There are many methods of studying and mapping of lithofacies paleogeography. This paper will describe the methodology of lithofacies paleogeography that was advocated by the present author, "Single factor analysis and comprehensive mapping method", with the example from the lithofacies paleogeographic study and mapping of Majiagou Group of Middle Ordovician of Ordos Region. By " single factor" , meant is the factors which can independently reflect certain aspects of the sedimentary environments. Single Factor Analysis and Comprehensive Mapping Method includes three steps. First, earnest petrological and petrographical study of each section should be made in order to obtain various firsthand complete and reliable quantitative and qualitative data, especially quantitative data, and to understand the characteristics of sedimentary environments of each stratigraphical interval in the section. Second, select those factors which can independently reflect some aspects of sedimentary environments ( i. e, single factors) from these quantitative data. And then the percentage content of each single factor in each section of the whole area, followed the requisite mapping unit, should be calculated to draw out various corresponding fundamental single factor maps. They are mainly various isoline maps. These fundamental single factor maps can quantitatively reflect different characteristics of sedimentary environments of the slratigraphical interval of the area. This is Single Factor Analysis. Third, Having synthesized these fundamental single facotr maps and combined with other quantitative and qualitative data and other regional geology data, through all-sided analysis and comprehensive judgement, with the dross discarded and the essential selected, the false eliminated and the true retained, the lithofacies paleogeographical maps of the mapping unit of the area can be compiled finally. This is Comprehensive Mapping. The core of this method is quantification. That is, on the basis of quantitative data, starting with analysis of quantitative fundamental single factor maps, then through comprehensive analysis and judgement, finally the quantitative lithofacies paleogeographical maps can be compiled. In these lithofacies pqleogeographicai maps, the determination of each plaeogeographical unit is based on definite quantitavtive data. This type of lithofacies paleogeographical maps is therefore no loger sketchy. This makes lithofacies pqleogeographicai maps developed into a quantitative stage. The following single factors are used in this paper: thickness, terrigenous materials, shallow-water grains, penecontemporaneous dolostones, gypsum, colors and so on. On the basis of various fundamental single factor maps of each formation of Majiagou Group of Ordos Region, combined with other quantitative and qualitative data, through all- sided analysis and judgement, the lithofacies paleogeographical maps of Majiagou Age I to VI of Middle Ordovician of Ordos Region wrer drawn out. The lithofacies paleogeography of Majiagou Age I may be generalized by following: Outside the lands wre flats (dolomite flats, etc); Inside the flats were lakes (gypsum salty lakes and gypsum lakes); Outside the flats were banks (embryonkc banks); Outside the banks were seas (open seas) and outside the seas were troughs (deep-water troughs). In Majiagou Age Ⅱ, the transgression was enlarged so that the whole area was open sea except three small lands. In the open sea there were some embryonic banks and penebanks scatterred. The lithofacies plaeogeography of Majiagou Age Ⅲ and Ⅴ were similar to that of Majiagou Age I. The lithofacies paleogeography of Majiagou Age n and IV were similar to that of Majiagou AgeⅡ. Generally speaking, form Majiagou Age Ⅰ to Ⅵ, three transgressions and three regressions appearred alternatively. They constructed a series of complete cycle of transgression and regression of triple assemblage and three similar, opposite and complementary, antithetical assemblages of lithofacies paleogeography in Majiagou Age of Middle Ordovic

古地理学及岩相古地理学的研究及编图方法较多,本文以鄂尔多斯地区天然气的主要产层中奥陶统马家沟群的岩相古地理研究及编图为例,阐述笔者倡导的岩相古地理学的方法论,即单因素分析综合作图法

The author initiated and adopted the single factor analysis and multifactor comprehensive mapping method as a new methodology of quantitative lithofacies palaeogeography in order to reconstruct quantitative lithofacies palaeogeography By meaning， single factors are the factors which can independently reflect some characteristics of sedimentary environments of a stratigraphic interval of a section in an area Presence or absence as well as high or low percentage of single factors can all independently and quantitatively reflect some characteristics of sedimentary environments of the interval of the section in the area, such as water depth, water energy, nature of the sedimentary environments, etc The thickness of the interval and its specific rock types, texture constituents, mineral composition, chemical composition, fossils and their ecological assemblages, etc, can all be taken as single factorsThe single factor analysis and multifactor comprehensive mapping method include three steps First, an indepth petrological and lithofacies study of each section, especially fundamental section, should be made in order to obtain various reliable firsthand qualitative and quantitative data, especially quantitative data, and to understand the characteristics of sedimentary environments of each interval of each section Second, according to the mapping units, from the quantitative data of each section, select those factors which can independently reflect the characteristics of sedimentary environments, ie the single factors Then the statistics of the percent contents of various single factors of each mapping unit of each section in the area are made Based on these percentage data, the various quantitative single factor maps, mainly isoline maps， are composed These single factor maps can quantitatively reflect the characteristics of sedimentary environments of the mapping unit of the area from different aspects This is the single factor analysis Third, through superimposition and synthesis of these quantitative single factor maps, combined with other quantitative and qualitative data of this mapping unit of the area, with the dross discarded and the essential selected, with the false eliminated and the true retained, the quantitative lithofacies palaeogeography map of the mapping unit of the area can be composed This is the multifactor comprehensive mappingThe core of this methodology is quantification That is, based on the quantitative single factor data of each section, starting from analysis of various quantitative single factor maps, through superimposition and comprehensive analysis and judgement, finally the quantitative lithofacies palaeogeography map can be composed In such palaeogeography map, the definition of each palaeogeographic unit is based on quantitative data and quantitative single factor maps Therefore, such lithofacies palaeogeography maps are no longer sketchy and qualitative, but quantitative instead Quantification is the most important character of the author's lithofacies palaeogeography maps This makes lithofacies palaeogeography map and lithofacies palaeogeogaphy develop into the quantitative stage This is an important development in palaeogeography

笔者倡导并持续采用单因素分析多因素综合作图法这一定量的岩相古地理学方法论。单因素是能独立地反映某地区、某地质时期、某沉积层段沉积环境某些特征的因素,它的有无或含量的多少均可独立地反映该地区、该层段沉积环境的某些特征,如沉积环境水体的深浅、能量大小、性质等。某沉积层段的厚度、岩石类型、结构组分、矿物成分、化学成分、化石及其生态组合等，均可作为单因素。单因素分析多因素综合作图可分三个步骤：第一，是对各剖面尤其是各基干剖面进行认真的地层学和定量岩石学研究，取得各种第一手的定性和定量资料，尤其是定量资料，了解各剖面各沉积层段的沉积环境特征。第二，在已取得的各剖面的定量资料中，按要求的作图单位，选择出那些能独立地反映其沉积环境特征的因素，即单因素；并把全区各剖面各作图单位的各种单因素的百分含量都统计出来，作出各种相应的单因素图，主要是等值线图。这些单因素图可以从不同的侧面定量地反映该地区该沉积层段的沉积环境。这就是单因素分析。第三，把这些定量的单因素图叠加起来，并结合该地区该沉积层段的其他定量和定性资料，去粗取精，去伪存真，全面分析，综合判断，即可编制出该地区该沉积层段的定量岩相古地理图。这就是多因素综合作图。这一方法论的核心是定量，即以各剖面的定量单因素资料为基础，从各单因素图的分析入手，再通过各单因素图的叠加和综合分析判断，最后作出定量的岩相古地理图。在这种岩相古地理图中，各古地理单元的确定都有确切的定量资料和单因素图为依据。定量是笔者等用单因素分析多因素综合作图法编制出的岩相古地理图的最大特色。这就使岩相古地理图和岩相古地理学发展到了定量的阶段。这在古地理学中是个重大的进展。

Delta and lacustrine sedimentary facies are recognized from the Chang 9 interval of the Upper Triassic Yanchang Formation in the Ordos Basin.The deltaic plain distributaries channel sandbodies and deltaic front subaqueous distributaries channel sandbodies are high quality reservoirs.Based on the research of sedimentary facies，according to the single factor analysis and multifactor comprehensive mapping method，the sedimentary facies distribution of the upper and lower parts of Chang 9 interval of Yanchang Formation in the Ordos Basin were studied and mapped.The single factors include strata thickness，content of deep water sedimentary rocks，sandstone thickness，sandstone strata thickness ratio，authigenic chlorite development characteristics，paleontology characteristics，sedimentary structure combination characteristics.Discussion was made about the sedimentary evolution rule of the Chang 9 interval.The results show that the Chang 9 interval of Yanchang Formation was characterized by the deposition of multiple delta sedimentary system which surround the lake and have multiple water systems and multiple provenances.The meandering fluvial deltas were mainly developed in the northeastern Ordos Basin，and the braided fluvial deltas were mainly developed in the western Ordos Basin.The deltaic plain distributaries channel microfacies and deltaic front subaqueous distributaries channel microfacies were well developed.During the depositional period of the lower part of Chang 9 of Yanchang Formation，semi-deep custrine was only developed in the center of the Ordos Basin.During the depositional period of the upper part of Chang 9 interval of Yanchang Formation，the custrine basin began to expanded，lake shoreline moved to the land，lake area enlarged，and the semi-deep custrine deposition greatly developed.From the lower part to the upper part of Chang 9 interval of Yanchang Formation，the water depth changed from shallow to deep.Correspondingly，a set of oil shale with hydrocarbon generating potential are deposited in the study area.

鄂尔多斯盆地延长组长9油层组发育三角洲—湖泊沉积相，三角洲平原分流河道砂体和三角洲前缘水下分流河道砂体是最有利的储集砂体。在沉积相研究的基础上，根据单因素分析多因素综合作图法，选取了地层厚度、较深水沉积岩含量、砂岩厚度、砂地比、自生绿泥石分布、古生物化石分布和沉积构造分布等单因素，对鄂尔多斯盆地延长组长9油层组上下2段的沉积相平面展布特征进行了深入研究，并探讨了其演化规律。研究表明，鄂尔多斯盆地以发育多水系、多物源注入的环湖分布的多个三角洲为特色，东北部地区主要发育曲流河三角洲，西部发育辫状河三角洲，其中以三角洲平原分流河道和三角洲前缘水下分流河道微相较为发育。长9 2 沉积期，半深湖沉积在盆地内较为局限，长9 1 沉积期湖盆初始扩张达到最大范围，湖岸线向陆推移，湖域面积扩大，半深湖沉积较发育。由长9 2 沉积期到长9 1 沉积期，鄂尔多斯盆地沉积水体经历了由浅变深的过程，由此在长9 2 的顶部沉积了一套具有生烃潜力的油页岩。

Rock mechanic characteristics of the Tertiary gypsum cover in the north of Kuche depression is analyzed based on simulation experiment.Plaster rock,salt rock and mudstone are plastic material and have the ability of plastic deformation.Creeping shows that the Tertiary gypsum cover has strong fluidity.Plastic flow appears if the gypsum cover suffers tectonic stress.Under the influence of fault,the gypsum cover usually forms huge gypsum-mud cover tectonic trap,which is compact with high expulsion and pore fluid pressure so as to be good cover.Most of fractures and detachment fractures are formed by gypsum-mud rock creeping.And there are huge fracture groups filled with ooze in fracture zone,which have excellent enclosing function and hold gas back effectively.

根据模拟实验结果分析了塔里木盆地库车坳陷北部第三系膏盐质盖层岩石力学特征。膏岩、盐岩和泥岩为塑性材料,变形过程为典型的塑性形变,蠕变表明第三系膏盐质盖层具有较强的流动性。构造挤压使膏盐质盖层塑性流动,受断裂改造作用往往在构造圈闭上方形成巨厚的膏泥岩层。膏泥岩岩性致密,排替压力高,普遍具有异常高的孔隙流体压力,是一套优质盖层。盖层段内的穿盐断裂和盐内滑脱断裂多为膏泥岩蠕变形成的塑性断层,断裂带内部结构主要为软泥充填的大裂缝组合,伴生裂缝不发育,断裂静止期封闭性好,有效阻止天然气散失。

The depositionai features of Cretaceous braided deita in Kuga depression can be conciuded as that（1）the sediments are very coarse, and the median-grained sandstone and fine-grained sandstone are the main rock types with a proportion from 60% to 80% of the totai sandstones. The maximum can be up to 95%;（2）most of these sandstones are composed of feidspathic, iithic feidspathic and iithic sandstone with 30% ~ 50% of guartz and rich in iithociast;（3）sedimentary structures are mainiy massive bedding, iarge trough cross bedding and obiigue bedding with few paraiiei bedding, wave bedding and horizotai bedding;（4）main sedimentary period of the braided channei is fiood stage, so the sedimentation is characterized by rapid migration of channeis with different stages to form thick and continuous sandstone iayers by iots of super imposed sandbodies, which are separated by some thin intercaiated peiitic beds. Based on the data obtained from thin sections, cathodoiuminescence and SEM of outcrop and core sampies, the diagenes can be determined as compaction, cementation, dissoiution, repiacement, pressure dissoiution and recrystaiiization.According to authigenic minerai, ciay minerai, 5% in mix-iayered I /S, inciusion temperature and diagenetic types, the diagenetic stage of the Cretaceous in the study area have reached a period of the iate diagenetic stage. Features of ciay minerais show speciai types and assembiages formed under aikiine diagenetic environment. There are abundant pore types in Cretaceous sandstones, which inciude intergranuiar pore, intragranuiar pore, grain-dissoived pore, matrix-dissoived pore, intercrystai pore, primary intergranuiar pore and structurai fractures.

通过对库车坳陷白垩系辫状三角洲的研究,总结辫状三角洲的沉积特征是:1.由于辫状河流直入湖泊,沉积物比较粗,中砂岩和细砂岩占有相当的比例,可达 6 0 %～ 80 %,最高达 95 %。 2.成分和结构成熟度低—中等,一般为长石砂岩、岩屑长石砂岩和岩屑砂岩,石英含量 30 %～ 5 0 %,岩屑含量可高达 5 0 %以上,一般为 30 %左右,岩屑成分复杂。3.沉积构造以块状层理、大型槽状交错层理和斜层理为主,见平行层理、波状层理和极少量的水平层理。4.辫状河道的主要沉积期是洪水期,因而河道具快速迁移性,沉积作用具有阶段性,砂体之间多次重复叠加,在滨岸地区辫状砂体性质相似而垂向侧向连接,成为分布面积很大的砂体,砂层之间只有薄层的泥质夹层。对研究区露头和岩心的普通薄片、铸体薄片、阴极发光及扫描电镜等资料的分析研究,认为该区成岩作用包括压实、胶结、溶蚀、交代、压溶和重结晶等作用,并且以前三类为主。根据对自生矿物、粘土矿物、I/S间层中的S %、包裹体测温、成岩作用类型及特点等分析,判断研究区白垩系成岩阶段已达晚成岩A期。白垩系砂岩储层特殊的沉积—成岩水介质条件、构造—埋藏演化史、异常高压背景等决定了其特有的成岩序列演化的特点。白垩系巴什基奇克组上部和底部、巴西盖组砂

Cretaceous Bashijiqike formation in Kelasu structure zone, Kuqa depression, was selected as study layer. Salinity of syndepositional water body was acquired based on mensuration of content of “B” in mudstone interbedded sandstone. Salinity of interstitial fluid during burial diagenesis stage was identified on the basis of detailed micro-thermometry analysis of fluid inclusions in carbonate cement. It was noteworthy that the lateral and vertical distribution rules of salinity of interstitial fluid during burial diagenesis stage were similar to that of salinity of syndepositional water body, because of stabilization of structure setting and absence of sedimentary and structure leading system. So the fluid-rock system were not changed by exogenous fluid obviously. It was concluded that fluid-rock system had been relative sealing feature from syndepositional stage to burial diagenesis stage. And tectonic active hadn't disturbed the differentiation of carbonate cementation later. The characteristic of spatio-temporal differentiation of salinity of syndepositional water, controlled the extent of carbonate cementation during burial diagenesis stage.

以库车坳陷克拉苏构造带白垩系巴什基奇克组为研究层段,分别通过层间泥岩硼元素含量和碳酸盐胶结物流体包体显微测温,对不同成岩期地层流体盐度进行示踪对比。由于自沉积初始至埋藏成岩期碳酸盐胶结阶段,研究层段经历一段较为稳定的构造时期,再加上沉积及构造疏导体系的缺失,地层流体始终缺乏大规模交换与改造,不同成岩场之间水-岩体系在这一阶段呈现出一定的封闭性特征,使得研究层段在碳酸盐胶结期孔隙流体盐度时空分异较好地延续了同沉积期水体盐度的分异规律,这种延续性不仅体现在平面上,也体现在垂向上。研究层段在碳酸盐胶结期后经历了强烈的构造活动,但由于断层的封堵并未对流体介质进行有效的疏导,先期形成的碳酸盐胶结分异规律因而未受到明显干扰,从而呈现出同沉积地层水体盐度时空分异特征造就了埋藏成岩期碳酸盐胶结作用的时空分异规律。

Based on the plentiful data of drilling wells and outcrops， the sedimentary characteristics and palaeogeography of the Early Cretaceous have been analyzed. Continental alluvial(or pluvial)fan facies， fan delta facies， braided fluvial delta facies and lacustrine facies were developed in the Lower Cretaceous. They were widely distributed throughout  the Lower Cretaceous. Sedimentary systems are dominated by three types: alluvial fan-fan delta， braided fluvial delta， and shallow lacustrine.In the Tarim Basin,  Early Cretaceous deposition occurred in two areas: northeastern and southwestern part. The basin was an  inland separated depressional basin with arid and oxygenative climate conditions. During the deposition of the Kapushaliang Group in the early Early Cretaceous， shallow lacustrine basin with multi-provenances develop in the northeastern area of the Tarim Basin. The sediments were controlled by four provenances surrounding the basin. The topography of the basin was higher in the south， and lower in the north, and higher in the east, lower in the  west. There were mainly alluvial fan， fan-delta， and braided fluvial delta in the basin margin， and lacustrine facies in the hinterland of the basin. During the deposition of the Bashijiqike Formation in the late Early Cretaceous， a new tectonic activity period occurred in the margins of the Tarim Basin. The palaeoclimate was more torrid and arid. The lacustrine basin disappeared. Controlled by the four provenances， the extensive coarse grain alluvial fan and braided fluvial delta systems were mainly developed in the northeastern  Tarim Basin. The topography of the southwestern  Tarim Basin was higher in the west and lower in the east during the deposition of the Kezilesu Group. Controlled by the two provenances in the north of Kashi Mountain and palaeo-Kunlun Mountain， the sediments were distributed in the front of palaeo-Kunlun Mountain in a long and narrow belt. Mainly alluvial fan—fan-delta—shore-shallow lacustrine facies were developed， with thickness decreasing from west to east.

根据大量的钻井和露头资料，对塔里木盆地早白垩世沉积相特征和古地理进行了研究。塔里木盆地下白垩统主要发育冲积扇—扇三角洲、辫状河三角洲、氧化宽浅湖泊等3种沉积体系，包括陆相冲（洪）积扇、扇三角洲、辫状河三角洲、滨浅湖等沉积相，分布于下白垩统不同层位。塔里木盆地早白垩世主要包括塔东北和塔西南两大沉积区，总体为干旱氧化的内陆拗陷分割盆地。在塔东北沉积大区，早白垩世早期卡普沙良群沉积物受周缘4大物源区控制，为多物源的氧化宽浅湖盆环境，古地势呈“南高北低、东高西低”，盆地边缘以冲（洪）积扇、扇三角洲、辫状河三角洲相为主，盆地内部为滨浅湖亚相。早白垩世晚期巴什基奇克组沉积时期，塔里木盆地周缘进入一个新的构造活动期，古气候更加炎热干旱，氧化宽浅湖盆消失。在塔东北沉积大区，盆地受周缘4个主要物源区影响，以广泛分布的冲积扇—辫状河三角洲沉积体系占主体，盆地内部普遍为辫状河三角洲前缘—滨浅湖亚相沉积。在塔西南沉积大区，早白垩世克孜勒苏群沉积时期古地势呈“东高西低”，受北部喀什北山前和西南部古昆仑山2个物源区的控制，沉积物沿古昆仑山前呈狭长的条带状分布，沉积厚度自西向东减薄，主要是一套冲积扇—扇三角洲相和滨浅湖亚相沉积。

Being the biggest gas filed of the continental exploration in our country, Kela 2 gas field settle a foundation that Tarim basin is being to the important base of gas energy of "west gas to east" in our country.The main reservoir of Kela 2 gas field is the sandstones of Cretaceous Bashijiqike formation and the lower of Paleogene Kumugeliemu group, and the dolostones of the lower of Paleogene Kumugeliemu group.Thickness of the sandstone reservoir is 220.3-285.2m. Its porosity changes from 1.1% to 22.4%，the average is 12.83%. Its permerbility changes from 0.004×10-3μm2 to 1770.1×10-3μm2, the average is 51.46×10-3μm2. Primary intergranular pors are the main reservoir space. By comparing the sedimentary facies of the cored well and field section, the third member of Bashijiqike formation in Kela 2 gas field is fan delta front depositional facies. The main microfacies include the distributary channel ,gravitite and coastal-shallow lake.The types of rocks are sandy conglomerates, conglomeratic sandstones and brown mudstones.The second member of Bashijiqike formation in Kela 2 gas field is braided delta front depositional facies.The main microfacies include braided channel, distributary mouth bar and interdistributary bay. The types of rocks are brown medium to fine litharenite interbeded thinner mudstones. The first member of Bashijiqike formation in Kela 2 gas field is braided delta plain depositional facies. The main microfacies include braided channel and interdistributary bay. The types of rocks are brown medium to fine litharenite. During Bashijiqike stage,with paleo-climate arrid and torrid, there developed many fan-shaped depositional systems along the north frontier. They are constituted of many braided channel delta plain, and not a only one braided channel delta plain. In Kela 2 gas field, Bashijiqike formation reservoir geometry occures a lot of braided channel arising one erosion after another. Microfacies of every member has steady extensive distribution. Sandbodys connect continuously each other, and muddy partition beds are thinner and not continuous. Being a suit of excellent gas reservoir, Bashijiqike formation reservoir are charactristics of great thickness, extensive distribution, more continuous, high porosity and permeability and a few barrier beds in the space.

克拉2气田是我国陆上勘探发现的最大气田，它的发现奠定了塔里木盆地做为我国 “西气东输” 重要天然气基地的资源基础。克拉2气田产层主要为下白垩统巴什基奇克组砂岩、下第三系库姆格列木群底砂岩和白云岩，其中下白垩统巴什基奇克组砂岩储层厚度为220.3-285.2m，孔隙度为1.1-22.4%，平均12.83%；渗透率为0.004-1770.1×10-3μm2,平均51.46×10-3μm2。砂岩储层以剩余原生粒间孔为主。通过钻井和露头剖面沉积相对比，克拉2气田巴什基奇克组第三段为扇三角洲前缘沉积，主要微相有水下分流河道、水下重力流和浅湖泥等，岩性以砂砾岩、含砾砂岩和褐色泥岩为主；第二段为辫状河三角洲前缘沉积，主要有水下辫状河道、河口砂坝和分流间湾等微相，以棕褐色中细砂岩夹薄层泥岩为主；第一段为辫状河三角洲平原沉积，主要有远端辫状河道和分流间湾微相，以棕褐色中细砂岩为主。巴什基奇克组沉积时期，古气候以干旱炎热为主，北部发育多个扇体，在平面上相互连接、叠置形成多个物源出口，形成了一系列由辫状河道组成的辫状河三角洲，而非单一辫状河流形成的沉积体，从而形成大面积分布的稳定砂体。沉积微相对比表明，巴什基奇克组储层是由互相切割的多个辫状河道砂体叠置而成，各段微相在横向上分布十分稳定，各砂体互相连通、连续性好，泥岩夹层薄、不连续，空间上具有厚度大、分布广、连续性好、物性好和隔夹层少的特点，为一套优质天然气储层。

       According to massive drilling data, core samples, thin slice analysis, well logging and production tests, this paper studies the characteristics and control factors of the Lower Cretaceous Bashijiqike Formation sandstone in the Dabei region, Kuche sag, Tarim basin. The rock type is dominantly the feldspar lithic sandstone and the rock debris arkosic sandstone in the Dabei region, to a lesser extent, the rock debris silicarenite and the lithic sandstone. The reservoir spaces include primary intergranular pores, intergranular dissolution pores, few feldspar and lithic dissolution pores, corrosion splits, build joints and micropores, and it is low porosity to extra-low permeability reservoir. The unusual growth of cracks provides the base for the high production of deep-burial low porosity to extra\|low permeability reservoirs. The conditions of the deep\|burial reservoirs are improve obviously after the later period diagenesis and tectonism. The controlling factors of the reservoir development include sedimentary micro-facies, diagenesis, tectonism, rock salt layer, abnormally high pressure and the burial depth, and structure extrusion and corrosion are the key control factors.

        根据大量的钻井资料及岩心、薄片分析并结合测井和生产测试资料，探讨了塔里木盆地库车坳陷大北地区白垩系巴什基奇克组储层特征及其控制因素。研究认为，库车坳陷大北地区白垩系巴什基奇克组砂岩以长石岩屑砂岩、岩屑长石砂岩为主,次为岩屑石英砂岩和岩屑砂岩；储层发育原生粒间孔、粒间溶孔、少量长石、岩屑粒内溶孔、溶蚀逢、构造缝和微孔隙等储集空间，属特低孔特低渗储集层，裂缝的异常发育为这种特低孔特低渗深部储层的高产提供了基础，在成岩阶段后期的改造作用及构造作用下，其储集条件明显变好，影响该区储层发育的控制因素有沉积微相、成岩作用、构造作用、膏岩层、异常高压和埋藏深度等，其中构造挤压和溶蚀作用是其主控因素。

The Cretaceous in the Kuqa Depression was an arid intracontinental depression，in which only the Lower Cretaceous marked by a set of arid redbed was developed and could be divided into the Yageliemu Formation，the Shushanhe Formation，the Baxigai Formation and the Bashijiqike FormationSeveral types of sediments constitute this set of arid redbediepluvialfan conglomerates，intermittent river sandy conglomerates，aeolian sandstones and desertlake  purple mudstones These sediments of the Cretaceous in the Kuqa Depression made up a typical desert sedimentary systemThe cyclicity in stratigraphic records are reflected by the alternation between the coarse clastic pluvial sediments in the lower part and the fine desertlake sediments in the upper partAeolian sandstones were formed in the initial stage and the regressive stage of the lakeforming periodAccording to the cyclicities in the stratigraphic records represented by the sedimentary facies succession，iethe succession constituted by pluvial coarse clastic sedi ments in the lower part and fine desertlake sediments in the upper part,the Lower Cretaceous in the Kuqa Depression could be divided into five thirdorder sedime ntary sequences，ieSQ1to SQ5Because the top and bottom boundaries of the Lower Cretaceous in the Kuqa Depression are obvious tectonic unconformities，the Lower Cretaceous in the Kuqa Depression makes up a secondorder tectonic sequenceThere is regularly ver tical sacking pattern for thirdorder sedimentary sequences in the secondorder tect onic sequence This feature is reflected by that more coarse pluvial clastic sedi ments were developed in SQ1 and SQ5，and the middle part of the Lower Cretace ous in the Kuqa Depression made up by SQ2 to SQ4 was always developed with more fine d esertlake sedimentsDifferent from marine strata，the cyclicities represented  by sequence sin stratigraphic records in the Lower Cretaceous of the Kuqa Depression are mai nly caused by the episodic tectonic subsidenceDue to a high difference of toporgr aphy，more coarse clastic pluvial sediments were  formed in the initial stage of sedimentary basin subsidence，corresponding to the isostaticsubsidence stage during which the lake was formed and more fine de sertlake sediments were developedOn the basis of sequence stratigraphy，the pala eogeographical visage as well as the evolution process of sedimentary facies and palaeogeography for the Cretaceous of the Kuqa Depression are clearly reflected by a series of the panel diagram of sequence stratigraphic frameworks and their corresponding outline maps of sedimentary facies and palaeogeography

白垩纪的库车坳陷是一个干旱气候条件下的内陆坳陷，其中只发育下白垩统，为一套干旱红层地层，进一步划分为亚格列木组、舒善河组、巴西盖组和巴什基奇克组。该套干旱红层，包括洪积扇砾岩、间歇性河流砂砾岩、风成砂岩和沙漠湖紫红色泥岩等沉积。这些沉积在地层记录中常以一种特别的旋回性形式产出，在不整合面及其相关面之上首先沉积的是洪积扇砾岩和间歇性河流砂砾岩所构成的冲积沉积物，向上逐渐演变为沙漠湖红色泥岩，在成湖初期或湖退期发育了滨湖相风成砂岩，它们构成了一个较为典型的沙漠沉积体系。从冲积沉积到湖泊沉积构成总体向上变细的沉积相序组合。按照地层记录的旋回性进行三级沉积层序划分，将库车坳陷下白垩统划分为5个三级沉积层序即SQ1至SQ5。下白垩统的顶和底界面均为间断时间很长的区域不整合面，由它们所限定的下白垩统本身则构成一个二级构造层序，在二级构造层序内三级沉积层序常常形成有规律的叠加形式，下部的SQ1和上部的SQ5发育较多的冲积粗碎屑物，中部SQ2至SQ4则以湖泊相沉积为主。与海相地层不同，库车坳陷白垩系中由三级层序和二级层序所代表的地层记录中的中周期和长周期旋回的主要控制因素是幕式构造沉降，沉降初期由于地形高差大而以发育冲积粗碎屑物为主，均衡沉降期则与成湖期相对应从而发育较多的细粒沙漠湖沉积。以沉积物的时间演化序列和沉积相的空间展布形式所代表的规律性入手，建立库车坳陷下白垩统的层序地层格架，在层序地层框架内，系列层序地层格架栅状图和相应的古地理图较为清晰地反映出早白垩世库车坳陷的古地理面貌，以及相应的沉积岩相古地理演变过程。

Different viewpoints have been proposed about the delta sedimentary facies developed in the Member 1 of Qingshuihe Formation of Lower Cretaceous in Shinan 31 wellblock in central Junggar Basin. The authors considered it was the product of tractive current with strong hydrodynamic conditions according to the stratification character, the composition texture, the texture maturity, the developing characteristic of the pore of the conglomerates and the texture, structure, granularity and distribution characteristics of the sandstones. Its sedimentary environment belonged to the braided fluvial delta. Through the detailed observation and description of cores, combining with the logging facies analyses, on the basis of single well facies analyses of the 211 wells in the Shinan 31 wellblock, according to the across-well analyses and the synthetic analyses of sedimentary facies, it is concluded that all kinds of subfacies of the braided fluvial delta facies were developed in the study area. The sedimentary microfacies including the braided channel, fluvial flood deposit, subaquaeous distributary channel, mouth bar, front delta mud etc .， were identified. During the earlier sedimentary period of the Member 1 of Qingshuihe Formation(K 1 q 2 1 ), the study area was dominated by lacustrine facies and braided fluvial delta was only developed in the southeast of the study area. Then the two deltas in two directions developed towards the same direction(K 1 q 1-3-4 1 ,K 1 q 1-3-3 1 ). Then, the delta plain disappeared in the southeast and only delta front was developed(K 1 q 1-3-2 1 ). During the sedimentary period of K 1 q 1-3-1 1 , it was dominated by fine-grained sediments and the sedimentary setting was similar as the former period. During the sedimentary period of K 1 q 1-2 1 , the braided fluvial delta plain and delta front were developed in the north, while in the southeast, only delta front was developed. In the late period of the Member 1 of Qingshuihe Formation(K 1 q 1-1 1 ), due to the sudden rise of the lake level, the study area was dominated by front delta facies and was composed of front delta muds with the development of strip-belt-shaped front delta ditch sandstones.

针对准噶尔盆地腹部石南31井区下白垩统清水河组一段三角洲相沉积的不同认识,根据砾岩的成层性、组构、结构成熟度、孔隙发育等特征,以及砂岩的结构、构造、粒度特征、砂体的空间展布特征,笔者认为清水河组一段是较强水动力条件下牵引流沉积的产物,其沉积环境属辫状河三角洲。通过对岩心的详细观察与描述,结合测井相分析,以石南31井区211口井的单井相分析为基础,依据连井相剖面分析和平面沉积相综合研究,认为该区辫状河三角洲的各亚相发育齐全,并识别出了辫状河道、河漫、水下分流河道、支流间湾、河口砂坝、远砂坝、前三角洲泥、前三角洲沟道砂等微相。在清一段早期（K 1 q 2 1 ）,研究区以湖泊相沉积为主,仅东南部为辫状河三角洲沉积。其后,研究区南北两个方向的辫状河三角洲相向推进（K 1 q 1-3-4 1 、K 1 q 1-3-3 1 ）；继而,东南部的辫状河三角洲平原消失,研究区内仅见三角洲前缘（K 1 q 1-3-2 1 ）沉积；K 1 q 1-3-1 1 沉积时期以细粒沉积为主,而沉积相格局则大致同前。同样，K 1 q 1-2 1 沉积时期,北方发育辫状河三角洲平原及前缘,东南方仅发育三角洲前缘。清一段晚期（K 1 q 1-1 1 ），由于湖平面快速上升,全区均演化为前辫状河三角洲亚相,主要由前三角洲泥构成,并且发育条带状分布的沟道砂沉积。

The Kuche petroleum system is a forland type one riched in oil and particularly natural gas generated from the Triassic and Jurassic source rocks including coal source. Many natural gas and condensate fields as well as some oil fields have been discovered, of which the natural gas and condensate are thought to have been generated mainly from coal source of Jurassic and the normal oil from the Triassic mudstone source. Study of these fields' accumulation timing and filling history is significant to exploration in Kuche and therefore the major concern of this paper. Based on synthetic analyses of trap timing, reservoir geochemistry (gas maturity correlation), hydrocarbon fluid inclusions, dew-point pressure and oil/gas-water contact evolution, 3 periods of the formation and filling history of oil and natural gas reservoirs in the Kuche petroleum system are discerned, i.e. early-middle Kangcun period (17～10 Ma), late Kangcun to early-middle Kuche period (10～3 Ma) and late Kuche to Xiyu period (3～1 Ma). The late Kuche to Xiyu period is the major one for formation of natural gas fields of high maturity to over-maturity in Kuche forland thrust belts, in which the discovered gas fields of Kela 2, Kela 3, Dabei 1, Yinan 2 and Tuzi 1 were formed. The late Kangcun to early-middle Kuche period is a critical moment for accumulation of oil and condensate of low to intermediate maturity. And the early-middle Kuche period is a minor one for formation of low-maturity oil and gas reservoirs sourced from coal-type organic matter. Oil and gas fields of early-middle Kangcun and late Kangcun to early-middle Kuche periods were distributed mainly in the Luntai uplift, whereas gas fields of late Kuche to Xiyu period totally in the Kuche forland thrust belts. The early formed oil and condensate accumulations in the forland thrust belts, if there is, have possibly been adjusted and even destroyed by the later strong orogeny and/or the intrusion of natural gas of high maturity and over maturity. The remanined oil accumulations in the thrust belts were mostly secondary reformed during the late Kuche to Xiyu period.

根据圈闭形成时间法、生烃史法、油藏地球化学方法、包裹体测温法、露点压力法、油气水界面追溯法等多种方法对库车油气系统油气成藏期综合分析认为，该油气系统具有多期成藏、多阶连续的成藏特点。其主要成藏期有3期:即晚第三纪康村早中期（17 #10 Ma）、康村晚期—库车早中期（10 #3 Ma）、库车晚期—第四纪西域期（3 #1 Ma）。前2 期为轮台凸起油气藏形成的主要时期，形成三叠系湖相油藏以及侏罗系中低成熟煤成凝析油气藏。库车晚期—西域期是库车坳陷气藏的主要形成时期，主要形成高—过成熟气藏以及少量次生油藏，最近发现的克拉2 大气田以及克拉3 、大北1 、依南2 、吐孜1 等气藏均属该时期成藏。

There are many sedimentary facies, which are alluvial fans, terminal fans, fandelta, braideddelta, meanderingdelta, lacustrine facies,lagoon and beach facies，in Cretaceous and Paleogene, Kuche DepressionTabei area, northern Tarim Basin. The lithology assemblages and sedimentary facies are different in north and south zone, also in the east, middle and west segmentation. The north zones are made up of coarse clastics, which are mainly fandelta. The south zones are composed of middle and fine clastics,which are mainly braideddelta. The differences are controlled by palaeostructure, palaeotopographical gradient, palaeoclimate and the distance to provenance.

塔里木盆地北部库车坳陷—塔北地区白垩系—古近系发育有冲（洪）积扇、终端扇、三角洲（扇三角洲、辫状河三角洲、正常三角洲）、湖泊、滨岸海滩、潮坪—潟湖等多种沉积相类型。研究区南、北带及东、中、西段在不同沉积演化时期发育的岩性组合、沉积相类型及沉积相平面展布规模方面也有明显差异，北带主体为粗碎屑沉积，发育扇三角洲沉积；南带沉积物粒级相对较细，主体发育辫状河三角洲，这种差异主要受当时古构造位置、古地形坡度、沉积物源远近及古气候控制。

Braided river delta is an important reservoir type in continental sedimentary basins and the potential exploration target for the future.Core,log,and geophysical data indicate that the braided river delta in the Jurassic Sangonghe Formation of Junggar basin was deposited in an environment with gentle slope and shallow water.As a result of continuous progradation from the north to the center of the basin,arenaceous-conglomeritic deposits in the delta showed typical progradational seismic reflectance signatures,large cross bedding,and non-continuous positive rhythm.Its characteristics of sedimentary subfacies and microfacies as well as the favorable areas for exploration of lithologic traps are also discussed in this paper.

辫状河三角洲是陆相沉积盆地重要的油气储集类型和今后油气勘探的重点对象.综合分析岩心、测井与地震资料,认为准噶尔盆地侏罗系三工河组发育的辫状河三角洲处于沉积坡度较缓的、沉积水体较浅的沉积背景,该辫状河三角洲不断地由盆地北侧边缘向盆地中央方向远距离前积,沉积了砂砾质的、发育大型交错层理和间断正韵律的、具有典型前积地震反射的进积型辫状河三角洲,进而论述了该三角洲的亚相和微相沉积特征以及有利的地层岩性圈闭勘探地区.

Baxigai Formation and Bashijiqike Formation are main reservoirs of Cretaceous in the north edge of Kuche Depression. In Cretaceous Period there are different types of delta sedimentary systems developed in different stages of the basin evolution. The main sedimentary systems include lacus-lacustrine delta sedimentary systems in Baxigai Period, fan-delta sedimentary systems in early Bashijiqike Period and lacus-braid-delta sedimentary systems in mid-late Bashijiqike Period. Vertically, the lower sandstone section of Baxigai Formation is of aggradational sequence in general, and the upper mudstone section shows as progradational sequence. The III section at the lower part of Bashijiqike Formation shows the evolution from progradational to aggradational sequence, and the II-I sections of the mid-up part shows as a coarsening up sequence as a whole. Laterally, the sedimentary facies in the north edge of Kuche Depression spread from east to west as a whole, and the sedimentary facies varies obviously from south to north bides. Based on research of the sedimentary facies, integrated with the analysis of tectonic movement and diagenesis, we believe that the sandstone of braided delta front is quality reservoir, and the reservoir around well KL2 is the best, and become worse both westward to well KL1 and eastward to well KL3.

库车坳陷北缘白垩系储层主要分布在巴西盖组和巴什基奇克组。白垩纪时期，库车坳陷发育了不同类型的三角洲沉积体系，巴西盖期为湖泊三角洲沉积体系；巴什基奇克早期主要为扇三角洲沉积体系；巴什基奇克中晚期主要为湖泊-辫状三角洲沉积体系。垂向上，巴西盖组下部砂岩段总体表现为加积序列，上部泥岩段整体表现为向上砂质增多的进积序列；巴什基奇克组下部第Ⅲ岩性段表现为进积-加积演化序列特征；巴什基奇克组中上部Ⅱ-Ⅰ段总体上构成一个向上变粗的进积序列。平面上，从巴西盖期至巴什基奇克晚期，库车坳陷北缘沉积相总体上呈近东西向展布，南北相带变化明显的特点。在沉积相研究的基础上，结合构造活动和成岩作用分析认为，研究区内白垩系巴什基奇克组中上部辫状三角洲前缘砂体为优质储层，以克拉2井区最好，向西至克拉1井，向东至克拉3井储层均变差。