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琼东南盆地莺歌海组—黄流组海平面变化与层序年代地层 总被引：3，自引：1，他引：2
琼东南盆地晚第三纪莺歌海－黄注组为巨海相沉积,此时期内发生过多次海平面升降。本文依据对岸崖Ａ－２井有孔虫化石丰度和分异度的定量分析,崖Ａ－１井表层浮游有孔虫壳体氧,碳稳定同位素分析,、地震剖面中上超点迁移分析及对盆地古水深的恢复来研究相对海平面变化。 相似文献
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依据ＧｅｒｔａＫｅｌｅｒ和Ｇａｓｐｅｒｉ，Ｋｅｎｎｅｔｔ有关中新世印度洋和太平洋浅层水、中层水和深层水浮游有孔虫深度分层组合的划分模式，对南海琼东南盆地崖１９－１－１井晚第三纪浮游有孔虫作了定量研究，并分析了陆架海区浮游有孔虫不同深度分层组合含量的变化与古地理环境变迁的关系。崖１９－１－１井以浅层水、中层水组合为主，深层水组合不发育，反映本区温跃层不发育，不利深层水浮游有孔虫的生存。滨海区，浮游有孔虫仅为少数几个浅层水的优势种，中层水浮游有孔虫不发育；内浅海区，浅层水浮游有孔虫占绝对优势，中层水浮游有孔虫处于次要地位，所含比例相对较小；外浅海区及陆坡半深海区，浅层水和中层水浮游有孔虫均较发育，中层水浮游有孔虫百分含量相对较高。崖１９－１－１井在上新世早中期曾出现外浅海至陆坡半深海区，为古水深最大时期 相似文献
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对四川广元上寺剖面大隆组的放射虫动物群进行了详细的鉴定和丰度、分异度的统计。发现该放射虫动物群丰度和分异度均较低,以泡沫虫和内射虫为主,含少量十字多囊虫的分子;其丰度和分异度与长兴期海平面变化具有很好的耦合关系:放射虫丰度、分异度较大的层位对应于长兴早期和长兴晚期两次最大海侵事件发生的层位。相对长兴晚期而言,长兴早期放射虫的丰度和分异度较大,这与长兴早期水体相对较深有关。此外,有孔虫与放射虫丰度变化呈现很好的负相关性,这与它们不同的生活习性和水深的变化有关。分析表明:水深的变化是上寺剖面放射虫动物群演变的主要控制因素。 相似文献
5.
依据Ｇｅｒｔａ Ｋｅｌｌｅｒ和Ｇａｓｐｅｒｉ，Ｋｅｎｎｅｔｉ有关中新世印度洋和太平洋浅层水、中层水和深层水浮游有孔虫深度分层组合的划分模式，对南海琼东南盆地崖１９－１－１井晚第三纪浮游有孔虫作了定量研究，并分析了陆架海区浮游有孔虫不同深度分层组合含量的变化与古地理环境变迁的关系。崖１９－１－１井以浅层水、中层水组合为主，深层水组合不发育，反映本区温跃层不发育，不利深层水浮游有孔虫的生存。滨海区，浮 相似文献
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西藏岗巴晚白垩世有孔虫动物群与海平面变化 总被引：9，自引：0，他引：9
西藏南部岗巴地区上白垩统的有孔虫动物群十分丰富，经鉴定共有52属130种。根据岩性，该地区上白垩统可以划分出三个最基本的岩石地层单位：冷青热组、岗巴村口组及宗山组。依据其中有孔虫的形态结构、生态环境、系统演化及地史分布等特征，可以划分出五个主要的有孔虫动物群，Rotalipora动物群，Whiteinella-Helvetoglobotruncana动物群，Dicarinella-Marginotruncana动物群，Globotruncana-Globotuncanita动物群及Orbitoides-Omphalocyclus动物群。这五个有孔虫动物在晚白垩世相继绝灭，其绝灭与古水深有着十分密切的关系，主要是受海平面变化的影响。 相似文献
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鄂霍次克海南部OS03-1岩心MIS6期以来的沉积记录及其古环境意义 总被引：2，自引：1，他引：1
通过对取自鄂霍次克海南部的柱状岩心OS03-1的古海洋学研究,包括浮游有孔虫壳体AMS14C测年、底栖有孔虫壳体δ18O分析、蛋白石含量测定、有机碳含量测定、浮游有孔虫组合、冰筏碎屑含量变化、沉积物粒度分析等内容,建立鄂霍次克海OS03-1岩心年代地层学框架,分析该海区古表层海水温度、古生产力变化,并研究其古环境意义。结果表明,Neogloboquadrina pachyderma(sin.)百分含量变化曲线与Globigerina bulloides百分含量变化曲线呈很好的负相关性,与氧同位素曲线对比显示,两者均可作为该海区古温度替代性指标;浮游有孔虫绝对丰度、蛋白石含量、有机碳含量变化显示,研究区古生产力水平整体表现为间冰期较高、冰期较低;冰筏碎屑和沉积物粒度特征指示,鄂霍次克海南部间冰期陆源粗颗粒百分含量较冰期高。 相似文献
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琼东南盆地晚第三纪浮游有孔虫深度分层意义 总被引：1，自引：0，他引：1
依据Ｋｅｌｌｅ１９８５年、Ｇａｓｐｅｒｉ等１９９３年有关中新世印度洋和太平洋浅层水、中层水和深层水浮游有孔虫深度分层组合的划分模式，对南海琼东南盆地崖１３－１－４井晚第三纪浮游有孔虫作了定量研究，并分析了陆架海区浮游有孔虫不同深度分层组合含量的变化与古地理环境变迁的关系。崖１３－１－４并以浅层水、中层水组合为主，深层水组合不发育，反映该区温跃层不发育，不利于深层水浮游有孔虫的生存。滨海区，浮游有孔 相似文献
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在区域地质调查的基础上,以远安张家湾嘉陵江组剖面为重点,通过对南漳和远安交界地区下三叠统嘉陵江组剖面测制和多处化石点考察,重新厘定研究区内嘉陵江组岩性特征.认为研究区内的嘉陵江组划分为3个岩性段更为合理,产南漳-远安动物群的纹层状灰岩段位于二段顶部.通过系统化石发掘和张家湾剖面详细描述,初步查明了南漳-远安动物群的垂向分布特征:在30余米厚的纹层状灰岩段中均有海生爬行动物产出,只是丰度和分异度存在一定差异,其中7组岩层相对富集,顶部最为丰富.在此基础上,通过地层对比和所有化石点综合分析,将动物群自北东向南西划分为A~D 4个区带,依次命名为绝缘区、边缘区、相对富集区和富集区,分别对应化石从无到有、丰度逐渐变化及水深逐渐加深的过程,总体上仍处于水体循环受限的台内洼地或潟湖相环境.此次查明动物群的分布特征将为研究动物群生物与环境协同演化及其对早三叠世生物复苏的响应奠定良好的基础. 相似文献
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通过对华北地台河南鹤壁地区太原组有孔虫动物群的系统研究,共鉴定出有孔虫化石18属33种,建立了一个区域性有孔虫动物组合带：Bradyina—Palaeotextularia组合带,根据有孔虫化石的属种类型、数量,应用数理统计方法得出组合带有孔虫化石在地层中的比例变化情况,并根据化石组合带与国内其它地区的有孔虫动物群进行对比研究,认为鹤壁剖面有孔虫动物群Bradyina—Palaeotextularia组合带归于晚石炭世晚期的早期（C2^2-）,进而对研究区石炭-二叠系界线的划分进行探讨,界限应该放在第16层（泥岩）和第15层（灰岩）之间。 相似文献
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Major element, Ni, Mn and Ca electron microprobe analyses of olivine phenocrysts in one of the most primitive basalts from the FAMOUS area of the Mid-Atlantic Ridge, 527-1-1, reveal two different olivine populations, distinguished by their zoning characteristics. The often skeletal Group I olivines have zoning profiles with high forsterite, high Ni, low Mn, and low Ca cores. These profiles can be explained by low pressure crystallization from the 527-1-1 magma on cooling. The equant, often megacrystic Group II olivines also have high forsterite, low Mn cores, but the cores have low Ni compared to rims. Thus they are normally zoned with respect to Mg, Fe, and Mn but reversely zoned with respect to Ni. For example, Ni ranges from 1,700 ppm at Fo90.5 in the core to 2,100 ppm at Fo89.5 at the rim. In view of the published whole rock and mineral data of le Roex et al. (1981), the most likely explanation for these data is that the Group II olivines are xenocrysts assimilated from solidified plagioclase-pyroxene basalts through which the 527-1-1 basalt ascended. The diffusion rate of Ni and size of the xenocrystic olivines are used to calculate the residence time of the assimilated olivines in the magma. An alternative hypothesis would be a high pressure origin for the Group II olivines. This would be possible if future experiments show that with increasing pressure the partition coefficient for Ni decreases relative to the partition coefficient for Mg for a given bulk composition. Current evidence suggests this is unlikely. The data from 527-1-1 and other samples from the FAMOUS area require magmas with distinct Ni-MgO-FeO characteristics. In general, MORB from different ridge segments fall on distinct trends on plots of MgOvs. Ni as well as MgOvs. FeO. Calculation of the MgO and Ni contents of primary magmas suggests a mechanism by which such distinct trends could come about. 相似文献
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东方1-1陆上终端是国内目前天然气脱CO2规模最大的处理厂。在终端工程设计中,采用了多项新工艺、新技术。天然气处理采用先控制烃露点后增压外输流程,16亿方/年天然气脱碳装置国内领先,国内首次采用二段吸收二段再生的天然气脱碳装置,4X80m双筒型枝状段塞流捕集器设计国内首创,天然气外输解决了长输管线调峰与离心增压机正常运行的问题。终端装置2003年8月一次投产成功,工程设计荣获中国石油天然气集团公司2005年度优秀工程设计一等奖。 相似文献
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Hiroshi Nagasawa Douglas P. Blanchard Hiroshi Shimizu Akimasa Masuda 《Geochimica et cosmochimica acta》1982,46(9):1669-1673
Concentrations of rare-earth elements (REE), Sc, Fe, Co, Cr, Na and Ir in the bulk sample and mineral separates of the isotopically unique Allende inclusion, EK 1-4-1, were determined by instrumental neutron activation analysis. REE concentrations were also determined by mass-spectrometric isotope dilution for two density separates.The inclusion showed enrichment of light REE over heavy REE with a positive Yb anomaly, thus showing a tendency to resemble group II fine-grained inclusions in REE abundances, although EK 1-4-1 is a coarse-grained inclusion. High Cr concentrations also indicate group II affinity. However, high Ir (6 ppm) and Sc (105 ppm), and low FeO (1.80%), and Co (13.8 ppm) concentrations in the bulk sample and low Na concentrations in mineral separates show group I affinity.Between melilite and pyroxene fractions, the same samples in which mass-fractionated O isotope ratios were observed (Clayton and Mayeda, 1977), REE, Sc, Co and Fe showed distributions which are substantially different from those observed for “ordinary” Allende type B inclusions. These two minerals do not appear to be in equilibrium with respect to trace element distributions.The results indicate that the isotopically unique EK 1-4-1 is also unusual in its elemental abundances and distributions. 相似文献
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Guo Xuequan 《《地质学报》英文版》1994,7(3):299-309
Abstract This paper discusses geological - geophysical - geochemical models of such typical deposits as the Tieshan - type Fe-Cu deposit, the Tonglushan - type Cu - Fe deposit, the Yehuaxiang - type Cu deposit, the Jiguanzui-type Cu - Au deposit, and the Tongshankou - type Cu(Mo) deposit. The models were established based on practical data of the polymetallic deposits dominated by copper ore in southeastern Hubei. These models, which are graphically illustrated in the paper, systematically summarize the metallogenic geological conditions and the geophysical-geochemical characteristics of copper deposits in this area. The models are of practical significance for studying copper deposits, predicting mineral resources, choosing exploration methods, and searching for ore deposits based on existing ones in the study area. 相似文献
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A thermodynamic model for the Gibbs free energy of igneous pyroxenes with the general formula [Na, Ca, Fe2+, Mg]M2[Fe2+, Mg, Ti, Al, Fe3+]M1[Al, Fe3+, Si]TetSiO6 is calibrated from experimentally determined compositions of coexisting pyroxene and silicate melt. The model is based upon the general formulation, and relies upon the calibration of the “quadrilateral” subsystem, previously published by the present authors. The calibration database of pyroxene-liquid equilibria spans a broad spectrum of temperature, pressure and oxygen fugacity conditions, ranging from 1000°–1600°C, 0.001–30 kbar and iron-wüstite to air. Chemical potentials of endmember pyroxene components as well as exchange potentials between pyroxenes and coexisting liquids are defined utilizing the present authors' thermodynamic melt model. Model parameters are extracted from these relations by regression analysis. The resulting model and derivative endmember properties are internally consistent with an existing standard state thermodynamic database. The success of the model and its applicability to igneous petrogenesis are demonstrated by comparing calculated and experimentally determined liquidus compositions, temperatures and symmetry states for pyroxenes crystallizing from a variety of silicate melts, ranging in composition from tholeiites and angrites through rhyolites to potash ankaratrites. 相似文献
16.
从旺14井T1c5-1储层特征看旺隆构造T1c5-1气藏的勘探 总被引：1，自引：1，他引：0
通过对旺隆构造旺１４井Ｔ１ｃ＾５－１储层特别是岩芯冒气段的分析评价,再对比分析构造上在Ｔ１ｃ＾５－１有油气显示井的储集特征,从而得出结论：旺隆构造Ｔ１ｃ＾５－１大面积含气,呈层状民面,有孔隙即见气显示,勘探前景极好。但要形成工业气藏需要有裂缝沟通。勘探目标应着重于裂缝发育部位。 相似文献
17.
Hugo A. Loaiciga Roy B. Leipnik Paul F. Hudak Miguel A. Marino 《Mathematical Geology》1996,28(5):563-584
Starting with a stochastic differential equation with random coefficients describing steady-state flow, the effective hydraulic conductivity of 1-, 2-, and 3-dimensional aquifers is derived. The natural logarithm of hydraulic conductivity (lnK) is assumed to be heterogeneous, with a spatial trend, and isotropic. The effective conductivity relates the mean specific discharge in an aquifer to the mean hydraulic gradient, thus its importance in predicting Darcian discharge when field data represent mean or average values of conductivity or hydraulic head. Effective conductivity results are presented in exact form in terms of elementary functions after the introduction of special sets of coordinate transformations in two and three dimensions. It was determined that in one, two, and three dimensions, for the type of aquifer heterogeneity considered, the effective hydraulic conductivity depends on: (i) the angle between the gradient of the trend of lnK and the mean hydraulic gradient (which is zero in the one-dimensional situation); (2) (inversely) on the product of the magnitude of the trend gradient of lnK, b, and the correlation scale of lnK, and (3) (proportionally) on the variance of lnK,
f
2
. The productb plays a central role in the stability of the results for effective hydraulic conductivity. 相似文献
18.
东方1-1气田宏观和微观上非均质性严重,泥流冲沟发育,组分分布复杂,这些特征影响了开发效果,文章从气田沉积微相研究入手,精细描述了各类储层非均质性及其成因,借助地球物理新技术,提高地震资料的分辨率,从而进行单砂体雕刻,最终建立精细三维地质模型。通过对气田储层精细描述,认清了储层沉积微相与砂体成因类型、分布特征以及各类储层非均质性对天然气分布的控制作用;刻画了单砂体的展布、隔夹层分布以及泥流冲沟的边界;建立了实体三维储层非均质参数模型,对储层空间几何形态及物性空间变化进行精细描述。以此为依据,优化开发井的井别、井位、井轨迹,使气田开发在满足下游供气需求的同时,尽可能地平衡开采,提高气田采收率,为海上类似气田的合理开发提供参考。 相似文献
19.
晚中生代是古太平洋板块俯冲和南海北部岩浆弧发育时期,开展珠江口盆地KP1-1-1井钻遇的浅变质砂岩的近源沉积研究有助于揭示岩浆弧源区的构造特点.根据LA-ICPMS碎屑锆石分析,KP1-1-1浅变质砂岩中存在129~155 Ma、155~172 Ma和172~196 Ma三个年龄组分,这一特点与区域上构造岩浆事件一致.碎屑岩浆锆石流体活动性元素富集（如U和Th）,高场强元素亏损（如Nb、Hf和Ti）;元素组成U/Yb（0.34~3.92）、Sc/Yb（0.48~2.28）、Hf/Th（14.4~186.6）和Th/Nb（24.3~462.7）具有大陆岩浆弧特点;计算的锆石Ti温度为551~786℃,表明属于低温弧岩浆作用.碎屑岩中172~196 Ma锆石组分记录了东沙-大仑-雁荡岩浆弧向西南的进一步延伸,与侏罗纪早期古太平洋斜向俯冲到华南陆块之下有关.155~172 Ma岩浆锆石与古板块强烈俯冲有关,对应于华南165~150 Ma大规模花岗质岩浆活动.129~155 Ma时期板块俯冲减弱或俯冲带后撤,可与浙闽同时期板内强烈火山活动对比.碎屑岩中测得最年轻年龄为128.8 Ma,表明KP1-1-1钻遇浅变质砂岩形成时代晚于128 Ma,应属于白垩系,不是传统上认为的下古生界岩系. 相似文献