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1.
为了探测渭河新生代盆地的基底组成和结构构造,调查渭河盆地主要地层厚度、埋深和构造特征,在渭河盆地开展二维地震勘探测量,在全面收集渭河盆地以往物探和钻孔资料的基础上,通过实测地震剖面,划分渭河盆地新生界地层,得到固市凹陷基底深约8 100km,西安凹陷基底深约6 600km,固市凹陷明显比西安凹陷基底深,这是本次工作最大的成果之一。再结合收集的重力数据,经过消除莫霍面影响后,分析渭河盆地西安凹陷和固市凹陷整体重力场变化特征,结果表明造成西安凹陷重力低,但基底浅;固市凹陷重力高,但基底深。这种实际地质情况是由于西安凹陷新近系沉积地层比固市凹陷沉积地层厚且深,而古近系地层却较之薄而浅,这种"跷跷板"式的地层分布特征能够引起重力异常"非常规"现象出现。通过此次工作实践,对渭河新生代盆地的基底组成和结构构造有清楚认识,对评价重点勘查区的成藏条件,为渭河盆地氦气资源远景调查提供借鉴。  相似文献   

2.
从地球物理的角度出发,利用重力、磁法及电法勘探对河套盆地第四系深覆盖区展开深入研究,对河套断陷带南北边界断裂——鄂尔多斯北界断裂、色尔腾山前断裂的性质,河套盆地第四纪沉积物特征及厚度,河套沉积基底构造的探测进行了大量研究工作,并利用电法剖面对该区第四纪含水层分布规律进行了初步研究。通过重磁联合反演、天然地震数据,分析并推断了研究区由南向北的4条隐伏断层F1-F4及狼山-色尔腾山前大断裂F5,同时揭露了该区结晶基底的起伏及埋深,研究区南部基底深度2.5~4.2 km,北部中心基底最大埋深可达6 km,北部色尔腾山前断裂带迅速升至0~1 km。   相似文献   

3.
青藏高原中部古近纪发育伦坡拉盆地、色林错盆地、尼玛盆地,组成伦坡拉-色林错-尼玛沉积凹陷,总体呈近东西走向,长超过250km,宽30~50km;凹陷中心古近系河湖相沉积地层厚度达5~6km,下部为古新统-始新统牛堡组砾岩、砂岩、泥岩、泥灰岩,上部为渐新统丁青湖组泥岩、页岩、粉砂岩夹油页岩,顶部被新近系河湖相沉积不整合覆盖。凹陷南部发育尼玛-色林错逆冲推覆构造,凹陷北侧发育赛布错-扎加藏布逆冲推覆构造,伦坡拉盆地北部发育薄皮推覆构造,伴有不同规模的褶皱变形。地壳深部不同深度发育多重逆冲推覆构造,羌塘地块南部自北向南逆冲推覆,拉萨地块北部自南向北逆冲推覆;两者对冲部位地壳厚度发生显著变化,地表形成古近纪沉积凹陷。根据深地震反射及构造解释,结合Airy均衡分析,表明不同深度逆冲推覆及对冲构造运动导致地壳缩短增厚,增厚地壳均衡隆升及密度差异对古近纪沉积凹陷及盆地演化具有重要控制作用。色林错凹陷及邻区古近纪沉积记录对青藏高原地壳增厚与隆升过程具有重要指示意义。  相似文献   

4.
根据航磁测量资料,对四川盆地的磁场特征进行了分析,确定了盆地的边界及范围,并在编制四川盆地变质基底深度图、构造区划图的基础上,对盆地的基底结构、性质及其深度变化特点以及构造格局、盖层厚度等方面进行了研究。研究表明四川盆地基底由前震旦系变质岩系组成,埋深可达5~12 km,盖层为震旦纪一古生代和中新生代地层;盆地的发生和发展主要受NE向和近EW向构造制约,呈"四坳三隆"的构造格局。这些认识和结论,为今后在该盆地进行油气勘探提供了参考依据。  相似文献   

5.
综合物探方法在巴彦毛都盆地寻找砂岩型铀矿的应用   总被引:1,自引:0,他引:1  
通过在巴彦毛都盆地开展磁法、电阻率测深、自然电场法、^210Po等综合物探方法,基本查明了该盆地基底形态与埋深、盖层结构与找矿目的层发育特征、深部层间氧化带发育情况及铀矿化信息,为该盆地砂岩型铀矿远景评价提供了依据。  相似文献   

6.
北黄海盆地东部前中生界基底特征   总被引:6,自引:1,他引:5  
北黄海盆地是中国近海唯一未获得油气突破及勘探程度最低的含油气盆地(朝鲜已在该盆地东部实现了工业性油气突破),朝鲜在东部凹陷的3口钻井证实北黄海盆地东部凹陷主体前中生界基底是下古生界(Pz1)地层,与上覆以砂泥岩为主的中-新生界地层在地球物理特征上有很大差异,该特征提供了以地球物理资料推断和确定中-新生界盆地基底特征的可靠性。通过重力、磁力及大量多道地震资料解释认为,北黄海盆地前中生界基底最大埋深约5.5 km,凹陷主体部位前中生界基底以下古生界碳酸盐岩为主,其东北角可能存在上古生界碎屑岩基底,而凹陷南部可能是元古界浅变质岩基底。  相似文献   

7.
白勇  于国明  吴荣高 《地质通报》2010,29(8):1177-1184
为研究西藏措勤—洞错地区的地质结构,对2006年采集的1:50000重、磁剖面资料进行了分析、处理、曲线拟合计算与解释。结果表明,南端冈底斯基底走滑断隆带古生界褶皱基底很浅,缺失中生界;中部措勤盆地则埋深较大,最深可达9km,并表现为北深南浅的格局,主要充填了巨厚的中生界;北部班公湖-怒江缝合带的基底深度小于3km;剖面上羌塘地体的基底深度约3.5km。剖面中部措勤盆地北部坳陷与班公湖-怒江缝合带结晶基底磁性弱,北部和南部结晶基底磁性强。推断了12条断裂,其中F7断裂为措勤盆地北界,F1断裂为盆地南界。推断了6个花岗岩类岩体、2个蛇绿岩体及一套规模较大的火山岩,并描述了其地下赋存的特征。  相似文献   

8.
HQE爆破地震测线的地壳浅部的精细结构研究结果表明,上地壳的速度结构由疏松盖层、沉积层、加里东褶皱构造层及元古宙结晶基底等4个构造层构成,且大致以武夷山为界,宁都以西的低速凹陷区与中新生代沉积盆地相对应,加里东褶皱基底底部剧烈起伏,其最大埋深可达10km;而在宁都以东地区,地表速度明显增大,且加里东褶皱基底底界的深度明显变浅,仅为3~5km。笔者根据地壳浅部速度精细结构的变化特征对剖面沿线的构造单元进行了划分,并对邵阳盆地、衡阳盆地、茶陵盆地及泰(和)兴(国)盆地等盆地的分布范围、性质、基底及其主要地层分布进行了初步的分析和探讨。  相似文献   

9.
青藏高原中部色林错—伦坡拉逆冲推覆构造系统   总被引:1,自引:0,他引:1       下载免费PDF全文
通过野外地质观测结合地震反射剖面综合构造解释,在青藏高原中部色林错—伦坡拉古近纪沉积凹陷及邻区厘定3条较大规模的逆冲推覆构造,由逆冲断层、逆冲岩席、飞来峰、构造窗及伴生褶皱组成。沿班公—怒江缝合带发育赛布错—扎加藏布逆冲推覆构造,伦坡拉盆地北部发育双重推覆构造,拉萨地块北缘发育色林错—吴如错逆冲推覆构造,估算推覆距离分别为38~50 km。羌塘地块南缘自北向南逆冲推覆,拉萨地块北缘自南向北逆冲推覆,两者对冲导致色林错古近纪盆地及沉积地层发生比较强烈的褶皱变形,形成宽约20 km大型向斜构造。色林错—伦坡拉逆冲推覆构造运动开始时间为晚白垩世晚期,古近纪不同时期均发育逆冲断层,前锋逆冲断层和底部拆离滑脱构造主要形成时期为古近纪晚期—中新世早期。古近纪逆冲推覆构造对伦坡拉和色林错河湖相沉积盆地、烃源岩形成演化、油气成藏及保存条件具有显著控制作用。  相似文献   

10.
为了研究鄂尔多斯盆地西南缘基底特征,利用2016年在该地区获取的1∶5万高精度航磁资料和已有的1∶20万重力资料,推断了地壳断裂1条、基底断裂11条及中央古隆起的南部范围。采用重磁联合反演,大致了解了区内基底和盖层的埋深和厚度。应用欧拉反褶积和场源参数成像,分别用重力数据和航磁数据提取了区内奥陶系顶面的埋深信息和基底的埋深信息。研究表明:利用高精度航磁资料结合重力资料能够相对有效地识别基底特征。  相似文献   

11.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

12.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

13.
郯庐断裂南段研究进展与断裂性质讨论   总被引:13,自引:3,他引:13  
据1:5万区域地质调查和专题研究资料,就郯庐断裂带是否南延与消失的原因,其与大别—苏鲁造山带交截形成的假位错效应,以及与中新生代沉积盆地形成演化的关系等作了新的阐述。在此基础上,讨论了郯庐断裂带是否为巨大的左行平移断层或转换断层。认为郯庐断裂带可能是在“古郯庐带”的基础上于早侏罗世重新活动、白垩纪强烈活动的地堑型枢纽断裂带。  相似文献   

14.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

15.
塘口水电站大坝基础座落在断层和裂隙较发育的龟裂纹灰岩上,岩体完整性差、透水性强,多年运行后,大坝灌浆廊道和排水廊道出现多处集中性漏水,为确保大坝安全和电站正常发电,根据渗漏性质和成因,采用对灌浆廊道补充帷幕灌浆,对排水廊道进行固结+帷幕+回填灌浆。通过灌浆处理后,效果良好,表明灌浆工程有效的将导致坝基渗漏的上下游的裂隙通道封闭,并顺利的经受了随后的汛期洪水考验,大坝安全得到保障。  相似文献   

16.
某高速公路下伏煤矿采空区稳定性分析   总被引:10,自引:0,他引:10  
在论述某高速公路下伏砦脖煤矿采空区地质、采矿和工程地质特征的基础上, 进行了稳定性数值模拟分析, 定性与定量地分析与评价了该煤矿采空区的地表变形特征及稳定性。研究结果表明: 该煤矿采空区的变形尚未完成, 对拟建的高速公路将产生很大的危害, 必须采取相应的工程治理措施。   相似文献   

17.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

18.
In reservoir characterization, the covariance is often used to describe the spatial correlation and variation in rock properties or the uncertainty in rock properties. The inverse of the covariance, on the other hand, is seldom discussed in geostatistics. In this paper, I show that the inverse is required for simulation and estimation of Gaussian random fields, and that it can be identified with the differential operator in regularized inverse theory. Unfortunately, because the covariance matrix for parameters in reservoir models can be extremely large, calculation of the inverse can be a problem. In this paper, I discuss four methods of calculating the inverse of the covariance, two of which are analytical, and two of which are purely numerical. By taking advantage of the assumed stationarity of the covariance, none of the methods require inversion of the full covariance matrix.  相似文献   

19.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

20.
正Artemia cysts are an extremely important component of aquaculture diets.It is well established that the cultivation of fish and shellfish derive substantial health and growth advantages when Artemia are included in the diets of the  相似文献   

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