松辽盆地科学钻探工程松科二井东孔上白垩统地球物理测井科学成果   总被引：2，自引：0，他引：2  

邹长春  张小环  赵金环  彭诚  张淑霞  李宁  肖亮  牛一雄  丁娱娇  秦宇星  林峰 《地球学报》2018,39(6):679-690

松辽盆地科学钻探工程是围绕地球深部资源、古环境与古气候等一系列重要地球科学问题而实施的重大科学工程。作为该工程的主体钻孔, 松科二井东孔设计为松辽盆地最深钻孔, 设计深度6 400.0 m, 计划穿透白垩系地层、钻至盆地基底。由于上白垩统井段取心量非常少, 因此地球物理测井的作用尤为重要。该孔正式开钻后, 采用先进的成像测井设备对一开和二开钻井井段(上白垩统井段)先后实施4次裸眼井综合测井和套管井测井作业, 并系统地开展测井综合评价, 取得以下科学成果: (1)原位获取了常规测井、特殊测井和固井质量检查测井资料共20种, 资料丰富、质量优良, 建立了上白垩统连续的岩石物理参数标准剖面; (2)完成了上白垩统地层划分、岩性识别、沉积和构造精细解释; (3)识别出泉头组油气储层、嫩江组和青山口组烃源岩层、嫩江组高放射性异常层, 以及上白垩统地热开发潜力层; (4)探索了青山口组古气候分析的有利测井指标; (5)及时提供准确的井径、钻孔轨迹和固井质量等关键钻探工程信息。研究成果对于松辽盆地地球物理勘探科学“标尺”建立、古环境与古气候研究、钻探工程施工起到至关重要的作用, 为整个钻探工程科学目标的实现奠定良好基础。  相似文献   

自升式钻井平台中高压管道应力分析     

徐红梅  韩华伟  杜之富 《海洋工程》2013,31(5):112-116

高压泥浆系统是自升式钻井平台中的重要系统,对维持生产作业、保证平台的安全具有极为重要的意义。作为一个高性能,高应力系统,对高压泥浆系统进行应力分析以便对管线系统的布置、支吊架位置和结构进行评估是很有必要的。鉴于此,从分析理论、参考标准、分析工具和校核工况组合等多个方面进行探讨,计算该高压泥浆系统的一次应力和二次应力,法兰的强度以及模态分析,得到合理的管路布置,探索出自升式钻井平台中高压泥浆系统应力分析的可行方法。  相似文献   

苏鲁榴辉岩在俯冲峰期-折返早期的递进塑性变形过程及对超高压变质岩石折返动力学的启示   总被引：1，自引：1，他引：0  

梁凤华  许志琴  陈方远 《岩石学报》2009,25(7):1587-1602

榴辉岩的变形特征严重影响俯冲板片的流变学行为,而石榴石的变形机制又直接制约着榴辉岩的变形属性。本文在结合前人研究的基础上,通过对中国大陆科学钻探（CCSD）主孔榴辉岩中石榴子石的典型变形特征的详细对比和分析,进一步证明了榴辉岩在俯冲峰期条件下可以发生强烈的塑性变形。且俯冲峰期-折返早期经历了从以恢复作用主导的位错蠕变,到动态重结晶、扩散蠕变,再到静态重结晶和矿物生长的连续递进变形过程。其中,从动态重结晶到高温静态重结晶的转换,结合短时增温、局部熔融等证据,共同证明了在苏鲁超高压变质岩石折返过程中存在一个短暂的低应力“热”区间,在此前后,折返机制和驱动力发生了转变,由浮力作用下的快速折返转为以挤压透入性剪应力作用下的缓慢抬升阶段。  相似文献   

The progressive intensification of northern hemisphere glaciation as seen from the North Pacific   总被引：4，自引：0，他引：4  

M. A. Maslin  G. H. Haug  M. Sarnthein  R. Tiedemann 《International Journal of Earth Sciences》1996,85(3):452-465

Ocean Drilling Project (ODP) site 882 (50°22′N, 167°36′E) provides the first high-resolution GRAPE density, magnetic susceptibility, carbonate, opal and foraminifera (planktonic and benthic) stable isotopes records between 3.2 and 2.4 Ma in the Northwest Pacific. We observed a dramatic increase in ice rafting debris at site 882 at 2.75 Ma, which is coeval with that found in the Norwegian Sea, suggesting that the Eurasian Arctic and Northeast Asia were significantly glaciated from 2.75 Ma onwards. Prior to 2.75 Ma planktonic foraminifera δ¹⁸O records indicate a warming or freshening trend of 4°C or 2‰ over 80 ka. If this is interpreted as a warm pre-glacial Pliocene North Pacific, it may have provided the additional moisture required to initially build up the northern hemisphere continental ice sheet. The dramatic drop in sea surface temperatures (SST>7.5°C) at 2.75 Ma ended this suggested period of enhanced SST and thus the proposed moisture pump. Moreover, at 2.79 and 2.73 Ma opal mass accumulation rates (MAR) decrease in two steps by five fold and is accompanied by a more gradual long-term decrease in CaCO₃ MARs. Evidence from the Southern Ocean (ODP site 704) indicates that just prior to 2.6 Ma there is a massive increase in opal MARs, the opposite to what is found in the North Pacific. This indicates that the intensification of northern hemisphere glaciation was accompanied by a major reorganisation of global oceanic chemical budget, possibly caused by changes in deep ocean circulation. The initiation of northern hemisphere glaciation occurred in the late Miocene with a significant build up of ice on southern Greenland. However, the progressive intensification did not occur until 3.5–3 Ma when the Greenland ice sheet expanded to include northern Greenland. Following this stage we suggest that the Eurasian Arctic and Northeast Asia glaciated at 2.75 Ma, approximately 100 ka before the glaciation of Alaska (2.65 Ma) and 200 ka before the glaciation of the North East American continent (2.54 Ma).  相似文献   

Fluid infiltration associated with seismic faulting: Examining chemical and mineralogical compositions of fault rocks from the active Chelungpu fault   总被引：3，自引：0，他引：3  

Wei-min Donald Chen  Hidemi Tanaka  Hui-jen Huang  Chung-bin Lu  Chy-yu Lee  Chien-ying Wang 《Tectonophysics》2007,443(3-4):243

In order to understand the fault zone architecture and mechanisms that caused the Chi-Chi earthquake, the Chelungpu drilling project was conducted during April 2000 through a collaborative project between Japan and Taiwan. In this study, chemical and mineralogical variations within the overall Chelungpu fault zone, including variations between less damaged host rocks, damaged zones, and fault cores caused by the Chi-Chi earthquake were examined. Slopes of TiO₂ immobile isocons were consistently > 1 for analyses comparing host rocks with rocks from damaged zones or with gouges from fault cores, indicating that volume loss occurred in damaged zones and the fault cores. These results strongly imply that pervasive fluid infiltration occurred within the fault zone. Volume loss within the damaged zone and fault core is interpreted to result from a two-stage process involving: (i) coseismic mechanical wearing and/or dissolution in the fault core, and (ii) fluid infiltration within the fault zone during postseismic and interseismic periods along cracks caused by seismic failure. Semi-quantitative XRD analysis indicates that the kaolinite content consistently increases from the less damaged host rocks to the damaged zone and gouges in each fault core. Mineralogic changes indicate that pervasive acidic fluid infiltration occurred within the fault zones and reacted with the feldspars or muscovite to form kaolinite. Enrichment of kaolinite and illite found in the fault zones of southern drilling site could play some role on the slipping behavior of the southern part of the Chelungpu fault. Greater volume loss in the fault core may have resulted from moderate permeability, combined with the very fine grain nature of pulverized material in the fault core, which enhanced chemical reactions including transformation of feldspars and muscovite to clay minerals. The study results indicate that pervasive fluid infiltration occurred and changed the mineralogical and chemical architecture of fault zones caused by the cyclic earthquakes.  相似文献   

中国大陆科学钻探工程主孔石榴石单辉橄榄岩的岩石化学研究     

李天福  杨经绥 《岩石学报》2007,23(12):3116-3136

中国大陆科学钻探工程主孔石榴石橄榄岩产出于603.20～683.53m之间,主要为石榴石单辉橄榄岩,内部还见有巨晶状角闪石岩(曾经是岩脉)和榴辉岩与橄榄岩之间厘米级的方辉辉石岩.石榴石橄榄岩多数含有钛斜硅镁石.从其内部所夹的榴辉岩条带可知,橄榄岩发生过褶皱等构造变形作用.其围岩和内部夹层榴辉岩中的锆石中舍柯石英的事实可能表明岩体经历过超高压变质作用.石榴石橄榄岩的主要造岩矿物橄榄石的Fo端员低(0.82～0.86)、全岩岩石化学的低Mg#值(77.26～85.07)和高易熔元素以及低于典型阿尔卑斯型橄榄岩的(Mg Ni)/(Fe Mn)比值,意味着该石榴石橄榄岩体的原岩为岩浆固结成因.石榴石橄榄岩的稀土元素总量低,配分型式有LREE富集型((La/Lu)N比值为9～16.6)、LREE适度富集型((La/Lu)N比值为1.47～8.22)和LREE亏损型或平坦型((La/Lu)N比值为0.62、1.19～1.92)三种,并构成从亏损或平坦型到富集型的韵律,反映了结晶分异的特点.微量元素蛛网图上,石榴单辉橄榄岩微量元素的丰度总体上低于N-MOBB的丰度.Cu、Ni和MgO的判别图表明,石榴石橄榄岩的原岩岩浆的固结成岩时期主要为镁铁质矿物的分离结晶作用而硫化物不是重要的矿物相.Ti和P的剧烈变化表明了有磁铁矿和磷灰石的堆积作用.微量元素判别图表明岩体受到了明显的地壳物质混染作用.铂族元素丰度总量低,其丰度分布型式图表明原岩岩浆的部分熔融程度高,而且元素的判别图表明岩浆具有S不饱和特点.硫化物残留在地幔中而使得岩浆中PGE相对Cu、Ni亏损,在Ni-PGE-Cu图上呈总体上的凹形分布.同属PPGE的Pt比Pd所显示的更高的相容性也表明了岩浆中S的不饱和特点.而Ir的负异常可能说明原始岩浆在侵入前的分离结晶作用其间发生了Ir的结晶析出,或者是在地幔部分熔融时Ir残留在地幔残留体中.因此,主孔石榴石橄榄岩的原始岩浆是上地幔适当部分熔融程度的产物((Pd/Ir)N≥1),可能在源区有硫化物的残余而造成了PGE相对Cu、Ni亏损而在Ni-PGE-Cu图上呈总体上的凹形分布.后S不饱和的岩浆经历分离结晶作用而造成了Pt相时于Pd亏损的特点.  相似文献   

Nd、Sr同位素组成对中国大陆科学钻探工程主孔0～2000米片麻岩原岩成因的制约     

薛怀民  刘福来 《岩石学报》2007,23(12):3231-3238

中国大陆科学钻探工程主孔0～2000岩芯段的片麻岩包括二长花岗质片麻岩和斜长片麻岩两类,其中的Sr同位素组成与元素Rb的丰度关系显示原岩侵位后发生过强烈的Rb加入事件,说明Rb-Sr同位素体系在超高压变质和随后的退变质作用过程中受到了明显的扰动.相反,Sm-Nd同位素体系尚保持着封闭状态,可有效地示踪原岩的成因.二长花岗片麻岩的εNd(t)值较低,变化范围也不大(-8.2～-13.0),它们的Nd同位素模式年龄(TDM)主要介于2.25到2.54 Ga之间,远大于其原岩的实际侵位年龄,指示其原岩可能是由古元古代的地壳物质在新元古代部分熔融形成的.而斜长片麻岩的εNd(t)值变化范围广,从 1.3到-9.4.其中采自大套斜长片麻岩段的样品其εNd(t)值从-3.0到-9.4,它们的Nd同位素模式年龄介于2.1～2.4 Ga,与二长花岗片麻岩的TDM值类似,该类岩石的地球化学特征总体类似于扬子地台北缘新元古代双峰式火山岩的酸性端元,指示它们的原岩可能是在新元古代由地幔来源的玄武岩浆上升到地壳层位,引起成分不均一的古元古代地壳物质发生部分熔融形成的,其中可能混入了少量地幔来源的物质.而采自变镁铁质岩“夹层“中的斜长片麻岩显示出接近球粒陨石的Nd同位素特征(εNd(t)= 1.3～-2.6),类似或略低于邻近的榴辉岩和斜长角闪岩围岩的Nd同位素组成及大别山-苏鲁造山带内大多数榴辉岩的Nd同位素组成,指示它们与这些变镁铁质岩之间可能有成因联系.它们的Nd同位素模式年龄(TDM=1.28-1.60 Ga)虽然早于其原岩的侵位年龄,但明显小于花岗片麻岩及大套斜长片麻岩的TDM值.我们倾向于认为这些“薄层“状的斜长片麻岩的原岩是由玄武岩浆派生的,伴有一定程度的地壳混染.  相似文献   

A Study on the Classification and Well-Logging Identification of Eclogite in the Main Hole of Chinese Continental Scientific Drilling Project     

景建恩  魏文博金胜  叶高峰邓明 《中国地质大学学报(英文版)》2007,18(4):357-365

Eclogite, one of the important lithologies in the main hole of the Chinese Continental Scientific Drilling (CCSD) Project, exists above the depth of 3 245 m and has distinctive responses of gamma-ray, compensating density and neutron well-logging, and so on. In this study, according to the diversities of minerals and chemical components and well-logging responses, eclogites are classified from three aspects of origin, content of oxygen, and sub-mineral. We studied the logging identification method for eclogite sub-classes based on multi-element statistics and reconstructed 11 kinds of eclogite. As a result, eclogites can be divided into 6 types using well logs. In the light of this recognition, the eclogite in the main hole is divided into 20 sections, and the distribution characters of all sub-classes of eclogite are analyzed, which will provide important data for geological research of CCSD.  相似文献   

云南泸西县云鹏水电站坝基基础工程处理     

马云 《云南地质》2007,26(2):249-252

大坝基础帷幕灌浆工程中采用新技术、新工艺，使工程质量大幅提高，也使这些新技也能在实践中得到发展和完善，为工程良好的质量和效益打下了坚实的基础。  相似文献   

Risk-based environmental decision-making using fuzzy analytic hierarchy process (F-AHP)   总被引：1，自引：4，他引：1  

Solomon Tesfamariam  Rehan Sadiq 《Stochastic Environmental Research and Risk Assessment (SERRA)》2006,21(1):35-50

Environmental risk management is an integral part of risk analyses. The selection of different mitigating or preventive alternatives often involve competing and conflicting criteria, which requires sophisticated multi-criteria decision-making (MCDM) methods. Analytic hierarchy process (AHP) is one of the most commonly used MCDM methods, which integrates subjective and personal preferences in performing analyses. AHP works on a premise that decision-making of complex problems can be handled by structuring the complex problem into a simple and comprehensible hierarchical structure. However, AHP involves human subjectivity, which introduces vagueness type uncertainty and necessitates the use of decision-making under uncertainty. In this paper, vagueness type uncertainty is considered using fuzzy-based techniques. The traditional AHP is modified to fuzzy AHP using fuzzy arithmetic operations. The concept of risk attitude and associated confidence of a decision maker on the estimates of pairwise comparisons are also discussed. The methodology of the proposed technique is built on a hypothetical example and its efficacy is demonstrated through an application dealing with the selection of drilling fluid/mud for offshore oil and gas operations.  相似文献