内蒙古海拉尔盆地早白垩世含煤岩系层序地层与聚煤规律

利用煤田钻孔资料,对内蒙古海拉尔盆地下白垩统含煤岩系层序地层格架及聚煤规律进行研究。根据区域不整合面、下切谷砂砾岩体底面、古生物组合突变面及沉积相转换面等层序界面,将海拉尔盆地下白垩统含煤岩系划分为6个三级层序。铜钵庙组是盆地初始断陷阶段的产物;南屯组一段、二段是盆地快速沉降阶段,大磨拐河组一段、二段是盆地稳定拉张阶段,伊敏组是断陷萎缩阶段。盆地早白垩世含煤地层的煤层发育表现为东、北部好,中部次之,西南部差的特点;聚煤作用主要发生在伊敏组及南屯组二段,这2个时期构造沉降表现出间歇性、震荡性及多旋回性,保证了可容空间增加速率与泥炭堆积速率之间的平衡关系,从而形成了区域性的厚煤层。     

银额盆地天草凹陷下白垩统层序地层格架与油气分布

银额盆地天草凹陷是一个西断东超的箕状断陷.通过天草凹陷二维地震资料和单井岩性、古气候、电性及地层倾角等资料,建立了天草凹陷下白垩统层序地层等时格架,将下白垩统划分为1个一级层序,2个二级层序,3个三级层序.在三级层序地层体制下,通过对凹陷演化和基准面旋回的分析,建立相应的断陷层序地层模式,预测了巴音戈壁组和苏红图组油气分布,指出了天草凹陷油气储集的有利相带.     

海拉尔盆地呼和湖凹陷下白垩统成煤环境

从构造和充填序列的角度分析了呼和湖凹陷下白垩统成煤环境,为该凹陷煤炭资源开发提供指导。呼和湖凹陷下白垩统主要经历伸展断陷和裂后热沉降断坳2个构造演化阶段。其中伸展断陷阶段可划分为初始张裂阶段、断裂强烈拉张阶段和断陷快速沉降阶段;裂后热沉降断坳阶段可划分为断坳转换沉降阶段和断坳沉降阶段。根据断陷盆地充填序列组合特征,将呼和湖凹陷下白垩统自下而上确定为底部粗碎屑冲积物段（Fm）、湖相细碎屑沉积段（Lm）、含煤碎屑岩段和湖相段（Cm-Lm）、湖相细碎屑沉积段（Lm）、含煤碎屑岩段和湖相段（Cm-Lm）和含煤碎屑岩段（Cm）类型。将构造演化和填充序列结合起来,探讨了南屯组二段、大磨拐河组二段和伊敏组的成煤环境。南屯组二段沉积时期,煤层主要发育在断陷湖盆沼泽长期稳定发育的滨湖地带和废弃的辫状河三角洲上。大磨拐和组二段沉积时期,凹陷为断坳浅水湖盆,北部聚煤作用主要发育在扇三角洲砂体上,南部聚煤作用主要发育在湖泊沼泽长期发育的滨湖地带。伊敏组沉积时期,凹陷全面淤浅,浅水洼地成为主要的聚煤场所。     

海拉尔盆地查干诺尔凹陷下白垩统层序地层格架及沉积体系研究

依据岩芯、测井、录井和地震资料,以层序地层学理论为指导对海拉尔盆地查干诺尔凹陷下白垩统的扎赉诺尔群进行层序地层划分。扎赉诺尔群可划分为1个超层序,形成于凹陷断陷发育期,自下而上可划分为5个三级层序(Sq1、Sq2、Sq3、Sq4、Sq5)。进而在层序框架内对沉积体系类型和时空展布特征进行了分析。凹陷主要发育冲积扇、扇三角洲、湖底扇、滨浅湖和半深—深湖沉积体系,并且层序地层格架对各沉积体系分布具有控制作用。     

黑龙江东部下白垩统鸡西群层序地层划分与聚煤作用分析

依据钻孔及露头资料,对鸡西盆地下白垩统鸡西群层序地层进行了研究,共划分出1个Ⅱ级、3个Ⅲ级层序.Ⅱ级层序代表了鸡西盆地最大一次湖侵→湖退沉积,3个三级层序反映了三次低级别的湖侵→湖退沉积作用.在此基础上讨论了鸡西群的成煤作用特点,其中Ⅱ级层序湖侵背景下的Ⅲ级层序湖侵体系域聚煤作用最好;湖退背景下Ⅲ级层序湖侵体系域聚煤作用次之;低水位背景下Ⅲ级层序湖侵体系域聚煤作用较差,Ⅲ级层序低水位与高水位体系域聚煤作用最差.研究结果对探讨鸡西盆地早白垩世沉积、成煤作用具有重要意义.     

兰州-民和盆地河口群层序地层格架特征及盆地演化

兰州-民和盆地河口群形成于早白垩世,其间充填了巨厚的陆源碎屑物,碎屑物的组合内容和方式反映了冲积扇相、扇三角洲相、湖泊相沉积体系占主导。盆地地层层序具有退积型、加积型、进积型叠置的变化旋回,显示了全韵律的特点,代表了构造旋回幕的产物。根据盆地的发展演化特征和层序界面的确定,初步建立了盆地的层序地层格架,同时阐述了盆地的演化过程。     

海拉尔盆地乌南地区下白垩统火山碎屑岩孔隙结构特征与储层分类

海拉尔盆地乌南地区下白垩统储层的岩性主要为火山熔岩、火山碎屑岩和正常沉积岩。以往的储层研究均遵循根据岩性建立测井解释方法的思路。根据乌南地区储层同种岩性具有不同测井响应、不同岩性又具有相同测井的特征,采用压汞实验分析与岩心孔渗试油分析相结合,建立本区的实验室条件下的储层分类标准,并利用常规测井资料建立乌南地区测井储层分类标准。压汞实验资料与岩心孔渗试油资料显示研究区储层可以分为三大类(四小类):Ⅰ类储层的孔隙以溶蚀粒间孔为主,黏土矿物以分散式和内衬式充填;ⅡA类储层孔隙主要是熔蚀粒间孔和溶蚀粒内孔,黏土矿物以搭桥式或以内衬式充填;ⅡB类储层主要为溶蚀粒内孔,黏土矿物以搭桥式充填;Ⅲ类储层在铸体薄片中几乎观察不到有效的孔隙,黏土矿物堵塞孔喉。采用XD-N与DEN或CNL做交会图,能有效区分乌南地区储层类别,储层分类判别符合率达到88.9%。     

内蒙古查干凹陷下白垩统层序地层格架与沉积体系分布

充分利用岩性组合、岩心、测井、地球化学及古生物等响应,结合构造演化及地震反射特征,在查干凹陷下白垩统识别出7个三级层序界面,将其划分为6个三级层序和16个体系域。层序展布早期具有北薄南厚、东薄西厚的特征,晚期沉积中心北移,呈西厚东薄、北厚南薄的格局。在层序格架内,早期由于毛敦次凸的分割作用,凹陷东西两侧的沉积格局存在差异,总体以水下扇、扇三角洲和辫状河三角洲沉积为主;晚期毛敦次凸逐渐接受沉积,沉积了一套冲积平原、泛滥平原及河流相沉积。下白垩统由下而上发育3套生储盖组合,下部SQ1的低位体系域储层与水进域的泥岩盖层形成自生自储的生储盖组合;中部生储盖组合以SQ2的高位域及SQ3的低位域储层为主;上部组合储层主要为SQ4—SQ6碎屑岩及火山岩储层。     

海拉尔盆地贝尔凹陷下白垩统南屯组储集层特征

海拉尔盆地是大庆油田较大的含油气盆地之一,贝尔凹陷是盆地内最大的凹陷,属于海拉尔盆地贝尔湖坳陷的二级构造单元,同时也是该盆地最有潜力的勘探地区。其主要储集层为下白垩统南屯组、铜钵庙组砂岩、凝灰质砂砾岩和凝灰岩及基岩风化壳。其中南屯组储集层主要岩石类型包括火山碎屑岩、陆源碎屑岩及少量的火山岩,其储集层主要储集空间类型为粒间孔隙、粒内孔隙、填隙物孔隙、裂缝和溶蚀孔隙。其孔隙结构较差,喉道半径小,分布不集中,分选不好。受沉积相带、埋深压实作用以及次生孔隙的影响,贝尔凹陷储集层物性总体以中低孔、低渗为特征,储集层主要分布于贝西次凹、贝西单斜带、霍多莫尔断鼻带和苏仁诺尔以及苏德尔特断裂带。     

黑龙江省东部残留盆地群早白垩世沉积相特征及演化

黑龙江省东部残留盆地群早白垩世主要充填滴道组（裴德组）、城子河组（七虎林组和云山组）、穆棱组（珠山组）和东山组。沉积相以冲积扇相、（扇）三角洲相、湖泊相、海相等为主。沉积相研究结果表明,滴道组以冲积扇及（扇）三角洲粗碎屑沉积为主,并伴随有火山岩分布,反映了盆地初始裂陷阶段的沉积环境特点;城子河组和穆棱组沉积时期,三江地区处于整体下沉阶段,现今残留的三江盆地、勃利盆地、鸡西盆地、虎林盆地、宁安盆地、鹤岗盆地和汤原断陷等为统一的近海拗陷盆地,张广才岭-小兴安岭及东三江和完达山地区是盆地主要物源供给区,平面上构成（扇）三角洲-滨浅湖-半深湖-湖底扇的沉积格局,并且伴随有多次海侵事件,海侵方向主要来自虎林盆地东部及绥滨坳陷北部;东山组沉积时期,盆地已明显萎缩,发育局限的（扇）三角洲-滨浅湖相沉积。     

Sporopollen Assemblages from the Cretaceous Yimin Formation of the Hailar Basin, Inner Mongolia, China

Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are （in ascending order）： the lmpardecispora-Aequitriradites- Clawttipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites- Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.     

Taxonomy and stratigraphy of Early Cretaceous species of Debrunia Masse and Fenerci-Masse (Hippuritida,Monopleuridae) of the Mediterranean region

The genus Debrunia is characterized by its myophoral organisation: the left valve posterior myophore is an erect plate, the anterior is a bulge or a crest, myophores of right valve are on shell wall, the ligament groove is inconspicuous and the cardinal apparatus tends to be shifted posteriorly. Shell habit varies from low conical to elongated cylindrical, and the shape of the left valve ranges from capuloid to flat. The taxonomic revision of Debrunia species of the Mediterranean regions reveals the presence of thirteen species, among which seven are described as new. Multiple Component Analysis and Cluster Analysis document the existence of five groups of species in correspondence with the height of the left valve and the commissural diameter. The longevity of Debrunia is high, 32 Myr, whereas its species have shorter durations which account for a significant biostratigraphic potential within the Valanginian–Albian time span. Debrunia has its FO (First occurrence) in the lower Valanginian and its LO (Last occurrence) in the Albian. Its developmental phase starts in the Hauterivian, marked by an increasing species diversity and a biogeographic expansion; and peaks in the late Barremian, followed by a collapse in diversity and a specific turnover, coeval with the “Agriopleura extinction event”. The mid-Aptian crisis is expressed by a drastic decline in species diversity, controlled by the overall restriction or demise of carbonate platforms in European regions. As elevators, Debrunia species tend to build dense monospecific aggregations and some of them possess a remarkable bioconstructional potential. The contribution of Debrunia to rudist communities is significant throughout the history of the genus.     

内蒙古平庄盆地层序地层与聚煤规律

利用平庄盆地钻孔和矿井地质资料,结合野外地质调查等工作,运用沉积学、层序地层学及煤田地质学的基本理论和方法,根据古构造运动面和大面积侵蚀面,将平庄盆地含煤岩系--杏园组和元宝山组划分为1个超层序和2个层序,并把层序划分为低水位体系域(LST)、湖泊扩展体系域(LTST)、湖泊萎缩体系域(LCST)和非湖泊体系域(NLST)。总结出层序地层与聚煤规律的关系是:LST和LTST基本无聚煤作用发生;LCST局部有利地段可发育薄煤层,但无工业利用价值;NLST聚煤条件最有利,常形成厚煤层。     

北祁连-酒西地区早白垩世盆地沉积特征与古地理演化

北祁连-酒西地区早白垩世沉积盆地(群)充填物、古流向和沉积环境等方面的调查研究认为:早白垩世在拉张-伸展的背景下形成了南抵中祁连山,北至北山地区,东达酒东盆地,西到阿尔金断裂带以西的泛北祁连-酒西盆地.盆地充填物表现出粗-细-粗的完整沉积旋回,古地理环境经历了冲积扇-河流-湖泊-河流的演变过程,并对应着湖盆从初始扩张-...     

Cretaceous sedimentary basins in Sichuan,SW China: Restoration of tectonic and depositional environments

This study documents sediment infill features and their responses to the tectonic evolution of the Sichuan Basin and adjacent areas. The data include a comparison of field outcrops, well drillings, inter-well correlations, seismic data, isopach maps, and the spatial evolution of sedimentary facies. We divided the evolutionary history of the Sichuan Cretaceous Basin into three stages based on the following tectonic subsidence curves: the early Early Cretaceous (145–125 Ma), late Early Cretaceous to early Late Cretaceous (125–89.8 Ma), and late Late Cretaceous (89.8–66 Ma). The basin underwent NW–SE compression with northwestward shortening in the early Early Cretaceous and was dominated by alluvial fans and fluviolacustrine sedimentary systems. The central and northern areas of the Sichuan Basin were rapidly uplifted during the late Early Cretaceous to early Late Cretaceous with southwestward tilting, which resulted in the formation of a depression, exhibited southwestward compression, and was characterized by aeolian desert and fluviolacustrine deposits. The tectonic framework is controlled by the inherited basement structure and the formation of NE mountains, which not only affected the clastic supply of the sedimentary basin but also blocked warm-wet currents from the southeast, which changed the climatic conditions in the late Late Cretaceous. The formation and evolution of Cretaceous sedimentary basins are closely related to synchronous subtle far-field tectonism and changes in climate and drainage systems. According to the analysis of the migration of the Cretaceous sedimentation centers, different basin structures formed during different periods, including periods of peripheral mountain asynchronous thrusting and regional differential uplift. Thus, the Sichuan Cretaceous sedimentary basin is recognized as a superimposed foreland basin.     

海拉尔盆地红旗凹陷早白垩世构造特征与变形期次的厘定

海拉尔盆地是叠置于内蒙-大兴安岭古生代碰撞造山带之上的中-新生代盆地,总体上呈北东向展布,由三坳、两隆5个一级构造单元组成,自西向东依次为扎贲诺尔坳陷、嵯岗隆起、贝尔湖坳陷、巴彦山隆起和呼和湖坳陷, 其中红旗凹陷是位于贝尔湖坳陷北部的一个二级构造单元。研究表明,红旗凹陷在早白垩世经历了4个变形阶段：在早白垩世兴安岭群-南屯组沉积时期为NW-SE向伸展作用阶段,形成以大型犁式正断层为控陷断层的NE向箕状半地堑;在大磨拐河组-伊敏组一段沉积时期为NW-SE向挤压作用阶段,使早期控陷正断层发生强烈的反转作用而转化为逆断层,靠近控陷断层的NW边界由于断层上盘的逆冲而隆升,凹陷的SE斜坡带由于控陷断层在反转作用过程中深部的逆冲滑移在浅部受阻而发生的旋转式隆升,使凹陷的规模发生明显萎缩,并在凹陷的中部形成大型NE向断层转折褶皱,构成了红旗凹陷的中部断隆带;在伊敏组二段下部沉积时期为近EW向伸展作用阶段,早期控陷断层表现出正断层的特征,新形成的NE向控陷断层具有左行离散型走滑的性质;在伊敏组二段上部沉积时期为近EW向挤压作用阶段,早期控陷断层再次表现为上盘逆冲的特征,在断层上盘、靠近断层的部位形成反转背斜,并在凹陷中形成断层转折褶皱。在每一变形阶段中,红旗凹陷的构造特征在空间上存在一定的差异。