松辽盆地北部上白垩统嫩江组二 、三段物源分析

通过岩芯观察描述以及分析化验资料的综合分析, 从岩石矿物成分、砂体平面展布、重矿物组合以及锆石-电气石-金红石指数(ZTR 指数) 、泥岩颜色区域分布等方面对物源方向进行了判断。综合分析表明: 松辽盆地北部嫩江组二、三段沉积时期物源随时间变化有所变化, 但变化不大。嫩江组二段沉积时期物源主要来自东方; 嫩江组三段沉积时期物源除东部来的物源外, 东北部物源对盆地北部物源体系也参与贡献, 物源的变化可能是由于嫩二段晚期盆地北部地层隆起。松辽盆地北部在嫩江组二、三段时期主要存在着 3 个方向的物源: 东北、东部以及西部物源。嫩江组二、三段沉积时期, 东部物源为主要物源, 在嫩江组三段沉积的中后期, 东北向物源出现并与东部物源共同起主导作用。西部物源在嫩江组三段沉积的中晚期出现, 影响范围小。     

松辽盆地白垩纪青山口组地质时代探讨

摘要 松辽盆地白垩纪青山口组赋存有丰富的松花江生物群化石,生物地层学研究表明其时代属晚白垩世。青山口组黑色泥岩、页岩具有有机碳含量高,干酪根碳同位素正偏、重排甾烷含量低、普遍存在伽玛蜡烷生物标志化合物,代表了温室气候时间窗内古湖泊贫氧-缺氧环境条件下的沉积产物。而青山口组底部出现的Cranwellia, Lythraites, Complexiopollis, Borealipollis, Buttinia, Areicipites, Sabalpollenites等一些具重要时代意义的被子植物花粉,以及锆石U－Pb年龄也证实了青山口组底界已属Turonian期,而非Cenomanian期。     

Oxygen and carbon isotope records of calcareous nannofossils for the past 1 Ma in the southern South China Sea

Oxygen and carbon isotopic analyses have been carried out on calcareous nannofossils from ODP Site 1143 in the southern South China Sea. The results demonstrate that the δ18O values of calcareous nannofossils for the past 1 Ma vary systematically with those of planktonic and benthic foraminifera from the same site. But the average δ18O value of nannofossils is 1.869‰ higher than that of planktonic foraminifera, and is 3.855‰ lower than that of benthic foarminifera. There are systematic differences between the δ13C values of nannofossils, planktonic foarminifera and benthic foraminifera. The average δ13C of nannofossils is 0.756‰ higher than that of benthic foraminifera, and is 0.460‰ lower than that of planktonic foraminifera. The δ13C values of nannofossils exhibit a significant positive shift beginning near isotope stage 14 and lasting until stage 8. This study also finds that there is a close ralationship between the δ13C of nannofossils and the percentage of Florisphaera profunda. This implies that the δ13C of nannofossils can be used as an indicator of sea water surface paleoproductivity.     

松辽盆地嫩江组泥质三角洲沉积特征及沉积机理

通过对松辽盆地嫩江组岩芯资料、测井资料和地震资料处理和解释, 发现在松辽盆地大庆长垣地区嫩江组二、三段湖相泥岩层段中, 具有一定角度自东向西的前积结构, 地震剖面中底部同相轴表现为中强振幅、高连续反射、叠瓦状特征; 每个层序可分辨出4~6个主要由泥岩构成的前积层, 有的顶积层存在顶超现象, 延续性相对较差; 岩性组合中泥质组分含量高, 砂质组分含量低。经研究认为, 这种具有一定角度前积结构的富泥贫砂沉积是高悬浮载荷河流入湖而形成的泥质三角洲沉积。建立了嫩江组湖泊沉积环境中发育的泥质三角洲的沉积模式。     

Marine dinoflagellates from Lower Cretaceous Muling Formation of Jixi Basin,China and their palaeoenvironmental significance

Newly discovered marine dinoflagellates from the lower-middle parts of the Lower Cretaceous Muling Formation of the Jixi Basin, eastern Heilongjiang Province,China, were identified as Circulodinium cingulatum He et al.,C. attadalicum (Cookson et Eiscnack) Helhy, Palaeoperidinium cretaceum Pocock, Oligosphaeridium totum Brideaux and Sentusidinium sp. Most of these species are distributed in the marine Lower Cretaceous strata of Europe, North America,Africa, Australia and Asia. It demonstrates that a transgression occurred in eastern Heilongjiang Province during the deposition of the Muling Formation, which was previously considered to be a coal-bearing continental stratigraphic unit.The marine dinoflagellates indicated that the Muling Formation is Barremian in age. The Palaeogeographic framework of eastern HeUongjiang Province in Late Mesozoic era should be rebuilt through systematic facies analyses of the marine,paralic and terrestrial deposits.     

A kind of coccoid dinoflagellates-like fossils gives a new explanation of source of dinosterane in the Early-Middle Cambrian

The coccoid fossils covered with thick gelatinous envelop containing several gametes are discovered in gyps and salt deposits of Cambrian, H₄ well and chert bed of the base of Yuertus Formation (∈¹₁) of Xiaoerbulake Section. The fossils are described and compared with coccoid dinoflagellates. These fossils may be a coccoid life-cycle stage (vegetative cyst) of coccoid dinoflagellates. If this identification is correct, the coccoid dinoflagellates-like fossils could give a reasonable explanation of the dinoflagellate-specific biomarkers from Cambrian, H₄ well, Tarim Basin.     

New discovery on dinosaur fossils from Early Jurassic, Sichuan, China

An early and primitive sauropod dinosaur, Gongxianosaurus shibeiensis (gen. et sp. nov.), from Lower Jurassic Dongyuemiao Member of Ziliujing Formation in Shibei Village, Gongxian County, Sichuan Province, China is described, which is among Gongxian dinosaur fossils discovered in 1997. Except for skull incomplete, fossils were well-preserved. It has concurrently some features of both sauropod and prosauropds. It is an intermediate type of evolution from prosauropod to sauropod, provides practical materials for studying of origin and evolution of sauropod dinosaur fauna, and a favourable way for stratigraphic correlation between Early Jurassic Ziliujing Formation and Lower Lufeng Formation, in the Sichuan Basin and the Central Yunnan Basin that lies to its southwest.     

Discovery of fossil monocotyledons from Yixian Formation, western Liaoning

This is the first reports of a few fossil monocotyledons, includingLiaoxia chenii gen. et sp. nov. (belonging to Cyperaceae),Eragrosites changii gen. et sp. nov. (Gramineae) and a monocotyledonous leaf-shoot, obtained from the Late Jurassic Yixian Formation of western Liaoning Province, NE China. These fossils are the oldest known angiosperms in the world. It may be inferred that the earliest angiosperms probably appeared even earlier than the Late Jurassic.     

松辽盆地油页岩勘探开发有利区预测

松辽盆地油页岩资源储量巨大且分布广泛,主要赋存于上白垩统青山口组一段和嫩江组一段、二段,含油率中等,一般为4.7%～5.1%左右。从松辽盆地油页岩地质特征及时空分布出发,选取主采层厚度和矿体埋深参数,建立油页岩段和盆地的优选标准,建立松辽盆地勘探开发有利区优选体系,将其划分为最有利、有利、较有利和一般有利4个级别的油页岩勘探开发区。其中,南起伏龙泉-农安,经增盛,北至肇源的地区为下一步勘探开发的靶区。     

Zircon SHRIMP U-Pb dating of meta-diorite from the basement of the Songliao Basin and its geological significance

Located in the east portion of the North Orogenic Belt, the Songliao Basin is bounded by the Da Hinggan Mountains in the west, the Xiao Hinggan Mountains in the north, the Zhangguangcai Range in the east, and the North China Craton (NCC) in the south (Fig…     

柴达木盆地西部第三系碳酸盐岩层的古生物特征

柴达木盆地西部第三系的碳酸盐岩层中发现有藻类、介形虫、有孔虫、腹足类、多毛类等化石.除藻类外各种生物的数量都比较少.生物具有个体小,壳体构造简单,多样性低等特点.所有生物都属于广盐性生物.根据该区古生物特征分析和与其它地区的对比,认为当时该区生物生长于内陆半咸化湖至咸化湖环境,而不是海相或海陆过渡相环境.参11.     

齐家地区高台子油层致密化与油气充注的关系

为了明确松辽盆地齐家地区高台子储层致密化与油气充注的关系，综合采用铸体薄片、扫描电镜、纳米CT、压汞实验、流体包裹体、恢复压实曲线等方法，对高台子致密储层微观特征进行了详细描述，并对致密储层成藏期进行了精细刻画，最后结合储层孔隙演化特征对该地区致密化过程与原油充注关系进行了探讨。结果表明，齐家地区高台子致密储层岩石类型以岩屑长石砂岩为主，其次为长石岩屑砂岩，储层孔隙类型主要为残余粒间孔和溶蚀孔，孔隙主要为亚微米-纳米级孔隙，孔喉连通性较好。储层致密时间在明水早期。该地区高台子油层存在两期油充注：早期原油充注发生在79~75 Ma，对应嫩江晚期；晚期原油充注发生在69~65 Ma，对应明水晚期。松辽盆地齐家地区高台子储层具有多期成藏且边成藏边致密特征。     

A new discovery of macroscopic fossils from the Ediacaran Doushantuo Formation in the Yangtze Gorges area

The Ediacaran section in the Yangtze Gorges area, South China, is one of the most important in the worldand contains abundant fossils[1-4]. The earliest discov- ery of macrofossils in 1984, including macroscopic algal fossils from the uppermost Doushantuo…     

A deep-bodied ginglymodian fish from the Middle Triassic of eastern Yunnan Province, China, and the phylogeny of lower neopterygians

The Ginglymodi are a group of ray-finned fishes that make up one of three major subdivisions of the infraclass Neopterygii.Ex- tant ginglymodians are represented by gars,which inhabit freshwater environments of North and Central America and Cuba.Here, we report the discovery of well-preserved fossils of a new ginglymodian,Kyphosichthys grandei gen.et sp.nov.,from the Middle Triassic(Anisian)marine deposits(Guanling Formation)in Luoping,eastern Yunnan Province,China.The discovery documents the first known fossil record of highly deep-bodied ginglymodians,adding new information on the early morphological diversity of this group.The studies of functional morphology of extant deep-bodied fishes indicate that Kyphosichthys is not a fast swim- mer but has a good performance in precise maneuvering,representing a morphological adaptation to structurally complex habitats (e.g.thick macrophyte beds,rocky areas,or coral reefs),which differs from the other members of this group.A cladistic analysis with the new fish taxon included supports the hypothesis that the Ginglymodi are more closely related to the Halecomorphi than to the Teleostei.Represented by Felberia,Kyphosichthys,and Dapedium,a highly deep and short fish body type has inde- pendently evolved at least three times in the stem-group neopterygians,ginglymodians,and basal teleosts within the lower neop- terygians of the Triassic.     

Discovery of marine fossils in the upper part of the Permian Linxi Formation in Lopingian, Xingmeng area, China

Two important geological issues have a long history of debate in the Xingmeng area. The first concerns the final closure of the North China plate, Siberia plate and several intermediate massifs in the area, and the other con- cerns the folding and lifting of the Xingmeng Trough. Dis- agreements arise because of issues involving the tectonic- palaeogeographical environment of the Upper Permian deposits of the Linxi Formation. The Linxi Formation （Upper Permian） is generally considered to be either an exclusively continental deposit or separated into marine- terrigenous facies deposited during the Lower to Middle Linxi Period and continental deposits in the Upper Linxi Period. However, in this study, large numbers of bryozoan and sponge spicule fossils were discovered for this first time in the thick limestone layers and lenses of the upper part of the Linxi Formation found in the Guandi section of Linxi county in eastern Inner Mongolia. At the same time, abun- dant bryozoan fossils were also found in sedimentary tuff slices that were collected from the upper part of the Tao- huayingzi Formation from the Taohuayingzi section in Ar Horqin Banner, and abundant small connecting body crinoid stem fossils were found in the dark shale of the Yangjiagou Formation from the Yangjiagou section of Jiutai county, Jilin Province. These marine fossils provide the first evidence that the Xingmeng area was still a marine or mainly marine environment at the end of the late Permian. This not only provides conclusive evidence for the recognition of the above two major geological issues but also promotes chan- ges in the approach towards research, exploration and development of oil and gas, shale gas （oil）, and other mineral resources that are preserved in the late Permian layers of the Northeast-Xingmeng area.     

The discovery of Jurassic plants in Shenzhen of Guangdong,southern China and related significance

Investigations of major marine and non-marine geologic and biotic events across the Triassic-Jurassic transition rely predominantly on detailed stratigraphic frameworks and biodiversity analyses. The alternating sequences of marine and terrestrial Triassic-Jurassic for- mations in Guangdong Province represent one of the most remarkable coal-bearing series in southern China. The Lower Jurassic Jinji Formation is widely distributed in Guangdong, with continuously outcropped sections and rich marine and non-marine fossil fauna. However, as little research has been conducted on fossil plant remains in the Jinji Formation, it is difficult to understand the systematics, diversity, and floral aspects of the Jurassic. Here we report on the recent collection of rich fossil plants from the Jinji Formation in the Dapeng area of Shenzhen, southern Guangdong Province. Our studies demonstrate taxonomical affiliations, preservation status, and diversity features of these plant fossils, which are marked by the close associ- ation of densely preserved, pinnae and rachis connected leaves, and the bennettitalean reproductive organs of Wil- liamsoniella, which may represent an Early Jurassic plant community dominated by Otozamites of the bennettitales. This work not only represents the first discovery of fossil plants in the Shenzhen area, but is also the first docu- mentation of Jurassic plants in Guangdong and the Pearl River Delta regions. Research related to these plant fossils will be helpful in the correlation of the Early Mesozoiccoal-bearing strata in Guangdong, and will provide a dee- per understanding of variations in plant diversity of the Triassic and Jurassic transition in southern China. Addi- tionally, it will provide terrestrial plant evidence for explorations in Jurassic palaeoecology, palaeoclimatology, and palaeogeography of southern China.     

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0.3?1.4 mm wide; their wrinkled lamellae are microfine with 3?10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965). The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.     

内蒙古平庄盆地中新世早期植物群与古环境

内蒙古平庄盆地晚第三纪植物群以被子植物占优势,计有16属22种,其次为裸子植物,6属7种,没有发现蕨类植物。其中裸子植物以杉科为主,被子植物以壳斗科、杨柳科、桦木科和榆科为主,连香树科、木兰科也有一定属种。该植物群总体面貌与吉林敦化秋梨沟植物群、山东山旺植物群和铁匠沟老梁底组的植物组合基本相似,时代为中新世早期。分析植物群组成特征及沉积特征,平庄植物群反映的是温暖湿润的暖温带－亚热带气候条件。     

吉林松辽盆地白垩纪油页岩资源及成矿特征研究

吉林省松辽盆地是我国重要的油页岩成矿区。油页岩层位主要赋存于白垩系的青山口组和嫩江组中。油页岩主要分布于青山口组一段和嫩江组一、二段地层中。温湿的气候条件、大量的藻类和浮游动植物,以及介形虫、植物等为油页岩的形成提供了有机物源。对松原地区油页岩的45个岩芯样品进行分析。嫩二段 TOC 平均值约为7.00%,高于嫩一段的5.80%。嫩一段的含油率平均值高于含油率为4.60%的嫩二段。青一段油页岩的 TOC 平均值为7.60%,含油率平均值为5.10%。     

松辽盆地南部西斜坡层序格架内油气成藏特征

松辽盆地南部西斜坡泉四段-嫩一段可划分为6 个三级层序、18 个体系域。通过对烃源岩、储层、盖层、圈闭
类型和油气输导与运移等成藏要素的综合分析,指出油气主要来自于中央凹陷区烃源岩,并具有厚度大,丰度高的特
点;储层以辫状河三角洲前缘相砂体为主,厚度大、物性好,属于中孔-中渗、高孔-高渗型储层;广泛发育的SQn1
泥岩是西斜坡的区域盖层;圈闭以构造圈闭、复合圈闭和地层-岩性圈闭为主;西斜坡油气分布具有明显的油气运移
转折带,油气在转折带以西以侧向运移为主,而在转折带以东以阶梯式运移为主。依据西斜坡地质条件差异与油气成
藏特点,划分出3 个有利区带,并总结了各自的成藏模式,分别为以“近源供烃、断层垂向输导、阶梯式成藏”模式为主
的SQy 三角洲前缘带与SQqn3 坡折带,及以“远源供烃、砂体侧向输导、有效圈闭成藏”模式为主的SQy 盆缘超覆带。