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71.
山东济阳坳陷始新统-渐新统天文地层界线年龄分析 总被引:2,自引:2,他引:0
YAO Yi-min ) XU Dao-yi ) HAN Yan-ben ) YIN Zhi-qiang ) ZHANG Hai-feng ) ) Geological Scientific Research Institute of Shengli Oilfield Company SINOPEC Dongying ) Institute of Geology China Earthquake Administration Beijing ) National Astronomical Observatories Chinese Academy of Sciences Beijing 《地层学杂志》2007,(Z2)
山东济阳坳陷沙河街组上部天文地层研究是以牛38井沙三段中亚段顶界年龄34.892Ma作为标定,分析和计算出沙二段下亚段底年龄为33.799Ma、沙段二段上亚段底为33.338Ma、沙一段底为32.940Ma和东营组底为31.829Ma。从天文地层界线年龄分析,沙三段-沙二段界线的年龄大致可对比为"国际地层表(2004)"始新统-渐新统界线年龄33.90Ma,而沙二段下亚段-上亚段界线年龄比国际始新统-渐新统界线的滞后大约600ka。在"中国区域地层表"始新统-渐新统界线年龄(32Ma)和"国际地层表"的始新统-渐新统界线年龄(33.9Ma)之差的1.9Myr,大致相当于本区计算的沙一、二段的持续时间。SP数据的小波分析表明,在沙二段-沙三上亚段界线附近,即约33.8Ma之后,约405ka周期开始变得不明显、不规则,幅度亦下降,剧烈突变发生时间在33.4Ma左右。上述界线对应偏心率周期的理论值突变的时间。因此推论始新世-渐新世转折期是偏心率多个理论周期重迭而导致的一个特殊的时期,也是本区沙二段下亚段这段地层形成不整合面的时间,大约在33.8—33.4Ma期间。 相似文献
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74.
新晃贡溪超大型重晶石矿床的岩石学特征与沉积成岩作用 总被引:9,自引:0,他引:9
本文阐述了新晃贡溪矿床沉积型重晶石岩的组构特征和5类重晶石岩,进而讨论了重晶石岩的组构特征与沉积成岩作用的成生联系。 相似文献
75.
DAVID LEE DUEWER 《地理学报(英文版)》1990,(4)
The Free-Wilson paradigm is an established and powerful tool for quantitatively relating activity withchemical structure.Current implementations of the paradigm,however,are flawed both conceptually andin execution.As part of an attempt to more fully realize the promise of the paradigm,it was necessaryto examine these limitations in detail.This report introduces a robust,theory-founded Free-Wilson implementation:stepwise principalcomponents regression analysis(SPCRA).SPCRA is computationally superior to previousimplementations but does not in itself correct their conceptual flaws.The development of SPCRA did,however,facilitate derivation of a simple and chemically significantinterpretation of the Free-Wilson structure-activity model.A number of statistical aspects of this modelcommonly misused in previous applications are discussed at length.These discussions provide criticalbackground for the development of an alternative implementation of the Free-Wilson paradigm. 相似文献
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77.
Arps递减开发模型 总被引:22,自引:8,他引:14
本文在Arps递减产能预测模型的基础上提出了Arps递减开发模型,提出了开发速度,采出程度等开发指标的数学关系式,分析了参数Arps递减开发模型的影响,提出了开发初期Arps递减开发模型的确定方法,便于开发初期决策,制作了Arps递减开发模型的logVd-logRp图版,logVd-log(Dt)图版,logRp-log(Dt)图版,提出了开发中晚期Arps递减开发模型的判断方法,三点抛物线法和三 相似文献
78.
LIU Hanlong DAI Huichao Susumu IAI
Professor Geotechnical Engineering Research Institute Hohai University Nanjing China.
Senior Engineer China Yangtze Three Gorges Project Development Corporation Yichang China.
Doctor Port Harbour Research Institute Ministry of Transport Nagase Japan. 《中国海洋工程》1999,(1)
—Effective stress analysis is performed to evaluate the residual displacement of a caissonquaywall during 1994 Hokkaido-Toho-Oki Earthquake and 1993 Kushiro-Oki Earthquake.Theconstitutive model used in this study is a multiple shear mechanism type defined in strain space and cantake into account the effect of rotation of principal stress axis.The earthquake accelerations recorded atthe outcropping rock during the earthquake are used as input bedrock motion.The results of finite ele-ment analysis are in good agreement with the observed behaviour of the quaywall.The analysis also indi-cates that liquefaction and high excess pore water pressure have a significant effect on the deformation ofthe caisson.Soil improvement is speculated as the most reliable measures against liquefaction.The influ-ence of soil improvement and the reasonable improved area are discussed in the paper. 相似文献
79.
DING Keqin DUAN Menglan FU Pinsheng LIU Chuntu
Ph. D. Associate Professor Research Department Center of Boiler Pressure Vessel Inspection Research Beijing P. R. China
Ph. D. Research Professor CCS Research Development Center China Classification Society Beijing P. R. China
Lecturer Yumen Petroleum School of Technique Technology Yumen P. R. China Research Professor 《中国海洋工程》1999,(4)
A simple probabilistic model for predicting crack growth behavior under random loading is pre-sented.In the model,the parameters c and m in the Paris-Erdogan Equation are taken as random variables,and their stochastic characteristic values are obtained through fatigue crack propagation tests on an offshorestructural steel under constant amplitude loading.Furthermore,by using the Monte Carlo simulation tech-nique,the fatigue crack propagation life to reach a given crack length is predicted.The tests are conducted toverify the applicability of the theoretical prediction of the fatigue crack propagation. 相似文献
80.
ZHANG DaJiang WANG PeiRong MAO ZhiChao & XU GuanJun Research Institute of Petroleum Exploration & Development PetroChina Beijing China Key Laboratory of Petroleum Geochemistry CNPC Geochemistry Department Yangtze University Jingzhou 《中国科学:地球科学(英文版)》2010,(4)
Twenty-five monoterpanes from six types of essential oils and hydrogenated turpentine oil have been identified and their stable carbon isotope composition determined.Monoterpanes in essential oils sourced from terrestrial higher plants display a δ13C value in the range of-34‰-26‰,and mostly between-29‰ and-27‰.The δ13C value of any single monoterpane is very consistent in different essential oils.Acyclic monoterpanes show closer isotope composition between-28.6‰ and-26.2‰,with an average value of-27.7‰.In contrast,the isotope composition of cyclic monoterpanes is more scattered with an average value of-28.6‰.Isotopic fractionation with 13C enrichment has been observed during both artificial and geological hydrogenation of monoterpenoids to monoterpanes,and this is more obvious for the acyclic monoterpenoids.In addition to higher plants,acyclic monoterpane 2,6-dimethylheptane in crude oil can also be originated from other organic inputs. 相似文献