松辽盆地西部斜坡区萨尔图油层油气分布特征及控制因素

通过对松辽盆地西部斜坡区萨尔图油层已发现油藏的油气藏类型、分布特征及控制因素的系统分析,认为西部斜坡区的萨尔图油层从东到西含油气层位逐渐减少,主要发育砂岩上倾尖灭油藏、岩性—构造油藏、构造—岩性油气藏、微幅背斜油气藏及岩性油气藏等5种油气藏类型,其中以构造—岩性复合油气藏为主;西部斜坡的北西向的3条油气运移路径控制了西斜坡区油气的分布,北东向及北北东向的构造带控制着油气的聚集部位;鼻状构造样式、地层超覆构造样式及与砂体展布的匹配关系控制着油气富集程度和油气藏类型.     

蠡县斜坡鼻状构造成因及其对成藏的控制作用

蠡县斜坡的鼻状构造带控制了油气的运聚与成藏,此构造带主要由基底古凸起背景下的继承性发育和后期的差异压实作用形成,具有持续发育、幕式演化的特征,可分为沙四段、孔店组——基底、沙三段——沙一下亚段、沙一上亚段和东营组4个阶段.这种特征对油气成藏具有3个控制作用:鼻状构造的发育期次控制砂体在两翼形成超覆尖灭型砂体,后期鼻状构造脊部发育河道透镜状砂体;长期的构造高部位控制了油气的运聚,可形成断鼻油藏、上倾尖灭油藏、砂岩透镜体油藏和构造-岩性油藏;构造-岩性油藏是蠡县斜坡最普遍的油藏类型.     

塔里木盆地孔雀河地区构造变形特征及其控油气作用

根据塔里木盆地孔雀河地区地层层序及接触关系,将沉积盖层分为3大构造层,按古生界和中生界2大构造层重新划分构造单元;将区内断裂按走向划分为4组,以北东和北西向为主,断裂—褶皱组合样式有5种类型,以挤压构造为主。构造变形具有复合叠加特征,东西向表现为不对称的复式背斜;南北向以斜坡加断鼻构造为主;垂向上,下古生界以大型古鼻隆为特征,主要形成于加里东晚期—海西期;石炭系表现为缓凹缓坡;中生界总体表现为南西倾的大型斜坡,在此背景上发育断裂背斜圈闭,形成于燕山早期。长期构造演化控制了各类圈闭的形成;继承性的古隆起、古斜坡是油气运移的有利指向区;通源断裂是油气成藏的基本条件;保存条件对油气成藏至关重要。最后指出该区油气勘探的4大领域:西北部库南地区寒武—奥陶系碳酸盐岩潜山—内幕构造,西部草湖地区石炭系背斜和地层超覆圈闭,中南部普惠地区和东部龙口—维马—开屏地区侏罗系、志留系背斜构造。     

南阳凹陷东部复杂断裂带油气勘探目标分析

南阳凹陷东部地区构造活动强烈,断层十分发育,是比较典型的复杂断块含油气区,与断层有关的油气藏数量众多。含油气圈闭一般在鼻状构造背景条件下形成,往往被断层分割而复杂化,而断块(断鼻)则成为一个基本的含油气单元。通过对东部地区斜坡带复杂断块区的油气成藏规律的归纳和总结,寻找到了控制油气藏形成的关键因素,指出南阳凹陷魏岗、张店鼻状构造的继承性发育十分有利于油气聚集,是有利勘探方向,斜坡带发育的各种断块是有利的油气聚集带。     

巴彦浩特盆地构造样式分析及其意义

巴彦浩特盆地是在早古生代早期的秦、祁、贺三叉裂谷系交岔带发育起来的复合－叠加型盆地。由于其所处的特殊的构造位置和复杂的构造演化历史,使盆地发育了丰富多样的构造样式：压缩构造样式主要有叠瓦状冲断层、背冲、对冲构造组合、牵引背斜、滚板构造等;伸展构造样式主要有铲形正断层与掀斜断块、反向断层与滚动背斜、“垒－堑”构造等;走滑构造样式主要有花状构造、雁列断层等;另外,还有与重力等其它因素有关的构造样式发育,如压实构造、底辟构造等。不同的构造样式伴生有不同的油气圈闭类型,综合分析石油地质条件认为：黑汕托－通古楼背斜构造带为最有利构造带,阿门子－查汗背斜构造带次之,并预测该盆地具有良好的油气勘探前景。     

渤西地区断裂体系与油气运聚

研究了渤西地区的断裂体系 ,以及由断裂体系控制的局部构造带的分布和油气运聚规律。渤西地区的圈闭有沿断层和凸起区分布的特点。凸起或低凸起区构造带以潜山、披覆背斜、地层超覆圈闭为主 ,边界断层下降盘常发育滚动背斜、断鼻圈闭 ,低凸起区是形成大、中型油气藏的有利场所。凹陷内的大断层两侧发育断块、滚动背斜、断鼻构造及凹中隆 ,已发现的中、小型油气田呈串珠状分布于大断层两侧。本区断层的发育对油气运移与聚集起重要作用 ,两组断层的交汇处 ,钻探成功率很高。     

泌阳凹陷北部斜坡带油气富集条件及油藏类型

近年在泌阳凹陷北部斜坡带先后发现五个油田,形成一个面积较大的油气富集区。该区油气富集条件主要有:①继承性的沉积-构造复合斜坡是油气运移的主要指向;②多个砂体发育提供了良好的储集条件;③一系列鼻状构造对油气富集起着控制作用;④两组断层为油藏的形成提供了遮挡条件;⑤区域不整合面上的盖层使浅层油藏得以保存。该斜坡存在多种类型油藏,而以断鼻、断块、地层不整合油藏为主。     

准噶尔盆地坳陷湖盆坡折带在非构造圈闭勘探中的应用

准噶尔盆地西北缘地区,多级坡折带十分发育,对层序地层发育、地层超覆叠置、岩性纵向组合以及沉积体的纵横向展布具有重要的控制作用。多级坡折带对非构造圈闭的控制主要表现为:非构造圈闭紧邻多级坡折带发育,沿着坡折带呈串珠状展布;非构造圈闭在纵向上发育具有继承性的特点;非构造圈闭发育的类型随着坡折带所处的地理位置的不同而不同,靠近盆缘的坡折带以形成地层超覆和削截为主的非构造圈闭,向盆地方向,地层圈闭逐渐减少,以地层-岩性圈闭或岩性圈闭为主。多级坡折带的存在导致了在盆地的不同地理位置发生不同的沉积剥蚀响应,控制了构造圈闭的储、盖组合。另外,断裂坡折带中的断裂及挠曲坡折带处发育的裂缝,成为油气运移的通道,有利于油气运聚。由于坡折带的深部构造往往是早期的有利聚油构造,因此坡折带又是深部构造中聚集的油气再次垂向运移分配的有利聚集场所。     

渤西地区断裂体系与油气运聚

研究渤西地区的断裂体系,以及由断裂体系控制的局部构造带的分布和油气运聚规律,渤西地区的圈闭有沿断层和凸起区分布的特点,凸起或低凸起区构造带以潜山,披覆背斜,地层超覆圈闭为主,边界断层下降盘常发育滚动背斜,断鼻圈闭,低凸起区是形成大,中型油气藏的有利场所,凹陷内的大断层两侧发育断块,滚动背斜,断鼻构造及凹中陷,已发现的中、小型油气田呈串珠状分布于大断层两侧,本区断层的发育对油气运移与聚集起重要作用,两组断层的交汇处,钻探成功率很高。     

南堡凹陷的形成演化与油气的关系

南堡凹陷是一个中生代开始发育的含油气凹陷,经历了断陷期和坳陷期两个演化阶段,具幕式沉积特点。区内构造带呈环状展布,可分为周边凸起潜山构造带、近边或裙边构造带及凹陷中央构造带。以高柳断层为界,呈南北分区的格局。圈闭的形成与展布明显受构造演化控制,断陷期以背斜、潜山圈闭为主,坳陷期以各种类型的断块、断背斜圈闭居多。     

GEOLOGY OF THE NORTH FALKLAND BASIN

The North Falkland Basin comprises two main structural elements: a north-south trending graben, termed the North Falkland Graben; and a set of subsidiary basins to the west of this graben, also controlled by north-south trending extensional faults, but which have been constrained by NW-SE oriented, reactivated Palaeozoic thrust faults. The North Falkland Graben can be divided, in its northern part, into western and eastern depocentres, which are separated by a north-south trending intra-graben high.
Early syn-rift, late syn-rift, early post-rift and late post-rift successions have been identified within the North Falkland Graben. The subsidiary grabens to the west probably contain only early syn-rift deposits overlain by late post-rift sediments: these basins were possibly uplifted along the shoulder of the main graben during its mainphase of extension in the Late Jurassic to Early Cretaceous.
Although predictions of sediment-infill type have only been made by regional correlations and seismic facies analysis in these undrilled basins, two major deltaic units of early post-rift age are confidently inferred to be present in the North Falkland Graben, and to pass laterally into possible anaerobic mudstones of source-rock quality.
This petroleum system will soon be tested by a number of oil companies sharing production licences for the entire axial area of the North Falkland Graben.     

苏北盆地高邮凹陷北斜坡西部油气运移研究

通过甾烷、萜烷、轻烃、含氮化合物等地球化学参数对苏北盆地高邮凹陷北斜坡西部油气成熟度和油气运移进行了研究,得到3点认识:第一,码头庄地区为低-未成熟油,赤岸地区为成熟油,其中韦5和韦8块为生物降解油,两地区的油气分别来自不同油源区;第二,轻烃运移参数显示赤岸地区油气来自邵伯次洼,具自东向西的运移特征;第三,含氮化合物运移参数显示赤岸地区油气运移方向为自东向西,码头庄地区油气则自南向北运移.     

华北与扬子两板块的拼贴方式与扬子北缘古生代盆地应变特征

洋板块的消减及其后两侧陆块的拼合,是板块构造作用的两个不同阶段.分隔扬子与华北两板块的古秦岭洋,于晚志留世向北单边俯冲关闭.根据秦岭造山带内发育的大型推覆体构造组合及其配置关系,推覆体岩片内的变质相倒置、推覆岩片内应变标志物的显微构造特征和应变参数的测量及南秦岭大型泥盆纪—石炭纪前陆盆地的厘定,均一致确证了华北板块与扬子板块于420～380Ma至340～320Ma之间以仰冲兼右行剪切的方式碰撞拼贴.对扬子北缘古生代盆地应变标志物有限应变测量研究表明,扬子北缘古生代盆地从南向北可划分为4个应变量不同的应变区:无应变或弱应变区、强应变区、中等强度应变区和强应变区.应变区划分的构造学意义:a)扬子克拉通北缘是寻找古生代油气藏的有利地区;b)南秦岭造山带是晚加里东和海西-印支运动形成的复合山链.通过对扬子北缘古生代盆地构造变形特征,包括褶皱特征、逆冲-推覆构造特征、应变标志物的应变特征分析,估算南秦岭造山带的构造缩短量为918.8km.     

THE PROVENANCE AND DISTRIBUTION OF THE PALAEOCENE SANDS OF THE CENTRAL NORTH SEA

A study of the detrital heavy minerals from Palaeocene sandstones of the central North Sea basins has revealed that variations exist which cannot be explained in terms of varying conditions either during or after deposition, and therefore reflect the influence of distinct source areas. Four sand bodies have been defined on a mineralogical basis, two of which occur in the Central Graben and southern Viking Graben, derived from the E. Shetland Platform, the other two being developed in the Moray Firth area, derived from the Scottish landmass. These sand bodies, when related to the existing lithostratigraphic framework, define four phases of basin subsidence, with the sand depocentre alternating between the Central Graben and the Moray Firth basin. This oscillation in basin subsidence, the association with volcanogenic sediments and the apparent basement control on distribution of sands in the Moray Firth indicate a degree of tectonic control hitherto undescribed for the Palaeocene of the area.
Studies of sandstones in or around the inferred source areas have revealed that the metamorphic basement was the major contributor to the sands of the Moray Firth, rather than the pre-existing sandstones of Devonian, Permo-Trias or Jurassic ages which occur on the margins of the Firth. Likewise the Old Red Sandstone or Permo-Trias sandstones of the East Shetland Platform are not suitable source rocks for the sands of the Central Graben and in this case it has been necessary to postulate the existence, at least until the end of Palaeocene times, of Carboniferous sands on the Platform. Such sands in the central North Sea have been shown to possess a mineralogy not dissimilar from that of the Palaeocene sands in question.     

SECOND-ORDER SEQUENCE STRATIGRAPHY OF THE PALAEOZOIC OF NORTH AFRICA

A synthesis of the sedimentology and sequence stratigraphy of the Palaeozoic succession of North Africa is presented. Two chronostratigraphic correlation panels have been constructed at roughly right angles to each other across North Africa, in WNW-ESE and NNW-SSE orientations. The panels illustrate the way in which sedimentology and hydrocarbon geology vary across the continent through time. The Palaeozoic succession is divided into five second-order sequences (NA 1, Early Cambrian to Late Ordovician; NA 2, Late Ordovician to Late Silurian; NA 3, Devonian; NA 4, Carboniferous; NA 5, Permian), with sequence boundaries, maximum flooding surfaces and systems tracts being defined for NA 1 to NA 4. Palaeogeographic reconstructions for the North African region from the Cambrian to the Carboniferous are illustrated, and a sea-level curve based on the panels and palaeogeographic reconstructions is compared to other published sea-level curves. The proximity of the North African region to the South Pole during the Palaeozoic and its relative tectonic stability suggest that sea-level curves derived from the area should closely reflect Palaeozoic glacio-eustasy. This study may be used to investigate the occurrence of reservoir, seal and source rocks away from areas of data control, and is intended to provide a useful framework for future third-order studies.     

华北盆地南部构造样式分析

通过对南华北盆地典型地质剖面和地震剖面的研究,对盆地的构造样式进行分析和归类,厘定出5种主要构造样式,即逆冲推覆、伸展、走滑、反转和重力滑脱。在此基础上,由点及面地深入研究了该地区盆地性质和区域构造背景。探讨了华北盆地南部构造样式与油气聚集的关系,勘探实践表明油气大多集中在伸展构造样式的圈闭中,同时也要加强逆冲推覆和反转构造样式的圈闭研究。     

苏北溱潼凹陷北坡阜三段地震层序分析

在溱潼凹陷北坡阜三段主要目的层段进行地震层序精细描述的基础上,结合岩心、测井资料进行了综合分析,并以三维可视化资料对储层展布进行了验证。通过地震相类型的沉积微相解释,编制了地震相平面图和沉积微相平面展布图,从而预测了有利储层的空间展布。     

苏北拗陷区盐城凹陷地震地层学分析

本文用地震地层学的方法,对盐城凹陷地震剖面作了初步的分析.根据地震反射波的终止特征,将盐城凹陷新生界划分成11个地震亚层序,并根据各亚层序的区域意义,分别归属于3个层序或2个超层序。在地震层序划分的基础上,作者利用地震反射结构、振幅、连续性和层速度特征,着重对B_3和B_6亚层序进行了地震相分析。结合本区现有的钻井地质资料,进行综合转相工作,恢复了渐新统的沉积相和沉积环境,指出油气聚集的有利部位。文章认为:渐新世早期,盐城凹陷是向心充填式断陷湖泊沉积。多源水流自北向南,自西向东汇聚于南部深湖区。凹陷南陡北缓,从南向北呈湖泊——扇三角洲——三角洲平原相的沉积特征。南部陡坡带发育有洪积——冲积沉积。渐新世后期,向心式断陷盆地转为超越式以河流相沉积为主的沉积盆地。来自北、东北、西三个方向的水流,在凹陷中部汇聚后,沿盐城大断裂前缘向东流去。作者指出:小型的扇三角洲是B_8亚层序沉积类型油气勘探的最有利部位。主河流砂相沉积,结合构造的有利部位是B_6亚层序构造——沉积复合次生油气勘探的有利部位。     

塔里木盆地北部卫星象片解译初见成效

1979年解译出的168号环形影象异常,目前已被证实是一个高产油气田。卫星象片直接反映地貌特征,因而也大体上反映深部构造轮廓。