73 resultados para Permian-Triassic


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本论文系统回顾了无被果孢属的研究历史,讨论了无被果孢属的鉴定特征及种的划分依据,总结了无被果孢属已有种的特征及分布。在此基础上对山西太原西山煤田太原组7号煤层煤核及河北平泉杨树岭煤矿太原组火山凝灰岩中的无被果孢属进行了详细的解剖学研究,把它们与无被果孢属已有种进行了详细的对比后,共鉴定出二个新种和二个未定种。这二个新种的主要特征如下: 过渡无被果孢(新种)Achlamydocarpon intermedia sp. nov. 大孢子囊大约长6.0-10.0 mm,宽4.6 mm,高1.4mm,背腹扁状,具顶脊,两侧角明显, 近轴端开口。孢子囊壁复杂,分化为三层:最外层为单层柱状细胞层;中层1-2层细胞厚,细胞具深色内含物,壁薄;内层1-3层细胞厚,细胞壁强烈加厚。柱状层朝近轴端方向厚度加大。大孢子叶柄背脊不甚发育,具明显侧翼,侧翼的末端膨大并下垂使得柄的横切面略呈 “M”形。侧翼的宽度由近轴端向远轴端随孢子囊宽度的增加而增加,整体宽度大致保持为孢子囊的宽度的1/2左右。侧翼的近轴面具对称的厚壁组织区域。木质部束在近轴端为近等径状,向远轴端则变为略呈水平伸长状。通气组织发达,独立空腔结构贯穿孢子叶柄的整个长度。败育大孢子似乎具肿块结构。 本新种产于山西太原西山煤田太原组7号煤层煤核中。 2、平泉无被果孢(新种) Achlamydocarpon pingquanensis sp. nov 大孢子囊10.0-15.0 mm长,8.1 mm宽,3.0 mm 高。背腹扁,不具顶脊,两侧角明显,远轴端开口。壁复杂,分化为5层:最外层为薄壁细胞层,厚1-3层细胞;次外层为次生壁强烈增厚的细胞层,厚2-数层细胞;中层为具深色内含物的薄壁细胞层,厚2-数层细胞;次内层为与次外层相似的厚壁细胞层;内层为厚度达数个细胞的薄壁细胞层。孢子叶柄侧翼发育,宽度大于孢子囊宽度。背脊或龙骨很不显著。远轴面有时呈强烈的起伏不平状。大孢子囊底部与孢子囊柄连结部分由厚壁的细胞构成。不育组织垫结构较显著。功能大孢子扁缩,在近轴端发育较好,上表面具一突起结构。败育大孢子瘪缩,结构复杂,具明显肿块结构(?),瘤状肿块结构与败育孢子表面相连部分呈棒状。孢子叶柄近轴面不具有明显的厚壁组织区域;维管束由木质部束、维管束鞘及其所围成的空腔组成,但在远轴端仅剩下木质部束;通气组织发达,在维管束下方形成一独立空腔。 本新种分别产于山西太原西山煤田太原组7号煤层煤核和河北平泉杨树岭煤矿太原组火山凝灰岩中。 过渡无被果孢(新种)的特征介于欧美植物区的变异无被果孢类型和塔赫他间无被果孢类型之间。平泉无被果孢(新种)则与变异无被果孢类型较相近,但二者的大孢子囊壁的最外层完全不同:前者的是柱状细胞层,而后者的则由近等径的类似薄壁组织的细胞构成。二个未定种中,无被果孢(未定种 1)与过渡无被果孢(新种)很相似,区别在于前者的大孢子囊壁缺乏最外层的柱状细胞层以及孢子叶柄具明显的背脊或龙骨。无被果孢(未定种 2)则与塔赫他间无被果孢类型较接近。 根据华夏植物区和欧美植物区的化石材料和文献,探讨了保存不完整的大孢子囊-孢子叶复合体的远轴端和近轴端的判断方法:孢子囊较宽较高、孢子叶柄较为粗大、侧翼较发育、维管束较大、通气腔较发育的一端往往为远轴端,反之则为近轴端。 还讨论了无被果孢属一些构造的演化趋势: 1、孢子囊壁由简单向复杂或高度分化; 2、通气组织由不发达到高度特异化; 3、叶迹从微弱到显著,从简单到复杂; 4、败育大孢子从饱满到瘪缩,从表面平整到高度曲折,结构复杂化 5、大孢子四分体结合紧密度呈下降趋势

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辉木植物是莲座蕨目在晚古生代最重要的成员,广泛分布于当时处于热带-亚热带气候条件下的晚石炭世-二叠纪欧美植物区和华夏植物区。目前欧美植物区晚石炭世的辉木植物已经研究得非常深入和全面,但相对来说二叠纪的辉木植物的研究,尤其是关于其非茎器官的研究要薄弱得多。中国山西太原西山煤田早二叠世早期太原组7号煤层煤核中产有丰富的辉木植物各种器官化石,这就为深入了解二叠纪辉木植物的形态、解剖以及辉木植物的系统发育与演化提供了重要的化石材料。本论文利用国际上研究煤核时广泛采用的揭膜法,深入研究了山西煤核中2种分散保存的辉木植物器官:羽轴-山西枝蕨(新种)和生殖羽片-山西始莲座蕨(新种)。由于目前尚无有关二叠纪具解剖构造的辉木植物羽轴的详细研究的报道,因此,山西枝蕨(新种)是国内外目前为止第一种研究得最详细的二叠纪具解剖构造的辉木植物羽轴,它与欧美植物区枝蕨属已有的几个种(均为晚石炭世)的主要区别在于:前者为背腹扁状,后者则为两侧扁状;前者具较发育的鳞片,后者一般没有;前者的表皮下方有一条含有较大的单宁质细胞的薄壁组织带,后者没有;前者的内维管束呈“C”形,较大,位于正中央,后者的内维管束一般呈“W”形,较小,位于一侧。山西始莲座蕨(新种)是目前为止国内第一种(世界第二种)详细研究的二叠纪具解剖构造的两侧对称形的辉木植物聚合囊,同时也是目前国内发现的时代最早的华夏植物区两侧对称形的莲座蕨目聚合囊(包括印痕-压型化石和具解剖构造的矿化化石),它与欧美植物区始莲座蕨属已有的2个种(均为晚石炭世)的主要区别在于:前者的聚合囊囊托维管化,后者的囊托中无维管组织存在;前者的孢子囊侧壁细胞在近顶端呈明显的径向伸长状,后者的孢子囊侧壁细胞的形状和大小在孢子囊的上下没有很明显的变化;前者的孢子很小,数量多,纹饰简单,后者的孢子大,数量少,纹饰复杂。总的来说,本文所研究的二个新种与欧美植物区同属其它种之间的区别要大于后者彼此之间的区别,这可能是由于处于不同的植物地理区,经过长期地理隔绝和平行演化的结果。本研究成果不仅丰富了我们对二叠纪辉木植物非茎器官解剖构造的认识,而且对今后开展华夏植物区二叠纪辉木植物的分类、系统发育和演化以及整体植物的研究,都具有重要的作用和意义。

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本论文应用揭膜方法(Peeling Method)对产于我国西南地区滇东黔西一带晚二叠世地层中的保存有解剖构造的莲座蕨目化石进行了较为深入的研究,包括3 种茎和一种生殖器官。3 种茎中有二种为本文首次研究,均归入辉木属Psaronius Cotta,建立了二个新种:盘县辉木P. panxianensis 和老屋基辉木P. laowujiensis;另外一个种-田氏辉木P. tianii Li(MS)为前人所建立,但未正式发表,本文做了重新研究,新发现了一些特征,并对一些已有特征做了修订。讨论了这3 个种一些重要特征的分类和系统演化意义,这些特征包括:叶迹最后分出时的维管构型、维管束鞘和边缘茎维管束内侧的厚壁组织束。通过对不同地区和不同时代辉木属已有种的特征分析,对辉木属属下分类做了尝试,根据维管束是否结成环状、叶迹维管构型、是否具维管束鞘、边缘茎维管束内侧的厚壁组织束的发育与否、边缘茎维管束是否分叉等特征将辉木属已有种(包括本文所研究的3 个种)分为5 个组:1. Blicklei 组,代表种为Psaronius blicklei Morgan,包括欧美植物区目前已知各种,可能还包括华夏植物区的一些种。它们的主要特征是:不具维管束鞘;边缘茎维管束内侧的厚壁组织束不发育。2.Panxianensis 组,代表种为盘县辉木Psaronius panxianensis He,Wang,Hilton,Tian et Zhou,包括王氏辉木、老屋基辉木、江苏辉木,可能还有八角辉木和六角辉木。最主要特征是:具维管束鞘,简单,仅由薄壁细胞构成;边缘茎维管束内侧具树枝状和伞状或锚状厚壁组织束;叶迹由3 根维管束构成。该组目前仅发现于华南地区二叠系。3. Tianii 组,以田氏辉木Psaronius tianii Li(MS)为代表,目前只有这一个种。该组的主要特征:具维管束鞘,复杂,可分为两层;边缘茎维管束内侧具菊花状厚壁组织束,且每两环维管束之间具两条厚壁组织束,其中一条连续,另一条不连续;叶迹呈歪斜的弓形或M 形;叶迹维管束与茎维管束等粗;边缘茎维管束可分叉。该组目前仅发现于华南地区二叠系。4. Brasiliensis 组,以巴西辉木Psaronius brasiliensis Brongniart 为代表,除巴西辉木外,可能还包括P. sp. Herbst。该组的最主要特征就是其维管束的一端内卷并与主体部分连接形成一个封闭的环状构造;茎中央的维管束小,形态多变,而且排列十分不规则。该组目前仅发现于南美地区二叠系。5. Sinuosus 组,以P. sinuosus Herbst 为代表,目前也只有此一个种。其最主要的特征就是叶迹具多个维管束,且排列无规则;茎维管束非常长,呈盘绕状。该组目前仅发现于南美地区二叠系。生殖器官归入虫囊蕨属Scolecopteris(Zenker)Millay,建立一新种:贵州虫囊蕨。该种仅保存有聚合囊和分散的孢子囊,生殖小羽片不明。孢子囊面向外的壁较厚,但分化,自内向外可分为三部分;孢子具三缝,较大,直径55-60μm。由于该种同时拥有Millay 认为的原始特征(大的孢子)和进化特征(即分化的孢子囊面向外的壁)。很可能Millay 的观点仅仅反映了欧美植物区虫囊蕨属的演化规律。

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The technique of balancing cross-sections, an important method for studying the tectonic history of sedimentary basins, has many applications. It enables one to compile charts for petroleum exploration and development, and growth sections of ancient structures can be restored so that the structural growth history can be studied. In order to study tectonic evolution in the Zhuanghai area of the Bohai-Bay basin, we selected two seismic profiles and compiled two structural growth sections. Based on the two balanced cross-sections, the evolution can be divided into four phases: the Triassic-Middle Jurassic phase, Late Jurassic - Cretaceous phase, Palaeogene extension phase, and Late Palaeogene-to-present phase. The whole area was uplifted during the Triassic-Middle Jurassic phase because of intense extrusion stress related to the Indo-China movement. During the Late Jurassic and Early Cretaceous, intense extension occurred in east China, and the whole area rifted, leading to the deposition of a thick sedimentary sequence. In the Late Cretaceous, the area suffered uplift and compression associated with the sinistral strike slip of the Tanlu fault. In the Palaeogene, a rifting basin developed in the area. Finally, it became stable and was placed in its present position by dextral strike-slip motion. In addition, some problems associated with compiling balanced cross-sections are discussed.

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Sedimentary basins in the Yellow Sea can be grouped tectonically into the North Yellow Sea Basin (NYSB), the northern basin of the South Yellow Sea (SYSNB) and the southern basin of the South Yellow Sea (SYSSB). The NYSB is connected to Anju Basin to the east. The SYSSB extends to Subei Basin to the west. The acoustic basement of basins in the North Yellow Sea and South Yellow Sea is disparate, having different stratigraphic evolution and oil accumulation features, even though they have been under the same stress regime since the Late Triassic. The acoustic basement of the NYSB features China-Korea Platform crystalline rocks, whereas those in the SYSNB and SYSSB are of the Paleozoic Yangtze Platform sedimentary layers or metamorphic rocks. Since the Late Mesozoic terrestrial strata in the eastern of the NYSB (West Korea Bay Basin) were discovered having industrial hydrocarbon accumulation, the oil potential in the Mesozoic strata in the west depression of the basin could be promising, although the petroleum exploration in the South Yellow Sea has made no break-through yet. New deep reflection data and several drilling wells have indicated the source rock of the Mesozoic in the basins of South Yellow Sea, and the Paleozoic platform marine facies in the SYSSB and Central Rise could be the other hosts of oil or natural gas. The Mesozoic hydrocarbon could be found in the Mesozoic of the foredeep basin in the SYSNB that bears potential hydrocarbon in thick Cretaceous strata, and so does the SYSSB where the same petroleum system exists to that of oil-bearing Subei Basin.

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Based on fine structural interpretation on seismic profiles of buried-hills in Huanghua depression, structural interpretation and balanced cross-section restoration of regional seismic profiles, drawing structural maps of main seismic interfaces, residual strata distribution of different ages in the Bohai Bay region and structural survey in the western Shandong uplifted area and the intracontinental orogeny of Yanshan mountain, the paper has studied pre-tertiary structural styles and tectonic evolution of the Bohai Bay region. There mainly develop 5 types of pre-tertiary structural style that are extension structure, compression structure, strike-slip structure, negative inversion structure and sliding structure in the Bohai Bay region. Among these 5 types of structural style, extension structure develops detachment fault and its controlling fault terrain structure and fault break slop; compression structure develops reverted fold, fault propagation fold, fault bent fold, imbricate thrust structure and triangle zone; strike-slip structure develops positive flower structure, negative flower structure, en-echelon structure and brush structure; negative reversion structure develops Indosinian compression and Yanshanian extension negative reversion structure, late Yanshanian compression and Cenozoic extension negative reversion structure; sliding structure develops interlayer sliding structure and detachment structure. According to Cangdong fault of SN direction, Zhangjiakou – Penglai fault and Qihe – Guangrao fault of NWW direction, the Bohai Bay region can be divided into 6 sub-regions in which structural direction and style is different from each other. Structural maps of bottom boundary of Cenozoic and upper Paleozoic manifest that main NNE structural direction is formed from late Yanshanian to Himalayan movement and minor NWW structural direction and a string of area more than 8000m are mainly suggest that Indosinian tectonic pattern strongly influence on Yanshanian and Himalayan movement. Residual strata distribution characteristics of middle to upper Neoproterozoic in the Bohai Bay region manifest that middle- to neo- aulacogen position may be corresponding to late Mesozoic uplifted zone. Residual Paleozoic distribution characteristics of main ENN suggest that structural alteration should be resulted from late Yanshanian to Himalayan movement while which of minor NWW structures suggest that deeper structure should restrict shallower structure. Structural patterns of main EW fold direction in the Bohai Bay region and thrust structure in eastern part are formed late Triassic in studied area. Granite magma intrusion of early to middle Jurassic mainly develops Yanshan mountain zone. Late Mesozoic rifting basins of NEE direction are widely distributed in the Bohai Bay region and granite magma intrusions are mainly distributed in Tancheng – Rongcheng zone. Mesozoic structural evolution in the Bohai Bay region is related to scissor convergent from east to west between North China plate and Yangtze plate and gradually reinforcing of the west circum-pacific tectonic tract while basin and range province of late Jurassic and early Cretaceous may be mainly related to lithospheric thinning of North China craton in late Mesozoic.

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Firstly, established sequence stratigraphy of Sinian System-Middle Triassic Series framework in Sichuan basin,be divided into 21 second-level sequence stratigraphy and 105 third-level sequence stratigraphy.From many aspects,discussed sequence stratigraphy characteristic. On the foundation of structure unconformity and fission track analysis, on the ground of An county-Shuinin county regional seismic section, using the positive evolution equilibrium principle technology, comprehensivly be mapped structure evolution of Sichuan basin. It can be divided into seven stages, that is :Pre-Sinian basement stage, cratonic depression basin(Z1-S)stage, cratonic rifted basin(D-T2)stage, passive continental margin(T3x1-3)stage, foreland basin(T3x4-6)stage, depression basin (Jurassic Period-Miocene Epoch) stage, formed basin (Holocene Epoch) stage. Analysis on structure evolution history,burial history,source rocks thermal evolution history, Maoba changxing formation gas pool forming process can be classified into four stages: ancient lithological oil pool stages in Indosinian-early Yanshanian period(T-J1-2), ancient structure- lithological gas pool stages in middle Yanshanian period(J3-K1), structure- lithological gas pool setting stages in last Yanshanian period(K2), structure- lithological gas pool adjusting and transformation stages in Himalayan period(R-Q). Maoba feixianguan formation gas pool forming process can be classified into two stages: second structure gas pool stages in last Yanshanian period(K2),second structure gas pool physical adjusting and transformation stages in Himalayan period(R-Q),and summarize reservoir formation model. On the base of newest exploration achievement and petroleum geologic comprehensive research , demonstrate how structure controls hydrocarbon accumulation. Structure controlling source rocks behaves structure controlling main source rocks’sedimentary facies, medium-large pools mainly located at center or margin of hydrocarbon generation. Structure controlling palaeo-karst reservoirs ,reef and beach facies reservoirs, fault and fracture reservoirs. Structure controlling palaeo-uplift, and palaeo-uplift controlling hydrocarbon migration, active reservoirs’forming, palaeo-structure traps forming. Structure controls distribution of mudstone and gypsolith, controls preservation. Structure controls hydrocarbon conducting, structure traps forming and hydrocarbon accumulation. Whether or no, Structure controls total process of basin forming-source rocks’generation- hydrocarbon accumulation. It is direct effect results of structure movements that large traps’ conditions, conducting migration conditions, high quality preservation. source rocks’condition and reservoirs’ condition are the indirect effect results. In the last analysis, “source rock controlling theory”, “high quality reservoir mainly controlling theory”, “palaeo-uplift controlling theory” and “current structure deciding theory” are structure controlling hydrocarbon accumulation. There are high variability and complex mechanisms in Sichuan basin , but the regional hydrocarbon accumulation conditions are very well, such as abundant source rocks, matching process of hydrocarbon accumulation and many exploration areas. By means of integrated analysis, put forward hydrocarbon exploration direction and large-middle targets of China Petroleum and Chemical Corporation .Thus, more and more hydrocarbon proved reserve and output in Sichuan basin will be contributed to China energy industry in a long future time.

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The lithology of the buried hill of Triassic Budate group in Beier depression is epimetamorphic clastic rock and volcanic clastic rock stratum. Recently the favorable hydrocarbon show was discovered in buried hill of base rock, and large-duty industrial oil stream was obtained in some wells in Beier depression. Based on the information of seismos and wells, the tectonic framework, tectonic deformation times and faulted system of the Beier depression are comprehensively studied, then configuration, evolutional history, genetic type and distributed regularity of buried hill are defined. According to observing description and analysis of core sample, well logging and interpretive result of FMI, the lithological component, diagenetic type and diagenetic sequence of buried hill reservoir are confirmed, then reservoir space system of buried hill is distinguished, and vegetal feature, genetic mechanism and distributed regularity of buried hill fissure are researched, at the same time the quantitative relationship is build up between core fissures and fissures interpreted by FMI. After that fundamental supervisory action of fault is defined to the vegetal degree of fissure, and the fissure beneficial places are forecasted using fractal theory and approach. At last the beneficial areas of Budate group reservoir are forecasted by reservoir appraisal parameters optimization such as multivariate gradually regression analysis et. al. and reservoir comprehensive appraisal method such as weighing analyze and clustering procedure et. al. which can provide foundation for the next exploratory disposition. Such production and knowledge are obtained in this text as those: 1. Four structural layers and two faulting systems are developed, and four structural layers are carved up by three bed succession boundary surfaces which creates three tectonic distortional times homology. Three types of buried hill are divided, they are ancient physiognomy buried hill, epigenetic buried hill, and contemporaneous buried hill. 2. Reservoir space of Budate buried hill is mainly secondary pore space and fissure, which distributes near the unconformity and/or inside buried hill in sections. The buried hill reservoir experienced multi-type and multi-stage diagenetic reconstruction, which led to the original porosity disappeared, and multi secondary porosity was created by dissolution, superficial clastation and cataclasis et. al. in diagenetic stage, which including middle crystal pore, inter crystal pore, moldic pore, inter particle emposieu, corrosion pore space and fissure et. al. which improved distinctly reservoir capability of buried hill. 3. The inner reservoir of buried hill in Beier depression is not stratigraphic bedded construction, but is fissure developing place formed by inner fault and broken lithogenetic belt. The fissures in inner reservoir of buried hill are developed unequally with many fissure types, which mainly are high angle fissure and dictyonal fissures and its developing degree and distribution is chiefly controlled by faulting. 4. The results of reservoir comprehensive evaluate and reservoir predicting indicates that advantageous areas of reservoir of buried hill chiefly distributes in Sudeerte, Beixi and Huoduomoer, which comprehensive evaluate mainly Ⅱand Ⅲ type reservoir. The clues and results of this text have directive significance for understanding the hydrocarbon reservoir condition of buried hill in Beier depression, for studying hydrocarbon accumulated mechanism and distributed regularity, and for guiding oil and gas exploration. The results of this text also can enrich and improve nonmarine hydrocarbon accumulated theory.

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Sandstone-type uranium deposits are frequently found close to oil fields or uraniferous sandstones contain bitumen or petroleum. However, few evidence has been presented to indicate the association of uranium mineralization with petroleum oxidation. Thus, Dongsheng uranium deposit in Ordos Basin and Qianjiadian deposit in Kailu Basin are taken for examples to solve the puzzle. Integration data from sedimentary petrology, mineralogy, race elements geochemistry, isotope geochemistry and organic geochemistry, the uranium and petroleum sources, and diagenetic paragenesis of the host sandstone are analyzed, and then the genetic relationship between microbes, petroleum and uranium deposits are discussed. The observation under microscope shows that the host sandstone samples from Middle Jurassic Zhiluo Formation in the Dongsheng deposit contained different kinds of metamorphic rock fragments, which should have been derived form outcrops north to this basin. The LREE/HREE ratios of gneiss and amphibolite sampled from outcrops were close to the highest and the lowest LREE/HREE ratios of the sandstones with well-compared chondrite-normalized REE patterns, respectively. So these results consistently indicated that parent rocks of sandstones were mainly contributed from these two kinds of metamorphic rocks. There was very high Th/U ratio for granite gneiss, which was a mainly potential U resource. Hydrocarbon inclusions and adsorbed hydrocarbons are observed under fluorescence microscope in the host sandstone of Dongsheng uranium deposit, suggesting that the sandstones may have been utilized as oil migration pathways. Based on biomarker parameters, it is indicated that the inclusion oils and adsorbed hydrocarbons were marginally mature to mature, and were derived from humic-sapropel type organic matter under poor reducing freshwater to semi-saline environment. The features are similar to those of organic matter extracted from Triassic sandstone and source rock, but are different from that of cretaceous sandstone. Thus, it can be concluded that the inclusion oils and adsorbed hydrocarbons were mainly derived from Triassic lacustrine facies source rock. Observation results under Scanning Electron Microscopy and Electron Microprobe with Energy Spectrum Analysis show that, in Dongsheng area, the main uranium ore mineral is coffinite. The coffinite is intimately intergrown or coexists with pyrite and calcite, thus, the solution during mineralization stage is inferred to be alkaline. The alkaline environment is not favored for uranium to be pre-concentrated by absorption, and then be reduced abiogenetically. δ34S of pyrite and δ13C of calcite indicate that pyrite was formed by bacterial sulfate reduction (BSR) and part of the carbon of calcite has been dirived from oxidation of petroleum, respectively. Additionally, petroleum is found biodegraded. All the lines of evidence consistently indicate that petroleum was involved in uranium mineralization. Coffinite with microbe-like structures is found in the high U sandstone samples and is composed of nanoparticles, indicating the coffinite is biogenic. The conclusion are also supportted by laboratory experiment studies, which have shown that SRB are capable of utilizing U(VI) as the preferred electron acceptor for respiration and reduce U(VI) to U(IV) directly, coupled the oxidaton of organic matter and sulfate reduction. Based on the research results mentioned above, in the Dongsheng area, coffinite is likely to have formed by mixing of brine containing petroleum derived from Triassic with uranium-bearing meteoric water from outcrops north to Ordos Basin. SRB utilize hydrocarbon as carbon source, and directly reduce U(VI) resulting in precipitation of coffinite. The product of metabolism, H2S and CO2, was precipitated as pyrite and calcite during mineralization stage. Petroleum in fluid inclusions and adsorbed type in host sandstone from Lower Cretaceous Yaojia Formation in Qianjiadian uranium deposit, Kailu Basin, are derived from Jurassic Jiufotang Formation in this basin and the uranium mineral consists mainly of pitchblende. The δ34S and δ13C values of pyrite and calcite during mineralization stage indicate SRB have likely degraded petroleum, which is similar to that of Dongsheng deposit. The alkaline environment as indicated by the diagenetic mineral assemblage calcite, Fe dolomite, pyrite and pitchblende deposit suggests that U ore in the Qiangjiajiadian has a similar origin, i.e., direct reduction by SRB. However, less part of pitchblende is intergrown with kaolinite, suggesting the solution during mineralization stage is acidic. The environment is favorable for U(VI) to be adsorded on quartz or other mineral, and then reduced by H2S produced by SRB. Thus, it can be concluded that U(VI) reduction with petroleum oxidation by SRB and other microbes is an important ore-forming mechanism in petroleum-related sandstone-type uranium deposits. The finding is significant in that it provides a theoretical basis for exploration of both uranium and petroleumr.

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Tazhong-Bachu region is located in the Western Tarim basin.The early Permian magmatic rocks occur in the earth surface of Tazhong-Bachu region are mainly distributed in Kepintag,Mazhartag and Wajilitag region. There are a lot of wells, in which researchers found the early Permian magmatic rocks,in desert cover area.Most magmatic rocks are basic rocks, a few of which are ultrabasic rocks and intermediate-acid magmatic rocks.The ultrabasic rocks are are mainly occur in the Cryptoexplosive Breccia Pipes ,which is located in the volcanic complex body of Wajilitag region.The basic rocks can be divided into three rock types:The first type of the magmatic rocks in Tazhong-Bachu region is volcanic rock ,which occurs in the Lower Permian Kupukuziman Formation and Kaipaizileike Formation. Most Volcanic rocks are basalts,a few of which are volcanic breccias and pyroclastic rocks.The basalts are distributed in stratiform occurrences and interbeded the clastic rocks in Kepintag region.The attitudes of the basalts are nearly horizontal.Columnar Joints, gas pore textures and amygdaloidal structure are to develop in basalts.The second type of the magmatic rocks in Tazhong-Bachu region is diabase,which occurs in Mazhartag region.Diabase dike swarms occur in the stratums of Silurian, Devonian, Carboniferous and Lower Permian.They make from NNW direction to SSE direction, the obliquity of stratum is greater than 60°, and the dike thickness is form several cm to several meters. Diabasic texture is found in the rocks .The first type of the magmatic rocks in Tazhong-Bachu region are gabbro- pyroxenite rocks ,which occur in the Wajilitag igneous complex body. The intermediate-acid magmatic rocks, which are mainly syenites, are located in Mazhartag and Wajiltag region. But they are small in the whole Tazhong-Bachu region.There are intermediate-acid magmatic rocks,which are mainly dacite,in the northeast part of the wells in Tazhong-Bachu region.But ,it is not found in earth surface.Through systematical geochemical research of early Permian magmatic rocks,which are distributed in Kepintag,Mazhartag, Wajilitag region and the wells such as F1 well、Z1 well、Z13 well、TZ18 well、H3 well、H4 well et al., the focus on the geochronologic characteristics, the main element,trace element and REE geochemistry, the mineralogic characteristics, the Sr-Nd and Pb isotopic characteristics are put forward. The main points are: 1、A combined study of CL imaging and LA-ICP-MS U-Pb dating were carried out for zircon grains of the magmatic rocks in the Tazhong-Bachu region from the Tarim basin.The results of the systematic zircon LA-ICP-MS U-Pb dating reveal 272±6Ma to 291±10Ma for the magamatic rocks. It indicated that Early Permian is an important period of magmatic acvivity in the Tazhong-Bachu region. 2、There are a big hunch in the curves of primitive mantle-normalized trace element concentrations in the early Permian magmatic rocks from Kepintag, Mazhartag, Wajilitag region and the 14 wells. Light rare earth elements are comparatively rich and heavy rare earth elements are comparatively poor. The slope rates are same between light rare erath elements and heavy rare earth elements. It is not like the curves of the basalts in the convergent margin of plate , in which the slope rates of light rare erath elements is bigger than the alope rates of heavy rare erath elements, and the curves of heavy rare earth elements are comparatively flat. The magmatic rocks of Tazhong-Bachu region rarely have the characteristics of the basalts in the convergent margin of plate, which is that Tantalum, Niobium and Titanium are much poor, and Zirconium, Hafnium and Phosphorus are moderately poor. The magamatic rocks are mostly alkaline, which is indicated by the dots of the (Na2O+K2O)-SiO2 identification diagram. All of these indicate that the early Permian magmatic rocks were formed in an extension environment of intraplate. 3、The Thorium abundance is high and Tantalum abundance is low in most magmatic rocks from Tazhong-Bachu reguion, which is formed for crustal contamination.In the Th/Yb-Ta/Yb identification diagram,most dots are in the region, which means active continental margin, but a few dots are in the region, which means mantle source. It indicated the feeding of continental crust materials. 4、The magnesium content of the olvines from Wagilitag region is richest, and the olvines from Kepintag region is poorest in the tree region. 5、Through the the Sr-Nd and Pb isotopic study of the basalts and diabases from the F1 well core, Z1 well core, Z13 well core,TZ18 well core, and the basalts,gabbros, diabases(diabase-prophyrites) and pl-peridotites from Kepintag,Mazhartag, Wajilitag region , it indicated that all isotopic data is similar and close to enriched mantle.

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Located in the Paleozoic uplift along the southern margin of Tu-Ha basin in eastern Xinjiang, the newly discovered Hongshan Cu-Au deposit occurs in the superimposed Mesozoic volcanic basin upon the north section of later Paleozoic Dananhu-Tousuquan accretionary arc. Kalatage Cu-Au orebelt is controlled by NWW-trend faults, and includes Hongshan and Meiling Cu-Au deposits. The host rocks of Hongshan ore district are mainly rhyolitic-dacitic ignimbrites, whereas Cu-Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and granitic porphyry. Mineralization styles are dominantly veinlet-disseminated and veinlet, occasionally stockwork. The mineral association is chalcopyrite, pyrite, bornite, chalcocite and sphalerite. The hydrothermal alteration consists of silicfication, sericitization, alunitization, pyrophylitization, illitization, hydromuscovitization, and chloritization. Hongshan Cu-Au deposit, on the edge of the desert, is one of the driest areas in eastrn Tianshan. Moreover, the highest temperature has been up to 60℃, and the average rainfall receives only 34.1mm/y. The light rainfall and rapid evaporation in the vicinity of this deposit have allowed the formation of a great variety of water-soluble sulfates. Oxidization zone of this deposit lies on the upper part of primary sulfide orebodies appearing with a depth of 50-60m, which is dominant in sulfate minerals. 1. Based on the field observation, the volcanic and sub-volcanic rock composition, hydrothermal alteration, ore structure and mineralization characteristics, this paper proposed that the Hongshan Cu-Au deposit belongs to a transitional type from high-sulfide epithermal to porphyry Cu-Au deposit, which corresponds with the typical HS-epithermal deposit such as Zijinshan Au-Cu deposit in Fujian Province, SE-China. 2. The Hongshan copper-gold deposit was controlled by the tectonic, stratum, magma activity and volcanic apparatus, whereas Au mineralization is closely related to quartz porphyry, rhyolitic porphyry and fine grained pyritization in hydrothermal activity, and Cu mineralization is closely related to quartz porphyry and hydrothermal explosive breccia. 3. Oxidation zone of Hongshan Cu-Au deposit lies on the upper part of primary sulfide orebodies deposit. 23 sulfate minerals were identified in this work. The results of samples XRD and chemical analysis were furthermore confirmed through thermal, infrared spectrum and mössbauer spectrum analysis. Among those, nine minerals as Ferricopiapite, Cuprocopiapite, Rhomboclase, Parabutlerite, Krausite, Yavapaiite, Metasideronatrite Kroehnkite and Paracoquimbite were founded in China for the first time. And Paracoquimbite was secondly reported in the world (first case reported at 1938 in Chile). 4. EPMA analysis shows that Al impurity in crystal lattice is important to polytype formation of paracoquimbite and coquimbite besides stack fault. 5. Compared with Meiling Cu-Au deposit in the same Kalatage ore belt from the characteristics of δ34S of barite, lithofacies, hydrothermal alteration and homogeneous temperature, Hongshan Cu-Au deposit belongs to the same metallogenic system of HS-epithermal type as Meiling Cu-Au deposit. But Hongshan Cu-Au deposit has less extensive alteration and shallower denudation. 6. Sulfur isotope analyses show that δ34S values of pyrites vary in the range of +1.86‰~+5.69‰, with an average of 3.70‰, mostly in the range of +1.86‰~+3.20‰, and δ34Scp<δ34Spy. Therefore ore-forming fluid of porphyry comes from mantle and was contaminated by the earth’s crust. Sulfur isotope has reached balance in ore-forming process. 7. Sulfur isotope analyses show that δ34S values of sulfates vary in the range of +2.15‰~+6.73‰, with an average of +3.74‰, mostly equals as δ34S values of primary sulfides in Hongshan Cu-Au deposit. So supergene sulfates inherit sulfur of primary sulfide. δ34S values are mostly same in different sulfates. As well as pyrite and chalcopyrite, volcanic hot spring and associated native sulfur underground also provide water medium and sulfur during the formation process of sulfate. 8. According to the EPMA of sample chalcopyrite and pyrite in Hongshan Cu-Au, the value of Cu/Ni is 0.98-34.72, mostly close to the value of 5, which shows that Hongshan deposit is a typical volcanogenic magmaic hypothermal deposit. Au and Ag, Zn, Te and Bi are positive correlation, Cu and Hg, Se, Sb are positive correlation, indicates Au and Cu don’t locate in the factor of mineralization of same mineralization groups. The reasons of gold concentration in the oxidation zone are: 1). Change of redox potential (Eh) makes gold to deposit from the liquid of mineralization zone; 2). PH is one of the most factors of gold’s deposition; 3). Soluble complex and colloid of gold can be adsorbed easily. 9. The biotite and hornblende K-Ar isotopic ages from the wall rock-quartz diorite, biotite granite and monzonite granite are 231.99±3.45Ma, 237.97±2.36Ma and 296.53±6.69Ma respectively. The ore-bearing rhyolitic breccia lava contains breccia of the biotite granite which indicates the volcanism and related Cu-Au mineralization occurred later than the granite, possibly in Mesozoic. K-Ar ages of granitoids in Sanya, Baishiquan and Hongliugou area and Molybdenite Re-Os age of Baishan Mo deposit all are in Triassic. Besides late Paleozoic magmatism, igneous magmatic event of Mesozoic was widespread in eastern Tianshan. 10. The K-Ar age dating indicates that the K-Ar age of Voltaite occurred below surface 1m is 56.02±3.98Ma, K-Ar age of Ferricopiapite occurred below surface 1.5m is 8.62±1.12Ma, K-Ar age of Yavapaiite occurred below surface 14 m is 4.07±0.39Ma, and K-Ar age of Voltaite occurred below surface 10 m is 14.73±1.73Ma. So the age interval of oxidation zone of Hongshan copper-golden bed is between 60 -3.38Ma. Oxidization occurred at Caenozoic era (from 65Ma), which can be identified through comparing with different deposits oxidation zone in other countries. The coupling between global tectonic event and climatic change event which occur from Caenozoic era has some effect on epigeosphere system, which can act on the surface of bed oxidation zone similarly. It induces that the age mentioned above coincide with collision of India-Asia and multistage uplifting of Qinhai-Tibet Plateau happened subsequently. Bed oxidation zone is the effect and record of collision and uplifting of Tibet Plateau. The strong chemical weathering of surface accumulation to which was leaded by PETM event occurred Paleocene and Eocene is the reason of Voltaite sharply rises. On the contrary, Ferricopiapite formed due to the global cold weather. The predecessor did much research through biota, isotopes, susceptibility, but this paper try to use different sulfate mineral instead of climatic change. So the research of sulfate minerals not only indicates a great deal of oxidized zone feature, but also the intergrowth of sulfate minerals may be used to trace paleoenviroment and paleoclimate of oxidation zone. 11. Analysis of the information of alteration and mineralization features of four bore cores, induced activity polarization well logging and Eh-4 geophysical section, deep mineralization anomaly objects of Hongshan ore districts shows low resistance, middle and high polarization, measurements of Eh-4 consecutive conductance section show the existing of concealed porphyry ore body deeper than 450m, on the top of and around rock body there are low resistance body ranged from 100-300Ω•m, this area may be the ore-bearing part. In a word, Hongshan Cu-Au deposit deposit is a combine of upper HS-style epithermal Au deposit and deeper porphyry mineralization system. It has great potential to find large HS-style epithermal-porphyry Au-Cu deposits. This paper consists of seven chapters and twenty seven sections. The geological character of deposit is basic condition in this work. Constitute of oxidation zone, research of sulfate mineral, relation between oxidation and primary zone, K-Ar ages of potassic sulfate are key parts of thesis. Genesis of ore deposit is the further expansion of this research. Analysis of ore-controlling factors is the penetration above basic. Analysis of potential is application of exploration.

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The disequilibrium between supply and demand the east part of North China accelerated natural gas exploration in Bohai bay basin. Exploration practice showed that coal-derived gas is important resource. In searching of big to middle scaled coal derived gas field, and realize successive gas supply, the paper carried out integrated study on structural evolution of Pre-Tertiary and evaluation of reservoir forming condition of coal-derived gas. Study work of the paper was based on the following condition: available achievement in this field at present, good understanding of multiphase of tectonic movement. Study work was focused on geological evolution, source rock evaluation and dissection key factors controlling reservoir forming. Based on analysis of seismic data, drilling data, tectonic style of Pre-Tertiary was subdivided, with different tectonic style representing different tectonic process. By means of state of the art, such as analysis of balanced cross section, and erosion restoration, the paper reestablished tectonic history and analyzed basin property during different tectonic phase. Dynamic mechanism for tectonic movement and influence of tectonic evolution on tectonic style were discussed. Study made it clear that tectonic movement is intensive since Mesozoic including 2 phase of compressional movement (at the end of Indo-China movement, and Yanshan movement), 2 phase of extensional movement (middle Yanshan movement, and Himalayan movement), 2 phase of strike slip movement, as well as 2 phase of reversal movement (early Yanshan movement, and early Himalayan movement). As a result, three tectonic provinces with different remnant of strata and different tectonic style took shape. Based on afore mentioned study, the paper pointed out that evolution of Bohai bay basin experienced the following steps: basin of rift valley type (Pt2+3)-craton basin at passive continental margin (∈1-2)-craton basin at active continental margin (∈3- O)-convergent craton basin (C-T1+2)-intracontinental basin (J+K). Superposition of basins in different stage was discussed. Aimed at tectonic feature of multiple phases, the paper put forward concept model of superposition of tectonic unit, and analyzed its significance on reservoir forming. On basis of the difference among 3 tectonic movements in Mesozoic and Cenozoic, superposition of tectonic unit was classified into the following 3 categories and 6 types: continuous subsidence type (I), subsidence in Mesozoic and uplift for erosion in Cenozoic (II1), repeated subsidence and uplift in Mesozoic and subsidence in Cenozoic (II2), repeated subsidence and uplift in Mesozoic and uplift for erosion in Cenozoic (II3), uplift for erosion in Mesozoic and subsidence in Cenozoic (II4), and continuous uplift (III). Take the organic facies analysis as link, the paper established relationship between sedimentary environment and organic facies, as well as organic facies and organic matter abundance. Combined information of sedimentary environment and logging data, the paper estimated distribution of organic matter abundance. Combined with simulation of secondary hydrocarbon generation, dynamic mechanism of hydrocarbon generation, and thermal history, the paper made static and dynamic evaluation of effective source rock, i.e. Taiyuan formation and Shanxi formation. It is also pointed out that superposition of tectonic unit of type II2, type II4, and type I were the most favorable hydrocarbon generation units. Based on dissection of typical primary coal-derived gas reservoir, including reservoir forming condition and reservoir forming process, the paper pointed out key factors controlling reservoir forming for Carboniferous and Permian System: a. remnant thickness and source rock property were precondition; b. secondary hydrocarbon generation during Himalayan period was key factor; c. tectonic evolution history controlling thermal evolution of source rock was main factor that determine reservoir forming; d. inherited positive structural unit was favorable accumulation direction; e. fault activity and regional caprock determined hydrocarbon accumulation horizon. In the end, the paper established reservoir forming model for different superposition of tectonic units, and pointed out promising exploration belts with 11 of the first class, 5 of the second class and 6 of the third class.

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Shijiawan –Lijiacha area, lying on the northeastern part of the Shanbei Slope of Ordos Basin, was selected as studying area. The previous explorations proved that the 2nd segment and 6th segment of the Yanchang Formation are the most important oil-bearing formations. It is indicated that the sedimentary facies and reservoir characteristics restricted the hydrocarbon accumulation regularity. Therefore, with petrology methodologies, such as outcrop observation, core description, geophysical logging interpretation, thin section determination, scanning electron microscope, as well as rock property analysis, the reservoirs was were systematically studied and characterized. The sedimentary micro-facies, seals, reservoir-seal combines, migration pathways and entrapping modes were taken into account. The author tempted to establish a base for further studies on reservoirs and on petroleum geology, and to provide some reliably geological evidences for later prospect activities. It was found that the sediments in the 2nd and 3rd segments of the Yanchang Formation in Shijiawan –Lijiacha area were deposited in braided rivers, and most sandy-bodies were identified as channel sandbars. The 4+5th and 6th segments were principally deposited in deltaic-plain environment, consisting of corresponding sub-facies such as distributary channels, natural levee, crevasse-splay and marsh. The skeleton sandy-bodies were identified as sandy sediments of distributary channels. The sand grains in reservoir in studied area possess generally low mineralogical maturity and moderate structural maturity, and the form of pores may be classified into intergranular types and dissolved types. Most reservoirs of Yanchang Formation in Shijiawan –Lijiacha area belong to extreme low-porosity low-permeability ones (type III), and the 2nd sediments belongs to low permeability one (type II) and the 6th segment belong to super low-permeability one(type Ⅳ). The reservoirs in the 2nd segment behave more heterogeneous than those in the 6th segment. The statistic analysis results show that, for 6th and 4+5th segments, the high quality reservoir-seal combines may be found everywhere in the studied area except in the northwest and the southwest parts; and for 1st and 2nd segments, in the northeast, central and southwest parts Petroleum migration happened in the duration of the Early Cretaceous period in both lateral and vertical directions. The migration paths were mainly constructed by permeable sandy-bodies. The superimposed channel sandy-bodies consist of the principal part of the system of carriers. the vertical fractures, that may travel through the seals between reservoirs, offered the vertical paths for migrating oil. It may be synthesized that oil coming from south kitchens migrated first laterally in carriers in the 6th segment. When arrived at the studied area, oil will migration laterally or/and vertical within both the sandy-bodies and fractures, in a climbing-stair way. The results demonstrate that the oil was entrapped in traps structure-lithology and/or lithology traps. In some cases, the hydrodynamic force may help to trap oil. Accumulation of oil in the area was mainly controlled by sedimentary facies, seals, structure, and heterogeneity of reservoir in the 2nd, 4+5th and 6th segments. Especially, the oil distributions in both the 2nd and 6th segments were obviously influenced by seals in the 4+5th segment. The existence of seals in 1st segment seems important for accumulation in the 2nd segment.

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Based on outcrop, borehole, seismic and regional geological data, the sequence stratigraphy, sedimentary facies of the Triassic in the western margin of the Zhugaer basin was studied, and favorable exploration target was forecasted. The major achievements include: (1) the Triassic in the western margin of the Zhugaer basin can be divided into 1 second-order sequence and 5 third-order sequences, which are, in ascending order, TSQ1, TSQ2, TSQ3, TSQ4, and TSQ5. TSQ1 is equivolent to Baikouquan formation, TSQ2 is equivolent to lower Kelamayi formation, TSQ3 is equivolent to upper Kelamai formation, TSQ4 is equivolent to lower and middle Baijiantan formation, and TSQ5 is equivolent to upper Baijiantan formation. Each sequence is divided into transgressive and regressive system tracts. Thus the sequence correlation framework is established. (2) The factors controlling development of sequences are analyzed, and it is believed that tectonic is the major controlling factor. Model of sequence development is summarized. (3)Through study on sedimentary facies, 6 types of facies are recognized: alluvial fan, fan delta, braided river, braided delta, delta and lake. Their microfacies are also recognized. In this study, it is proposed that the upper and lower Kelamayi formation(TSQ2、 TSQ3)is deposited by braided river instead of alluvial fan. This conclusion is of important theoretical and practical significance.(4) The sedimentary facies map of each sequence is compiled, and the sedimentary facies developed in each sequence is determined. In TSQ1, the sedimentary facies developed is alluvial fan and fan delta. In TSQ2, the sedimentary facies developed is mainly alluvial fan and fan delta in the north, and braided river and braided delta in the south. In TSQ3, the sedimentary facies developed is mainly braided river and braided delta. In TSQ4, the sedimentary facies developed is mainly braided delta in the north, and meandering delta in the south. In TSQ5, the sedimentary facies developed is mainly braided river and braided delta. (5) In the framework of sequence stratigrahpy, favorable areas for concealed traps are forecasted, and different types of traps are developed in different system tracts. (6) Favorable areas for future exploration are predicted.

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In this thesis, detailed studies on the sedimentology and petrophysical properties of reservoir rocks in the Shan#2 Member of Shanxi Formation, Zizhou gas field of Ordos Basin, are carried out, based on outcrop description, core description, wireline log interpretation and analysis of petrophysical properties. In the context of stratigraphic division scheme of the Upper Paleozoic in Ordos Basin, the Shan#2 Member is further divided into three subintervals: the Shan#23, Shan#22 and Shan#21, based on the marker beds,depositional cycles, wireline log patterns. Subaqueous deltaic-front distributary channels, distributed from the south to north, is identified,which is the main reservoir sand bodies for gases of Shan#2 Member at Zizhou gas field. Quartzose and lithic-quartzose sandstones, commonly with a high volume of cement, but a low volume of matrix, are the major reservoir rocks in the studied area. All sandstones have been evolved into the late diagenetic stage (referred to as diagenetic stage B) during the burial, experiencing compaction, cementation, replacement and dissolution, in which the compaction and cementation could have reduced the porosity, while dissolution could have improved the petrophysical properties. The pore types in the reservoirs are dominated by intergranular-solutional, intergranular-intercrystal and intercrystal-solutional porosity. According to the parameters and capillary pressure curves of test samples, five types of pore texture (I-V) are differentiated, in which types II and III pore textures displayed by low threshold pressure-wide pore throat and moderate threshold pressure-moderately wide pore throat, exist widespread. Sandstone reservoirs in the studied area are characterized by exceptionally low porosity and permeability, in which the petrophysical properties of those in Shan#23 horizon are relatively better. The petrophysical property of reservoirs was influenced both by the sedimentation and diagenesis. In general, the coarse quartzose sandstones deposited in subaqueous distributary channels show the best petrophysical property, which tends to be worse as the grain size decreases and lithic amount increases. Three types of gas reservoirs in Shan#23 horizon are classified according to petrophysical properties (porosity and permeability), which could have been influenced by the initial depositional facies, diagenesis and tectonics. On the basis of the study on the geological conditions of reservoirs in the area, it is concluded that sedimetary facies, diagenesis and tectonic actions can provide an important foundation for gas pool formation, which can also control the accumulation and distribution of gas reservoirs.