德阳须家河组四段沉积相特征和砂体分布规律

孝泉—新场—合兴场地区上三叠统须家河组四段以发育扇三角洲沉积体系为主,其砂体成因类型为扇三角洲前缘水下辫状分流河道(含砾)中—粗粒砂岩夹少量碎屑流沉积砾岩。须家河组四段可划分为1个长期、3个中期和18个短期基准面旋回层序,主要砂体合并为6套砂组。各砂组分布与由基准面变化引起的可容纳空间和沉积物供给量比值密切相关:低位体系域沉积期,基准面上升缓慢,沉积物供给(远)大于可容纳空间,沉积作用以主动进积为主,砂体不断向湖盆方向推进;湖侵体系域沉积期,基准面快速上升,沉积物供给量逐渐减少而(远)小于可容纳空间,沉积作用由进积逐渐转入加积和退积;高位体系域沉积期,基准面由缓慢上升逐渐进入到快速下降,可容纳空间由缓慢增加突变为迅速减小,而沉积物供给由小于或略等于可容纳空间逐渐变为(远)大于可容纳空间,沉积作用由弱进积、加积迅速变为强迫进积。     

川西上侏罗统遂宁组沉积相特征

川西地区在晚侏罗世遂宁期处于稳定坳陷阶段,构造活动相对较弱,主要沉积一套稳定的鲜紫红色泥（页）岩夹长石岩屑细-粉砂岩地层,构成了一个相对独立和完整的沉积旋回。根据不同级次基准面旋回分析,川西遂宁组可划分出1个长期层序、3个中期层序（对应于遂宁组的3个岩性段）和十余个短期层序。以各中期层序的上升和下降相域为编图单元编制的沉积相图表明：遂宁期川西地区以广泛发育被湖湾分隔的曲流河三角洲沉积体系为特征,并形成各自相对独立的储、盖组合和油气聚集成藏条件。遂宁期沉积演化具明显受基准面旋回控制的继承性,遂宁期早期（遂宁组一段沉积时期）,基准面不断上升,沉积作用以进积→加积为主,沿龙门山前缘发育有小型冲积扇或带状剥蚀区,向前分别在丰谷、新都、回龙镇各发育1套大且稳定的三角洲;遂宁期中期（遂宁组二段沉积时期）,随着基准面由缓慢上升转为下降,沉积作用由加积→退积→加积演化,遂宁期早期形成的3个三角洲分裂成4～5个发育较均衡的三角洲;遂宁期晚期（遂宁组三段沉积时期）,随着基准面不断下降,沉积作用由加积→进积演化,三角洲不断向湖推进,同时,由于受陆源物质供给不均衡的影响,该时期川西地区三角洲发育有较大变化,除在德阳发育1个较稳定的三角洲外,在新都发育的三角洲逐渐消亡,而在新津则由浅湖沉积逐渐演变为大型三角洲沉积。     

东营三角洲沙河街组三段中亚段地层格架初步研究及油气勘探意义

对于横向沉积为主的地层,三维地震资料在建立井间对比关系方面具有重要的作用。依据三维地震资料和钻井资料的综合解释,较好地确立了东营凹陷东部沙三中东营三角洲的高分辨率地层格架。东营三角洲沙三中层序是由沉积控制的等时地层单元,由下部较薄的加积单元和上部较厚的进积单元组成。通过对三角洲前缘中厚层泥岩的研究,高位体系域中可以识别出 6个准层序,每个准层序表现为前积叠置的、代表着一个或多个三角洲朵状体组成的层组。东营三角洲层序极不对称的垂向地层关系主要与在多级层序格架中的位置和控制层序及其体系域形成的主要因素-亦即沉积物供应量的变化有关,"敞流"湖盆的背景及相对稳定的缓坡构造活动条件扩大了沉积作用对地层结构的影响。同样,高位体系域形成时期高频的沉积物供应变化是准层序形成的主要原因。东营三角洲沙三中等时地层格架的探讨对古代湖盆三角洲的研究,及伴生的浊积岩岩性油气藏的预测、描述和勘探都具有重要的意义     

库车坳陷东部山前带古近系不同体系域内扇三角洲沉积砂体的对比研究

通过对塔里木盆地库车坳陷南天山山前带克孜勒努尔沟与依奇克里克野外露头沉积相的精细研究,结合山前带大量地震剖面分析与迪那201井、东秋5井等多口钻井测井相和岩心精细描述,将古近系库姆格列木群划分为2个层序。层序2低位域以冲积扇沉积为主,自湖侵体系域始,研究区广泛发育退积与进积型扇三角洲沉积。库姆格列木群层序2湖侵体系域内扇三角洲平原砂体以正韵律沉积为主,砂砾岩占地层厚度的(68.4～87)%;扇三角洲前缘砂体正、反韵律均有分布,砂砾岩占地层的百分比有所降低,为(55.2～77)%。高位体系域内主要发育以反韵律砂体为主的扇三角洲前缘沉积。古近系苏维依组只发育一个层序,其低位体系域的砂体为扇三角洲平原与前缘的分流河道砂体,湖侵体系域内扇三角洲前缘砂体正、反韵律均发育,高位体系域内主要发育扇三角洲前缘沉积,以反韵律砂体为主,正韵律砂体相对较少。对比苏维依组不同体系域内砂体储集性,湖侵域内砂体优于高位域内砂体。扇三角洲沉积体中有利储集砂体首选为湖侵体系域内的扇三角洲前缘水下分流河道和河口坝砂体,次之为低位域扇三角洲前缘(平原)分流河道砂体,最后是高位域内的河口坝及席状砂沉积砂体。特别要指出:低位体系域或者湖侵体系域底部发育的扇三角洲前缘(平原)分流河道砂体(底砂砾岩)被快速湖侵的较厚的暗色泥岩所覆盖,可形成较好储集场所。     

松辽盆地白垩系非海相沉积层序模式

本文阐述了层序地层学在松辽盆地应用的主要依据,总结了白垩系层序地层的基本特征。归纳出层序边界的识别标志。在岩芯中层序边界附近见古土壤或根土层、河床滞留砾岩、水进滞留砾岩、水下滑塌、钙质结核及相突变现象,层序边界之上覆盖风暴岩、三角洲前缘席状流沉积、冲积扇、鲕粒灰岩、生物屑灰岩、物性良好的砂岩和火山岩。层序边界的测井响应特征为退积/前积渐变型、退积/加积突变型、加积/前积型、前积/前积型等。在地震剖面上,层序边界处见削截、上超、顶超等反射结构。根据地震、测井和岩芯资料的综合解释,重点论述了主要含油层系的体系域特征,由此提炼出松辽盆地白垩系层序地层理想模式。低水位体系域由滞后平衡表面之下的冲积扇、河口砂坝、“下切谷”充填物、滑塌、碎屑流沉积、浊积岩及三角洲前缘席状流沉积组成;水进体系域发育风暴岩、砂滩、砂坝、三角洲前缘席状砂、叠层石和碳酸盐浅滩;典型的密集段形成于海泛期,赋存于水进体系域顶部和高水位体系域底部;高水位体系域主要有三角洲、扇三角洲和曲流河体系组成。经对比,松辽盆地与海相基准面变化的二级旋回趋近,但三级旋回高于后者。     

鄂尔多斯盆地长北气田山西组2 段高分辨率层序构型与砂体预测

以钻井测井、岩芯描述和样品分析为基础,高分辨率层序分析为技术方法对鄂尔多斯盆地长北气田山西组2段进行了精细的沉积相和层序分析,将山2段确定为海相辫状河三角洲沉积体系,并将其划分为1个长期、2个中期、4个短期和9个超短期基准面旋回层序和2大类5种基准面旋回结构类型。分析了不同级别基准面旋回层序的叠加式样与砂体展布和演化规律,建立了以中期基准面升、降半旋回相域为等时地层单元的山2段地层格架和对单砂层进行了等时追踪对比,确定中期上升期是三角洲河道砂体连续叠置形成巨厚砂体的最有利时期,洪泛期为细粒沉积物沉积期,也是隔层和局域性盖层主要发育期,下降期受侵蚀影响河道砂体不发育。以高分辨率层序分析为基础,建立等时地层格架为约束条件,结合单砂体为等时地层单元编制砂岩等厚图、砂/泥比等值线图和沉积微相图,对长北气田山2段砂体分布开展序贯指示三维模拟和预测,为长北气田山2段气藏高效开发提供依据。     

松南海坨子—大布苏地区泉四段— 姚家组层序地层研究

根据工区内现有的钻井、测井和地震资料,应用以多级次基准面旋回为参照面的高分辨层序地层学理论与研究方法,对松辽盆地南部海坨子—大布苏地区的泉四段—姚家组地层进行了详细的层序地层研究,共识别出5个长期基准面旋回（相当于三级层序）,9个中期基准面旋回（相当于四级层序）,建立了研究区的层序划分方案,在连井剖面的层序地层对比基础上,建立了该区的地层格架,并对层序构成特征进行了分析,研究了储集层在层序格架内的分布规律,揭示出浊积砂体和三角洲前缘相的分流河道形成于基准面上升期,三角洲前缘相的河口坝、远砂坝和席状砂沉积形成于基准面下降期,指出浊积砂体和三角洲前缘相的远砂坝、席状砂沉积是研究区形成岩性油气藏的有利储集体。     

松辽盆地北部葡萄花油层隐蔽油气藏分布规律

松辽盆地北部姚家组一段中的古土壤层可作为层序地层划分的依据.在姚家组一段中识别出3个不整合面,由盆地边缘向中心分别以河流侵蚀面-古土壤层-强烈生物作用面为标志,其下部为进积型的低位体系域三角洲砂质沉积,中部为退积型的水侵体系域三角洲砂质沉积,顶部为以泥质岩为主的加积型高水位体系域平原淤积相沉积,构成了完整的储盖组合.本文建屯了受平缓坡折控制平坦古地貌背景下的大型陆相坳陷盆地层序地层学模式,认为坡折带控制岩性油藏分布,坡折带以下广泛分布的三角洲砂体成为大面积岩性油藏储集体.坡折带附近的近源区发育多层位三角洲砂岩复合体,形成了多层、厚层岩性油藏,远离坡折带的远源区分布着大面积的三角洲外前缘砂体,可形成砂岩透镜体岩性油藏和上倾尖灭岩性油藏.     

鄯勒油田西山窑组层序地层格架及其油气地质意义

运用层序地层学的基本原理和技术方法,建立鄯勒油田西山窑组层序地层格架,划分沉积相,并在此基础上分析层序地层格架内砂体的展布特征和油气的聚集规律,预测研究区岩性油气藏的类型及分布。研究结果表明：西山窑组整体经历了一个先进积、后退积的过程;西山窑组为一个三级层序,其中包含2个四级层序,该组由低位域（LST）的三角洲前缘沉积、湖侵域（TST）的三角洲平原沉积和高位域（HST）的湖相沉积组成。研究区基准面上升期可以寻找砂体上倾尖灭型岩性圈闭,基准面下降期可以寻找砂岩透镜体岩性圈闭。西一、二段沉积的三角洲河道砂体受后期构造运动的影响,可以形成砂体上倾尖灭型岩性油气藏;而西三、四段的湖相浊积砂体,可以形成砂岩透镜体岩性油气藏。     

苏红图-银根盆地下白垩统层序地层学研究

本文根据沉积、古生物及地震资料对苏红图-银根盆地下白垩统的层序地层学特征进行了研究。把下白垩统划分为１个三级层序和低水位体系域、湖侵体系域、高水位体系域。根据准层序的叠置方式，准层序组有进积型、退积型和加积型，本区下白垩统可以划分９个准层序组，以退积型准层序组最为发育。苏红图-银根盆地早白垩世早期沉积格局曾发生过显著变化，从早到晚先后发育冲积扇、扇三角洲、浅湖和深湖相沉积，并在深湖相暗色页岩中夹有浊流和泥石流沉积，为退积型湖进层序。早白垩世晚期则由滨浅湖相演化为滨湖沼泽和河流相沉积，为进积型湖退层序。本区的湖侵体系域浅湖-深湖相暗色泥、页岩厚度大，有机质丰度高，类型好，是重要的烃源岩。低水位体系域的扇三角洲层序以加积型为特征，即下部为扇三角洲平原，中部为扇三角洲前缘，上部为前扇三角洲。反映了该区处于活动盆地边缘，湖水由浅变深，扇三角洲相应后退，沉降速率大于沉积速率。其中扇三角洲前缘砂体的储集作用不可低估。高水位体系域的滨浅湖滩砂也是重要的油气储集体。而湖侵体系域的深湖相泥、页岩和高水位体系域的滨湖沼泽相泥岩均可作为区域盖层。它们在垂向上构成了有利的生储盖组合。     

Palaeozoic structural development along the Tornquist Zone, Kattegat area, Denmark

The interpretation of newly released commercial 2D reflection seismic data in the Kattegat area, Denmark, has provided us with a better understanding of the Palaeozoic tectonic processes along the Tornquist Fault Zone. A Base Palaeozoic time structure map, a Lower Palaeozoic TWT isopach map, a “true” Lower Palaeozoic TWT isopach map, an Upper Carboniferous/Lower Permian syn-rift TWT isopach map, a Top pre-Zechstein time structure map and a Zechstein combined TWT isopach and Palaeogeography map have been generated. The uniform Lower Palaeozoic sequence thickness in the Kattegat, both inside and outside the Tornquist Zone indicates only minor lateral movements if any, whereas the extensive Upper Silurian sequence, increasing in thickness to the north, indicates a relatively fast regional subsidence. The Base Palaeozoic time structure map and the Late Palaeozoic syn-rift isopach map show a clear Late Palaeozoic extension in the area. The syn-rift isopach map, in combination with the time-equivalent opening of the Skagerrak graben at right angles to the Tornquist Zone in the Kattegat, indicates that this extensional tectonic event had a dextral slip component. Measurements on internal extensional faults in the Tornquist Zone, give a minimum right-lateral displacement of 10.4 km. The footwall blocks were deeply eroded during the Early Permian rifting, and at Zechstein times the area became a peneplane. The Tornquist Zone was later exposed to several tectonic phases, where dextral slip played a role, indicated by the “push up” and “pull down” structures caused by restraining and releasing bends of the Børglum Fault. The dextral displacement along the Børglum Fault since the beginning of the Permian is in the order of 5–7 km based on the displacement of a Lower Palaeozoic local depocentre. Early Permian depocentres and faults, which gives a total amount of right-lateral displacement since the Early Palaeozoic in the order of 15–20 km. The continuously repeated tectonic episodes along the Tornquist Zone throughout most of the Phanerozoic, show that the zone was easily reactivated, implying deep-seated basement faults. The Tornquist Zone can be seen as a “buffer zone”, between continental blocks, whenever changes in the regional stress field are induced.     

新密煤田翟沟井田山西组煤层特征及聚煤环境分析

以新密煤田翟沟井田勘探资料为基础,对井田区域特征、山西组煤层特征和沉积环境进行分析。研究表明：山西组下段为以泥坪＋泥炭沼泽＋泥坪沉积序列为主的潮坪沉积,山西组上段为以弱还原环境河流作用为主的三角洲沉积体系,山西组聚煤环境为滨岸潮坪环境;山西组二。煤层层位稳定,煤层结构简单,煤层厚度为0．82-12．20m,一般3—5m,平均厚度3．84m,煤层厚度的变化是受沉积环境、后期冲刷作用及构造作用综合作用的结果。     

Evidence for synsedimentary differential tectonic movements in a low-subsidence setting: Early Jurassic in northwestern Switzerland

During the Early Jurassic (lasting?~?27 Myr) only thin deposits (mostly ca. 30–50 m) of the Staffelegg Formation accumulated in wide parts of NW Switzerland while sea-level rise was in the range of?~?60 m. Isopach and facies patterns provide clear evidence of differential subsidence while faults that formed in the basement during the late Palaeozoic became reactivated. Orientation of many relative thickness minima and maxima follows faults constituting either the Rhenish Lineament or the North Swiss Permo-Carboniferous Trough. Such pattern is seen on the isopach maps of the Schambelen, Beggingen, Weissenstein, Frick, Fasiswald, Mt. Terri, Breitenmatt, Rickenbach, Rietheim and Gross Wolf members of the Staffelegg Formation, independently upon if the individual lithostratigraphic units are condensed or display somewhat enhanced thickness. Onto a general trend of decreasing thickness to the S, often isopach anomalies of small areal extension are superimposed. They suggest that localized strike-slip movements affected a mosaic of basement blocks. Reactivation of faults in the basement during the Early Jurassic is also evidenced by temporally enhanced hydrothermal activity as documented by chronometric ages of veins and mineral alterations.     

天山乌鲁木齐河源一号冰川探地雷达测厚及其数据分析

探地雷达是一种利用电磁波的反射原理探测地下介质分布特征的地球物理勘探技术，在冰川研究中发挥了重要作用。在天山一号冰川上用探地雷达进行了探测，获得了能够清晰地分辨冰一岩界面的雷达剖面。根据这些雷达剖面读出冰厚值，再结合最新的冰川地形图，作出了天山一号冰川的冰厚等值线图和冰下地形图；并由天山一号冰川最新的表面积数据推算了冰储量。     

栖霞组和茅口组等厚图:对峨眉山地幔柱成因模式的指示意义

对峨眉山大火成岩省(ELIP)及周边地区的栖霞组和茅口组地层进行厚度统计,并利用Surfer软件分别绘制等厚图.栖霞组和茅口组等厚图表明,峨眉山地幔柱导致的隆升可能在栖霞期已开始.茅口组顶部普遍存在平行不整合界面,说明广大区域内的茅口组地层均曾抬升为陆并遭受剥蚀,与CampbeU和Griffiths提出的经典地幔柱模型相吻合.永仁-大姚-楚雄-石屏以及宜良-曲靖一带存在二叠系地层缺失区域,可能是地壳隆升幅度最大地区.利用实验模型推导出ELIP的最大隆升幅度为1500m,与前人利用沉积学推算的结果基本一致.茅口组差异剥蚀指示的地幔柱中心地区与放射状基性岩墙群收敛中心吻合.隆起幅度最大的中心区域存在海相玄武岩喷发现象则可能是隆升之后快速沉降造成的,并不能作为否定曾经发生隆起的证据.     

鄂尔多斯盆地西部晚三叠世构造属性探讨

有关鄂尔多斯盆地西部晚三叠世的构造属性问题,前人的观点大多认为该时期为(类)前陆盆地,笔者对此提出置疑,主要有3个方面的依据:首先,对西缘汝箕沟、石沟驿和崆峒山地区晚三叠世延长组的3套粗碎屑沉积进行了重新认识。汝箕沟延长组确实为边缘相沉积,但其附近层位板内玄武岩的出现,表明该区晚三叠世为拉张环境下的沉积。最新研究表明,石沟驿地区延长组沉积厚度并不大,不超过1500m。崆峒山砾岩沉积可能受西南部的秦祁造山带影响所致,不能作为盆地西部沉积的代表。其次,通过编制晚三叠世延长组地层等厚图及一系列东西向地层剖面对比,发现该时期以往认为的盆地西部从南至北的巨厚沉降带并不存在。最后,通过地震剖面、平衡剖面和裂变径迹测试数据分析,指出西部现今存在的横山堡后冲构造带和马家滩大型逆冲推覆构造带并未形成于晚三叠世,其最早形成于晚侏罗世。故鄂尔多斯盆地西部晚三叠世构造属性并非为前陆盆地,而是残延克拉通内叠合盆地的组成部分。该认识对盆地西部的油气勘探具有重要意义。     

河北省页岩气地质条件评价

应用泥页岩厚度、TOC含量、干酪根类型和成熟度等评价参数,对河北省主要的含暗色页岩系地层——中元古界长城系串岭沟组和蓟县系洪水庄组、新元古界青白口系下马岭组、古生界石炭二叠系太原和山西组、新生界古近系沙河街组的页岩气成藏地质条件进行评价,预测固安、霸县沙河街组和沧州、廊坊太原-山西组为页岩气有利勘探目标区。     

聚类分析在物源分析中的应用——以伊通盆地鹿乡断陷为例

鹿乡断陷近年来虽在油气勘探方面取得了一系列成果,但该区存在多物源方向交汇、沉积体系划分不清晰;而经典的物源分析方法操作复杂,可靠性差。笔者应用统计学方法,对研究区重矿物的相对含量进行聚类分析,结合研究区砂岩等厚图,对鹿乡断陷双阳组各段的物源方向进行分析,结果表明:在双阳组一段沉积时期,研究区存在西南、南部和东部3个物源方向;在双阳组二段沉积时期,研究区存在东部、南部、西南和西北4个物源方向;在双阳组三段沉积时期,研究区存在东部和西北部2个物源方向。双阳组沉积时期,西北和南部方向物源的沉积物供给呈现"弱--强--弱"的变化特点,东部方向物源的沉积物供给不断减弱。沉积体系的规模受控于沉积速率。     

Sediment thickness map of the Indian region 79°E–86°E, 2°S–8°S based on satellite gravity interpretation

Satellite free air gravity anomalies over the Indian ocean region 79°E–86°E, 2°S–8°S were obtained from the website http://topex.ucsd.edu and a contour map was compiled. Five profiles of the anomaly have been interpreted in terms of two-dimensional structures in the ocean. Thickness of sediments lying on the oceanic crust determined from the interpretation of gravity profiles were used to compile an isopach map of the region 79°E–86°E, 2°S–8°S. This map in combination with one of the isopach maps compiled by previous workers, provides information regarding the thickness of sediments up to 6° S. According to this map sediment thickness varies from ～600 m over the middle part of the region to ～800 m further south, indicating that thinning of sediments in the middle part of the region is only localized. Information provided by this gravity study may be useful in planning detailed seismological studies to delimit the outer edge of the continental margin of Sri Lanka, defined according to the United Nations Convention of the Law of the Sea (UNCLOS).     

Permo-Carboniferous coal measures in the Qinshui basin: Lithofacies paleogeography and its control on coal accumulation

The Qinshui basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China. The methane reservoirs in this basin are the Carboniferous and Permian coals. Their thickness is strongly controlled by the depositional environments and the paleogeography. In this paper, sedimentological research was undertaken on the outcrop and borehole sections of the Taiyuan and Shanxi formations in the Qinshui basin and the basin-wide lithofacies paleogeography maps for these two formations have been reconstructed. The Taiyuan Formation is composed of limestones, aluminous mudstones, siltstones, silty mudstones, sandstones, and mineable coal seams, with a total thickness varying from 44.9 m to 193.48 m. The coal seams have a thickness ranging between 0.10 and 16.89 m, averaging 7.19 m. During the deposition of the Taiyuan Formation, the northern part of the basin was dominated by a lower deltaic depositional system, the central and southern parts were dominated by a lagoon environment, and the southeastern corner was occupied by a carbonate platform setting. Coal is relatively thick in the northern part and the southeastern corner. The Shanxi Formation consists of sandstones, siltstones, mudstones, and coals, with the limestones being locally developed. The thickness of the Shanxi Formation is from 18.6 m to 213.25 m, with the thickness of coal seams from 0.10 to 10 m and averaging 4.2 m. During the deposition of the Shanxi Formation, the northern part of the Qinshui basin was mainly dominated by a lower deltaic plain distributary channel environment, the central and southern parts were mainly an interdistributary bay environment, and the southeastern part was occupied by a delta front mouth bar environment. The thick coals are distributed in the central and southern parts where an interdistributary bay dominates. It is evident that the thick coal zones of the Taiyuan Formation are consistent with the sandstone-rich belts, mainly located in the areas of the northern lower deltaic plain and southeastern barrier bar environments, whereas the thick coal zones of the Shanxi Formation coincide with the mudstone-rich belts, located in the areas of the central and southern interdistributary bay environments. Translated from Journal of Palaeogeography, 2006, 8(1): 43–52 [译自: 古地理学报]