A Study on Sequence Stratigraphy of Mesoproterozoic and Neoproterozoic in Southern North China Platform     

Zhou Hongrui Wang Ziqiang Cui Xinsheng Lei Zhenyu Dong Wenming 《中国地质大学学报(英文版)》1996,(1)

INTRODUCTIONThestrataofMesoprotCrozoicandNeoproterozoicaredevelopedcompletelyinthesouthpartoftheNorthetnaplatformandconsistofthreesystems,inasCendingorder,Jixiaulan,QingbaikouanandSlman.BasedonadetailedinvestigationontheolltcropandthecomprehenSiveanalysis,wediscussthecharaCterofsequencestratigraphyandthecorrelationoftheMemo--Neoproterozoicinthearea.FnThRrsor~unCrsANDPARA~unCrsMeSO--NooprotffezoicRadonalfortigraphyThesouthernpartofNorthChinaplatformherereferstotheareasincluding…  相似文献   

海南同安岭-牛腊岭火山地层划分与对比     

蔡道冠  符国祥 《地质通报》1997,(4)

将同安岭—牛腊岭火山地层划分为六罗村组、汤他大岭组、岭壳村组，总厚度达５４２９ｍ。六罗村组下部以玄武安山质火山岩为主，上部为流纹质火山碎屑岩、熔岩；汤他大岭组主要为英安岩类火山岩，岭壳村组为流纹岩类的岩石，构成２个喷发旋回。根据同位素年龄，确定火山岩的时代为早白垩世，与海南岛下白垩统鹿母湾组为同期产物，相当于我国东南沿海白垩纪火山岩。  相似文献   

一种基于二次灰关联分析的数列预测法     

刘明哲  姜若维 《物探化探计算技术》1997,19(4):357-360,373

数列预测一直是评价决策中最常见而又信于把握的问题之一。本文在总结现有预测方法的基础上，结合前铛预报思想和灰色预测理论，依据数据求同原则，提出了运用二次灰关联分析，建立组合模型的预测方法，该方法易于计算机实现，并已实际应用于油气储量预测研究中。  相似文献   

Estimation of groundwater evaporation and salt flux from Owens Lake, California, USA   总被引：3，自引：0，他引：3  

S. W. Tyler  S. Kranz  M. B. Parlange  J. Albertson  G. G. Katul  G. F. Cochran  B. A. Lyles  G. Holder 《Journal of Hydrology》1997,200(1-4):110-135

Groundwater evaporation and subsequent precipitation of soluble salts at Owens Lake in eastern California have created one of the single largest sources of airborne dust in the USA, yet the evaporation and salt flux have not been fully quantified. In this study, we compare eddy correlation, microlysimeters and solute profiling methods to determine their validity and sensitivity in playa environments. These techniques are often used to estimate evaporative losses, yet have not been critically compared at one field site to judge their relative effectiveness and accuracy. Results suggest that eddy correlation methods are the most widely applicable for the variety of conditions found on large playa lakes. Chloride profiling is shown to be highly sensitive to thermal and density-driven fluxes in the near surface and, as a result, appears to underestimate yearly groundwater evaporation. Yearly mean groundwater evaporation from the playa surface estimated from the three study areas was found to range from 88 to 104 mm year⁻¹, whereas mean evaporation from the brine-covered areas was 872 mm year⁻¹. Uncertainties on these mean rates were estimated to be ±25%, based on comparisons between eddy correlation and lysimeter estimates. On a yearly basis, evaporation accounts for approximately 47 × 10⁶ m³ of water loss from the playa surface and open-water areas of the lake. Over the playa area, as much as 7.5 × 10⁸ kg (7.5 × 10⁵ t) of salt are annually concentrated by evaporation at or near the playa surface, much of which appears to be lost during dust storms in area.  相似文献   

A bivariate meta-Gaussian density for use in hydrology   总被引：3，自引：0，他引：3  

K. S. Kelly  R. Krzysztofowicz 《Stochastic Environmental Research and Risk Assessment (SERRA)》1997,11(1):17-31

Convenient bivariate densities found in the literature are often unsuitable for modeling hydrologic variates. They either constrain the range of association between variates, or fix the form of the marginal distributions. The bivariate meta-Gaussian density is constructed by embedding the normal quantile transform of each variate into the Gaussian law. The density can represent a full range of association between variates and admits arbitrarily specified marginal distributions. Modeling and estimation can be decomposed into i) independent analyses of the marginal distributions, and ii) investigation of the dependence structure. Both statistical and judgmental estimation procedures are possible. Some comparisons to recent applications of bivariate densities in the hydrologic literature motivate and illustrate the model.  相似文献   

Organism relics or kerogens in oils as oil-source rock correlation indicator     

Suping Yao  Jingrong Zhang  Kuili Jin 《中国科学D辑(英文版)》1997,40(3):253-258

Organism relics or kerogens in oils are first obsenred by a confocal laser scanning microscope (CLSM) and a transmission electron microscope (TEM). The complexes of kerogens in oils are characterized by the presence of a great variety of microfossils or macerals. These kerogens in oils are mainly the residues of the original organic substances from which oil formed, and minor kerogens from enclosing rocks enter the oils, therefore, the components and types of the kerogens in crude oils can serve as an indirect indicator of oil-source rock correlation. This method was applied to Jurassic oils in the Junggar Basin and the Turpan-Hami Basin, and there are two types of the kerogens in oils: one containing a lot of macerals from terrestrial plants may derive from coals, and the other, characterized by a high content of microscopic algae, fungus spores and Acritarch, may originate from Permian organic matter. In addition, the reflectance of the vitrodetrinites in oils can be used as an indicator of oil-source rock correlation.  相似文献   

煤的变质程度对焦炭结构构造的影响     

康西栋  胡善亭  潘治贵  潘银苗  王凌志 《吉林大学学报(地球科学版)》1997,(3)

从宏观和微观两方面对不同变质程度煤所形成焦炭的结构、构造进行了深入研究。从气煤到肥煤阶段（Ｒｏ，ｍ：０．７７％～１．１６％），焦炭气孔壁厚度逐渐增大；进入焦煤阶段（Ｒｏ，ｍ＞１．１６％），焦炭气孔壁厚度降低。气煤、１３焦煤形成的焦炭结构以各向同性体为主，焦煤、肥煤炼出的焦炭以粒状镶嵌结构为主。由气煤和高变质程度的焦煤形成的焦炭，其气孔以微孔和大孔为主，气孔分布标准差Ｄｓ最大；肥煤炼出的焦炭，其气孔分布大小较均一；１３焦煤和低变质程度的焦煤成焦后，气孔分布状况介于上述二者之间  相似文献   

扬子板块石炭纪沉积层序及其全球性对比研究   总被引：8，自引：3，他引：8  

李儒峰  刘本培 《沉积学报》1997,15(3):23-28

通过对石炭纪扬子板块内部、扬子板块与华北板块及扬子板块与欧美板块之间的不同级别沉积层序对比研究，编制了扬子板块、华北板块和欧美板块石炭纪的海平面变化曲线。在扬子板块内部，上、下扬子区２级沉积层序可以进行对比，但下扬子区海进和海岸上超滞后于上扬子区，由于资料的限制，３级沉积层序的对比还有困难；华北板块Ｆｕｓｕｌｉｎａ－Ｆｕｓｕｌｉｎｅｌａ带内的一个３级沉积层序和Ｔｒｉｔｉｃｉｔｅｓ－Ｐｅｕｄｏｓｃｈｗａｇｅｒｉｎａ带内的四个３级沉积层序，可以和扬子板块同期的３级沉积层序对比；扬子板块和北美中大陆不仅３级沉积层序可以对比，而且在晚石炭世Ｇｚｈｅｌｉａｎ期４级沉积层序也可以进行对比，但由于它们大地构造背景的差异，导致沉积层序组成内容的不同。上述对比结果被认为是冰川型全球海平面变化所形成全球沉积记录同时性的证据。并以冰期与非冰期、联合古陆形成前后等方面对相同板块内和不同板块间沉积层序的数量和级别的异同原因进行了探讨，认为石炭纪冈瓦纳大陆冰川消长是控制全球海平面变化的主要因素，因此，沉积层序应具全球同时性和可对比性，但局部沉积条件差异也将影响沉积层序组成。  相似文献   

黑龙江省砂金指纹（化学成分）特征   总被引：5，自引：0，他引：5  

吴尚全  王春宏 《黄金地质》1997,3(3):1-7

对黑龙江省８４个砂金，７个岩金样品的化学成分进行了研究。通过Ｒ型聚类分析、探讨了不同元素之间相关性及其地质意义。通过Ｑ型聚类分析将所有样品进行分类，探讨了砂金样品与已知岩金样品之间的成因联系，并对砂金的可能原生金源的剥蚀程度进行了估计。  相似文献   

小秦岭东闯金矿区花岗岩浆活动的性质   总被引：4，自引：1，他引：4  

徐启东  钟增球 《黄金地质》1997,3(3):19-24

东闯金矿区中生开岩交活动的特征是小秦岭地区这一时期岩浆活动的缩影。从钾长花岗岩墙－文峪第一次侵入体－文峪第二次侵入体，岩石向相对基性度增高方向变化，可能暗示区域岩石圈的热－物质调整从印支期至燕山早期持续增强。  相似文献