胶州湾东北侧岩芯分析     

赵全基  刘福寿 《海洋科学》1998,22(2):68-70

胶州湾是海岸带研究及开发利用的热点之一,已做过大量工作(包含钻探工作),但深入的总结不足。1994年作者对胶州湾东北侧海底和海滩进行了详细钻探,获得了丰富资料。本文作一简要分析。钻探共4个剖面35个钻孔,其中11个孔位于陆域(图1)。大部分钻孔揭穿第四系至基岩强风化层,终孔直径110mm。1　岩性分析综观岩芯,自上至下,由新到老大体划分如下几层,见表1。杂填土　主要分布在近岸,厚约0.00～3.60m,层底标高-0.07～2.95m,主要由城市垃圾和建筑垃圾组成,堆积时间短,结构松散。淤泥　层厚0.80～3.50m,自岸向海逐渐增厚,层底标高-0.23～5.30m,灰…  相似文献   

喀斯特流域岩性与枯水径流特征值的灰色关联度分析   总被引：5，自引：2，他引：3  

焦树林  梁虹 《中国岩溶》2001,20(4):274-278

喀斯特流域枯水径流特征值的影响因素很多,如气候、流域面积、岩性、土壤、地貌等等,而能够确知的信息不多。本文视喀斯特流域为灰色系统,对流域枯水径流特征值与岩性组成之间的灰色关联度及灰色相对关联矩阵进行分析,从而揭示枯水径流特征值与流域面积和岩性之间的关联规律。   相似文献   

Influence of borehole quantity and distribution on lithology field simulation     

NAN Tian  GUO Si-jia 《地下水科学与工程》2019,(4):295-308

This paper aims to study the influence of the number and distribution of drill samples on the simulation accuracy of the lithology field. This research mainly applies the variation function method in geo-statistics, and determines important indicators such as the variation, and then the lithology field is simulated by sequence index simulation. It is shown that(1) simulation error decreases with the increase of sampling density;(2) at the scale and complexity of this study, when the sampling density reaches 40/km^2, the average error of the lithology field simulation can be less than 2.0%;(3) in the study mode of examples, the simulation results of random sampling in the whole region are the most ideal, with an average error of 5.4%. The average error of the simulation results of the centralized sampling is about 10 times that of the random sampling method;(4) known from the influence analysis of the degree of study sample unevenness influence on the imitation results, under the same sample size, the simulation error decreases with the increase of the most adjacent index. When the nearest index reaches 1, the simulation error will be less than 6%, and the error variable range is within 3%.  相似文献   

鄂尔多斯盆地西南缘岐山地区中奥陶统沉积特征及沉积环境研究   总被引：1，自引：0，他引：1       下载免费PDF全文

刘  溪任战利李文厚陈  强贾德生 《地质科学》2017,(3):931-942

本文通过野外剖面实测、样品采集、薄片鉴定等手段,收集地球化学数据及前人研究材料,对岐山地区岩性组合、沉积构造进行了研究,分析其中奥陶统沉积环境演化过程。结果表明,岐山地区在中奥陶统下马家沟组早期沉积白云岩,为局限海台地环境;下马家沟组中、晚期沉积中厚层状灰岩,为开阔海台地环境;上马家沟组沉积厚层的纹层状灰岩夹碎屑流、浊流等深水沉积建造,水体逐渐加深,并进入台地前缘斜坡沉积环境;峰峰组发育厚层的纹层状灰岩,为台地前缘斜坡环境并向深水海盆靠近。由此判断岐山地区应为南缘凹陷上,除淳化-旬邑次级凹陷以外的另一个水体更深、坡度更大的次级凹陷。  相似文献   

http://www.sciencedirect.com/science/article/pii/S167498711200151X     

Xiaoyue Gao  Luofu Liu  Zhenxue Jiang  Xiaoqing Shang  Guodong Liu 《地学前缘(英文版)》2013,4(6):779-786

The unconformity surface at the bottom of the Paleogene is one of the most important migration pathways in the Sikeshu Sag of the Junggar Basin,which consists of three layers：upper coarse clastic rock,lower weathering crust and leached zone.The upper coarse clastic rock is characterized by higher density and lower SDT and gamma-ray logging parameters,while the lower weathering crust displays opposite features.The transport coefficient of the unconformity surface is controlled by its position in respect to the basal sandstone; it is higher in the ramp region but lower in the adjacent uplifted and sag areas.The content of saturated hydrocarbons increases with the decrease of the content of nonhydrocarbons and asphaltenes.The content of benzo[c] carbazole decreases as the content of benzo[a]carbazole and [alkyl carbazole]/[alkyl ＋ benzo carbazole] increases.This suggests that the unconformity surface is an efficient medium for the transportation of hydrocarbons.  相似文献   

Possible link between weak bottom simulating reflections and gas hydrate systems in fractures and macropores of fine-grained sediments: Results from the Hikurangi Margin,New Zealand     

《Marine and Petroleum Geology》2016

Small amounts of free gas in interstitial sediment pores are known to significantly lower compressional (P-) wave velocity (Vp). This effect, combined with moderately elevated Vp from the presence of gas hydrates, is usually thought to be the cause for the often observed strong negative reflection coefficients of bottom simulating reflections (BSRs) at the base of gas hydrate stability (BGHS). At several locations however, weak BSRs have been observed, which are difficult to reconcile with a presence of gas in sediment pores. We here present a rock physics model for weak BSRs on the Hikurangi Margin east of New Zealand. Thin sections of a fine-grained mudstone sample from a submarine outcrop in the vicinity of a weak BSR show macroscopic porosity in the form of fractures and intrafossil macropores. We apply the Kuster-Toksöz theory to predict seismic velocities for a rock with water-saturated interstitial micropores and gas or hydrates in macroscopic pore space simulating fractures or compliant macropores. We match field observations of a weak BSR with a reflection coefficient of −0.016 with two end-member models; (1) rocks with gas hydrate-filled voids with a concentration of <4% of bulk sediment overlying water-filled voids, or (2) fully gas-saturated voids at a concentration of <2% beneath water-filled voids. A natural system is likely to consist of a combination of these end-members and of macroporosity filled with a mixture of water and gas or hydrate. Our results suggest weak BSRs may be caused by gas hydrate systems in fractures and macropores of fine-grained sediments with fully water-saturated interstitial pore space. Gas may be supplied into the macroscopic pore space by diffusion-driven short-range migration of methane generated within the gas hydrate stability field or, our favoured model based on additional geologic considerations, long-range advective migration from deeper sources along fractures.  相似文献   

山东黄金资源钻探井测井资料分析方法与应用     

王新娥  许东晖  孙之夫  孙宗峰  罗景美 《地球科学进展》2014,29(3):397-403

山东胶东地区为多期次岩浆活动与变质作用的产物,岩石以变质岩和岩浆岩为主。由于构造活动频繁,且处于断裂带上,岩石破碎带发育。本次科学钻探测井分析的主要任务是岩性识别与破碎带识别和划分。首先围绕岩性识别研究了多种测井交会图技术,实现了研究区钻遇的变辉长岩、片麻岩、二长花岗岩等的岩性识别,并总结了其测井响应特征。针对裂缝和破碎带分析,提出了应用主成分分析方法,并且识别结果与岩芯描述比较一致。上述岩性分析和裂缝、破碎带的测井解释结果对寻找黄铁矿石英脉起到较为重要的作用,也为综合地质信息的研究提供了可靠资料和依据。  相似文献   

地层岩性对重庆渝东南渝东北地区岩溶地下水的富集影响分析   总被引：2，自引：0，他引：2  

胡伟  吕玉香  熊开治  邓飞  刘杨 《地下水》2014,(6)

重庆市渝东南渝东北碳酸盐岩地区岩溶发育程度以灰岩类最发育,白云岩类次之,泥质灰岩类发育最弱;灰岩中的岩溶大泉、暗河数量多于白云岩类,白云岩中的岩溶大泉和暗河数量远远大于泥质、硅质岩类;而钻井成井率大小为白云岩类>灰岩类>泥质、硅质类。在岩溶找水工作中,不同地区应因地制宜,选择不同的找水方式。  相似文献