARBON POTENTIAL IN JORDAN

The paper presents results from a range of petroleum exploration studies carried out in Jordan – some regional in approach, others focussed on the NE of the country – together with a review of existing literature and industry reports. The dominant active structural feature in Jordan is the NNW‐SSE striking Dead Sea Transform, characterised in southern Jordan by extensional splay fault arrays, pull‐apart basins and relay‐sag basins. Elsewhere in the country there are regional‐scale strike‐slip faults (ENE‐WSW, NNW‐SSE) with multiple phases of reactivation. Stratigraphic studies have identified potential reservoir intervals within the Lower Palaeozoic Salib, Umm Sahm, Disi and upper Dubaydib (Risha Sandstone Member) Formations, and also within the Triassic and Cretaceous intervals. Potential source rocks occur within the Lower Palaeozoic Burj, lower Hiswa and Dubaydib Formations and at basal and Upper Silurian levels, with limited additional potential in the Triassic and possibly Permian successions. Apatite fission track analysis (AFTA), zircon fission track analysis (ZFTA) and vitrinite reflectance (VR) studies of selected wells and outcrop samples indicate that the thermal history of eastern Jordan is dominated by the effects of two major periods of relatively deep burial, with subsequent exhumation phases beginning in the Late Palaeozoic and Late Cenozoic. An intermediate episode (Mesozoic) of deep burial and exhumation is possible. Significant variations in heat flow regimes and burial patterns occur in different parts of Jordan, probably controlled by deep structure and burial history. Over much of the north of the country, the Lower Palaeozoic succession is in the gas window and the underlying section is overmature. The main hydrocarbon generation and expulsion phase in this region was in the Late Palaeozoic and was terminated by “Hercynian” (Late Palaeozoic) uplift. Further south, the Silurian and Upper Ordovician sections are in the oil window, and deeper source intervals are mature for gas. The Triassic interval is a valid hydrocarbon play in the NW and NE of Jordan, with oil sourced from either Permian, Triassic or Cretaceous kitchens. Upper Cretaceous source rocks within the thicker Mesozoic sections in the Azraq Graben are in the oil window and have sourced the small‐scale Hamza oilfield. In addition to the known widespread Upper Cretaceous – Paleocene oil shale potential in Jordan, the Ordovician and Silurian sections have potential for shale gas in northern Jordan and for shale oil further south.     

塔里木盆地满加尔凹陷下古生界烃源岩的再认识

综合考虑下古生界烃源岩的纵向分布特征,认为塔里木盆地满加尔凹陷下古生界烃源岩主要发育中、下寒武统,中、下奥陶统和上奥陶统3套烃源岩.中、下奥陶统黑土凹组烃源岩与中、下寒武统烃源岩的沉积相特征和发育特征相似,有机质丰度高、类型好;上奥陶统烃源岩分布局限、类型差.3套烃源岩具有不同的热演化特征.以满加尔凹陷中西部地区为例,中、下寒武统烃源岩在加里东晚期-海西早期进入生油高峰阶段,中、下奥陶统烃源岩在海西晚期进入生油高峰阶段,上奥陶统烃源岩则在燕山晚期-喜马拉雅期进入生油高峰阶段.满加尔凹陷古生界烃源岩的三分法能更准确地反映下古生界烃源岩的实际分布情况,同时构筑了解决油气来源、油气成藏观点冲突的框架,能更准确认识不同地区海相原油的混源特征.