四川盆地西部栖霞组热液白云岩中的自生非碳酸盐矿物Word文档格式.docx

1、栖霞组；热液蚀变；萤石；氟磷灰石；重晶石；有机质强迫成熟；黏土矿物的强迫热演化Authigenic noncarbonate minerals in hydrothermal dolomite of Middle Permian Qixia Formation in the west of Sichuan Basin, ChinaHUANG Si-jing, LI Xiao-ning, HUANG Ke-ke, LAN Ye-fang, L Jie, WANG Chun-meiState Key Laboratory of Oil and Gas Reservoir Geology and E

2、xploitation, Chengdu University of Technology, Chengdu 610059, ChinaAbstract: The hydrothermal environment is an important diagenetic environment. MVT lead and zinc ore deposits and some dolomite reservoirs are related to hydrothermal environments. Based on thin section examination, scanning electro

3、n microscopy and the energy dispersion X-ray analysis, some authigenic noncarbonate minerals, including illite, fluorite, fluorapatite, quartz, barite and pyrite, and pyrobitumen are identified in the Middle Permian Qixia Formation on the west of Sichuan Basin. These minerals occur in the intercryst

4、alline/intragranular pores and dissolution pores in dolomites with different textures, especially in the dissolution pores of nonplanar-saddle dolomite. Fluid inclusion homogenization temperatures of host dolomites mainly range from 80 to 180, up to 240 or higher. The occurrence of authigenic minera

5、ls taking Ca2+ as the cation, such as fluorite, fluorapatite and also calcite in the dissolution space of dolomite, reveals that the fall of temperature after the hydrothermal dolomite precipitation causes the change of fluid nature and dissolution of dolomite. The hydrothermal alternation also lead

6、s to the formation of illite owing to forced thermal evolution of clay minerals. Pyrobitumen existing between dolomite crystals represents the forced maturation and over maturation of organic matter due to hydrothermal alternation. The hydrothermal alternation of carbonate rocks from Qixia Formation

7、 in the west of Sichuan Basin occurred during Dongwu Movement about 259 Ma B.P. （the late stage of Middle Permian）, associated with the thermal events related to the Emeishan basalt eruption with paleoheat flow up to or higher than 6080 mW/m2 and duration time of about 6 Ma. The buried depth of the

8、dolomite strata in Qixia Formation was less than 500 meters at that period, so the process of hydrothermal alteration had nothing to do with geothermal gradient function. Various authigenic minerals and pyrobitumen formed by abnormal thermal evolution of organic matter in the dolomite strata provide

9、 evidences for the hydrothermal environment diagenesis experienced by carbonates from Qixia Formation in the west of Sichuan Basin.Key words: west of Sichuan Basin; Qixia Formation; hydrothermal alternation; fluorite; fluorapatite; barite; forced maturation of organic matter; forced thermal evolutio

10、n of clay minerals下刚果盆地A区块下白垩统Albian阶沉积层序与古地理演化于水1文华国2郝立华1郝立业1程涛1郑荣才2（1.中海石油研究中心，北京 100049； 2.油气藏地质及开发工程国家重点实验室（成都理工大学），成都 610059）摘要 通过对西非被动大陆边缘下刚果盆地中的A区块沉积相和层序地层分析，确定Albian阶主要为一套具“间断-交叉”混积机理的碳酸盐岩混杂陆源砂、泥沉积，可划分出5个三级层序，经历了从混积缓坡周缘混积台地破裂混积台地深水混积陆棚深海盆地（深水扇）的沉积演化全过程，对应于威尔逊构造旋回中后裂谷拗陷阶段向大陆漂移的过渡阶段，其中发育主力储、产层

11、的SQ2-SQ3层序为型周缘混积-破裂台地沉积层序，可进一步划分为TST和HST两个体系域。解析了混积碳酸盐岩层序地层与沉积充填响应特征，建立了研究区混积碳酸盐岩“滑脱-盐拱-转换”多因素联控的沉积演化模式，提出SQ3层序时期的盐拱构造顶部呈帚状分布和垂向偏转加积发育的破裂混积台缘浅滩为最有利的储集微相类型；以TST和HST体系域作为编图单元，编制了SQ2和SQ3层序各体系域的岩相古地理图并探讨了有利储集相带展布规律，认为A区块Albian阶SQ2-HST、SQ3-TST和SQ3-HST三个体系域中预测出的叠置台缘浅滩，应成为今后的勘探重点。关键词 沉积-层序；混积碳酸盐岩；浅滩；沉积演化模式

12、；层序-岩相古地理；Albian阶；下刚果盆地Sedimentary sequence and paleogeographic evolution of Albian Stage, Lower Cretaceous in Block A of Lower Congo BasinYU Shui1, WEN Hua-guo2, HAO Li-hua1, HAO Li-ye1,CHENG Tao1, ZHENG Rong-cai21.Petroleum Research Center of CNOOC, Beijing 100049, China；2.State Key Laboratory of

13、Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu 610059, China Lower Congo Basin is located on the passive continental margin of West Africa. This paper studies the sedimentary facies and sequence stratigraphy of Block A, ascertains that Albian is a set of ca

14、rbonate rocks mixed with terrigenous sand and mud forming in a mixed mechanism of “intermittence-cross” diamictic process. Albian can be divided into five third-order sequences in the area. The whole sedimentary and evolutionary process of the strata has undergone the sedimentary rampperipheral diam

15、ictic platformfractured diamictic platformdeep-water diamictic continental shelfdeep sea basin （deep-water fan）, corresponding to the transformation phase of the Wilson structural cycle from back-arc rift depression to continental drift. SQ2 and SQ3 sequences, the main reservoirs, are Type II sedime

16、ntary sequences of peripheral diamictic-fractured platform and each sequence can be further divided into TST and HST systems tracts. The response characteristics of sedimentary sequences and sedimentary filling of mixed siliciclastic-carbonate rock are analyzed. The sedimentary evolution model of th

17、e gang control of multiple factors including “slippage, salt arch and conversion” is established. Besides, at the SQ3 sequence stage, the fractured and diamictic platform edge shoal with a broom-like distribution and the development of vertical accretion on the top of the salt arch structure will be

18、 the most favorable microfacies in the area. By taking TST and HST systems tracts as the two mapping units, the authors draw a lithofacies paleographic map of each system tracts, discuss the distribution of the favorable reservoir facies, and then make a prediction about Albian in Block A. Finally t

19、he authors think that the superimposed platform edge shoal facies in the SQ2-HST, SQ3-TST and SQ3-HST system tracts should be the key areas in the future exploration. sedimentary sequence; mixed siliciclastic-carbonate rock; shoal; sedimentary evolution model; sequence-lithofacies paleogeography; Al

20、bian; Lower Congo Basin黑龙江金厂金矿花岗斑岩锆石地球化学、U-Pb年代学及地质意义钱烨1孙丰月1李碧乐1陈静2第五春荣3（1.吉林大学 地球科学学院，长春 130061; 2.青海省地质矿产研究所，西宁 810012；3.西北大学 大陆动力学国家重点实验室，西安 710069）摘要 为确定与金厂金矿成矿有关的岩浆类型、活动时限和构造背景，采用LA-ICP-MS技术对研究区花岗斑岩开展了锆石U-Pb年龄及原位微区微量元素测定。结果表明：锆石环带发育，wTh/wU值0.4，具有岩浆锆石特征；锆石年龄分布于220 Ma和103123 Ma 2个区间，代表了2期岩浆事件；对2种

21、锆石分别命名为捕获岩浆锆石和新生岩浆锆石；锆石的地球化学和年龄信息显示捕获岩浆锆石的原岩为早三叠世花岗岩；锆石微量元素信息暗示花岗斑岩是早三叠世花岗岩高度熔融结晶分异、侵位于浅部氧化环境而形成，这一过程导致新生岩浆锆石负Eu异常程度降低。新生锆石加权平均年龄为（113.53.8） Ma，与成矿年龄一致，据此认为早白垩世的岩浆事件是金厂金矿成矿事件的直接原因，成矿背景为太平洋板块俯冲后的岩石圈伸展。关键词 锆石地球化学；锆石U-Pb年代学；岩浆锆石；地质意义；金厂金矿Geochemistry and U-Pb geochrony of zircon from granite porphyry o

22、f Jinchang gold deposit in Heilongjiang, China and its geological significanceQIAN Ye1, SUN Feng-yue1, LI Bi-le1, CHEN Jin2, DIWU Chun-rong31.College of Earth Sciences, Jilin University, Changchun 130061, China;2.Institute of Geology and Mineral Resources of Qinghai Province, Xining 810012, China;3.

23、State Key Laboratory of Continental Dynamics, Northwest University，Xian 710069, China The Jinchang gold deposit, located in the east segment of the Central Asian orogenic belt, is a large hydrothermal deposit associated with the Mesozoic magmatic activities. In order to determine the type, age and t

24、ectonic setting of the metallogenic magmatic rock, the authors measure the U-Pb dating and in situ trace elements of the zircons from granitic porphyry by cathodoluminescence （CL） images and LA-ICP-MS. All zircon grains have fine oscillatory zonings in CL images, and the ratio of Th/U is 0.4, indica

25、ting their magmatic origin. Zircon U-Pb dating is 220 Ma and 103123 Ma, representing the two-phase magmatic events. The zircon with age of 220 Ma belongs to the captured magmatic zircon. Correspondingly, zircons with ages of 103123 Ma are derived from the new magma. Geochemistry and U-Pb dating of t

26、he zircons suggest that the captured zircon was derived from the Early Triassic granite porphyry. The trace elements of the zircons indicate that the granite porphyry originated from the highly melting and crystallization differentiation and the emplacing in the oxidizing environment in the shallow

27、crust of the Early Triassic granite. The values of negative Eu anomalies in zircons from the new magma decreased in the oxidizing environment. The weighted average U-Pb age （113.53.8 Ma） of zircons from new magma is identical with the metallogenic age. Therefore, the Early Cretaceous magmatic event

28、directly resulted in the gold mineralization in the Jinchang deposit. The mineralization occurred in lithospheric extensional setting related to the subduction of the Pacific Plate. zircon geochemistry; zircon U-Pb geochronology; magmatic zircon; geological significance; Jinchang gold deposit赣西萍乐凹陷带

29、卡林型金矿的构造控矿特征杨斌1董国臣2莫宣学2曾书明3（1.成都地质矿产研究所，成都 610083；2.中国地质大学 地球科学与资源学院，北京 100083； 3.江西地勘局赣西地质调查大队，南昌 330201）摘要 探寻赣西萍乐凹陷带卡林型金矿的成矿流体来源和主要控矿因素。通过对区内2个典型的卡林型金矿点（吴村和大石芴）的野外地质调查以及成矿期包裹体H、O同位素研究，表明2个矿区的成矿流体主要组成自西向东表现出了从岩浆水到大气降水过渡的特征，而成矿热液的来源是岩浆水。通过研究赣西地区的区域构造背景、区内卡林型金矿的含矿地层、控矿断裂和矿体的产状以及岩石渗滤性与构造的关系，表明构造是区内卡林型

30、金矿的主要控矿因素，构造控矿的主要表现形式为褶皱与翼部层间滑动的组合控矿，金矿体以层状、似层状赋存在层间滑动面中。关键词 萍乐凹陷带；卡林型金矿；成矿流体来源；构造控矿；赣西Tectonic and ore-controlling characteristics of the Carlin gold deposits in the Pingle depression of Jiangxi, ChinaYANG Bin 1, DONG Guo-chen2, MO Xuan-xue2, ZENG Shu-ming31.Chengdu Institute of Geology and Mineral Resources, Chengdu 610083, China;2.China University of Geosciences, Beijing 100083, China;3.Ganxi Geological Survey of Jiangxi Bureau of Geology and Mineral Exploration