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941.
The accurate location of the injection-induced microearthquakes in German Continental Deep Drilling Program 总被引:1,自引:0,他引:1
Introduction The scientific drilling belongs to the International Lithosphere Program and is one of the four lithospheres explorations. So far there are more than ten countries, which have taken the scientific drilling. The German Continental Deep Drilling Program was later than the others and is the sec-ond deep drilling, but is the most significant scientific super deep drilling in the world. The Ger-man Continental Deep Drilling Program (Kontinentales Tiefbohrprogram der Bundesrepub… 相似文献
942.
943.
青藏高原第四纪重点湖泊地层序列和湖相沉积若干特点 总被引:3,自引:2,他引:1
本项研究对青藏高原代表性第四纪湖泊沉积区作了大范围调查,北自柴达木昆特依湖和昆仑山口、南抵江布-林芝,西起甜水海、东至迪庆.据青藏高原地质构造、沉积建造和地貌特点,将高原第四纪地层区划分为6个地层分区:藏南湖盆分区(Ⅰ)、羌塘高原湖盆分区(Ⅱ)(羌南湖盆亚区(Ⅱ-1)和羌北湖盆亚区(Ⅱ-2))、三江高山河谷分区(Ⅲ)、昆仑高山分区(Ⅳ)、柴达木、青海湖盆分区(Ⅴ)和阿尔金-祁连山高山区(Ⅵ).并对上述Ⅰ-Ⅴ分区第四纪湖相地层层序作了较详细划分和对比.从而指出青藏高原第四纪湖相沉积具有如下特点:①除了柴达木-青海湖盆分区外,其余各分区的湖滨剖面湖相碎屑沉积相对较粗,而同青藏高原属于全球第四纪最新隆起区相一致;②在湖盆区的湖相沉积常叠加或伴生冲洪积、风积相和冰碛或冰水沉积以及部分泥石流沉积、化学沉积与热水沉积.它们既反映青藏高原在第四纪隆升进入冰冻圈后湖盆沉积环境时有冷期发生,又反映高原隆升背景下,洪水期诱发山崩和泥石流堵塞成湖,或由于洪水泛滥,导致高原边缘内流湖决溃、湖泊消失(如Ⅲ、Ⅳ分区),还反映高原湖泊成盐过程与深部作用、强烈的新构造运动密切相关;③除了柴达木-青海湖分区(Ⅴ)和羌塘高原湖盆分区部分大型湖盆自第四纪以来有连续湖相沉积外,其他分区第四纪湖相沉积多不连续;④由于全新世青藏高原口趋干旱,除了一些现代积水湖盆外,有相当多湖泊干化,而缺失顶部湖相沉积.综上所述,为了获取青藏高原第四纪沉积连续环境记录,需选择高原内部或周边为数较少的新生代连续沉积盆地.本文论证了柴达木盆地是一个较理想的研究高原晚新生代湖相沉积区,建议在柴达木盆地实施晚新生代资源环境科学钻探工程. 相似文献
944.
945.
该文通过对钻孔灌注桩的主要施工工艺如:泥浆比重及粘稠度、孔内沉渣厚度、钢筋笼的制安以及水下混凝土的灌注等工艺技术要求的控制方法的阐述,指出在钻孔灌注桩施工过程中只要对这些工序加强控制,就能确保钻孔灌注桩的质量 相似文献
946.
G. Espinosa-Paredes A. Morales-Díaz U. Olea-González J.J. Ambriz-Garcia 《Marine and Petroleum Geology》2009
A strategy based on proportional-integral (PI) feedback control was applied to solve an inverse heat transfer problem for estimating static formation temperatures (SFTs) from logged temperatures in oil wells. The PI control feedbacks the error between logged and simulated temperatures during the shut-in time process, existing SFT proposal. Thus, mathematically speaking an inverse heat transfer problem was solved in this way, since SFT represents the initial conditions (which are unknown) to solve the partial differential equations governing the heat transfer process in the wellbore-formation system. The mathematical model considers transient convective heat transfer due to circulation losses to the rock surrounding a well. The methodology was tested analyzing two oil wells (MB-3007 and MB-3009) from the Gulf of Mexico and results were compared against two classic methods. The method presented in this work needs only one temperature measurement for each fixed depth to estimate the SFT. 相似文献
947.
Carlos E. Mendoza 《Mathematical Geology》1986,18(3):307-322
Data, each consisting of a unit vector and a position, are modeled as a smooth unit vector field plus random directional errors; the smooth unit vector field is estimated by fitting a spline to observations. The estimate is nonlinear; it is obtained with an iterative procedure in which, at each step, a least-squares smoothing spline is fitted to a set of pseudovalues. The resulting estimate is exemplified with a data set extracted from the literature in geology. The proposed estimate is compared, using the same data set with that obtained through suggestions of other authors, and is found to have attractive qualities. The use of plots of the resulting estimate to find the appropriate value of the smoothing parameter is emphasized throughout. 相似文献
948.
The palaeomagnetic standard technique of stepwise thermal demagnetization (STD), long regarded as unreliable for oceanic basalts that have undergone low temperature alteration, has recently been applied in a number of studies to characterize the natural remanent magnetization (NRM) of such rocks. In order to better understand STD data of oceanic basalts, and to possibly identify the magnetominerals that are carrying the NRM, we have carried out a number of continuous and STD experiments on seven oceanic basalt samples. During continuous thermal demagnetization (CTD), a sample is heated to a certain temperature and its NRM is measured during heating and subsequent cooling. Even when CTD reveals only titanomaghemite unblocking at 400°C as the remanence carrier, STD behaviour can be very complex and unblocking is observed at temperatures of up to 500°C and higher. CTD also allowed to identify a partial or full self-reversal of NRM due to interaction between two types of magnetominerals in one sample. The higher degree of maghemitization of smaller titanomaghemite grains with respect to larger ones, which are less efficient in carrying the remanence, was seen for three samples by a shift of 80°C between the strong field thermomagnetic curve and the NRM measured at elevated temperature. In several cases, the identification of the NRM-carrying magnetomineral was not possible from CTD data due to the ambiguity of Curie temperatures in the titanomagnetite/titanomaghemite system. 相似文献
949.
中国大陆科学钻探工程卫星孔PP6钻孔位于苏鲁超高压变质带的山东荣成滕家集马草夼橄榄岩体中。该橄榄岩出露于元古代花岗闪长片麻岩中,面积为300m×130m。地表岩石风化强烈,钻孔内岩石新鲜,劈理发育。孔深196m,橄榄岩厚度约110m,下部为花岗闪长片麻岩。橄榄岩主体呈块状构造,边缘呈条带状构造,靠近片麻岩的橄榄岩蛇纹石化强烈。除了10cm厚的岩脉原岩为岩浆分异的产物外,岩石主元素、微量和稀土元素地球化学显示,原岩为极亏损的地幔方辉橄榄岩。岩石主要矿物组成为橄榄石(85%~95%) 斜方辉石(3%~5%) 角闪石(3%~5%) 尖晶石(约0.5%) 镍硫化物(<0.1%),个别部位含有石榴石、单斜辉石和白云石。根据矿物的结构和成分,大体分为三个期次的组合。早期残余地幔矿物组合,由镁橄榄石、富铝顽火辉石、铬尖晶石和透辉石组成,具残余斑状结构,常含有包体,为高温低压组合;超高压变质期矿物组合,由镁橄榄石、镁铝榴石(Pyr=62~66)、低铝顽火辉石、铬尖晶石组成,具细粒变晶结构,无包体,变质温压为840~940°C、3.0~4.1GPa;麻粒岩相─角闪岩相变质期矿物组合,包括韭闪石、镁铝尖晶石、铬尖晶石、白云石、透闪石、蛇纹石,变质温度和压力为650~780℃、<1.8GPa。马草夼橄榄岩作为地幔楔,在印支期发生了超高压变质作用,并在折返过程中叠加了麻粒岩相-角闪岩相的变质作用。 相似文献
950.
福建煤田地质121队在福建、云南、贵州、四川等省份的复杂煤田勘探区推广应用绳索取心金刚石钻进技术,取得了较好的应用效果。通过分析云、贵、州、闽地区的地层特点,介绍了该类地区钻孔结构、冲洗液技术及护壁堵漏技术。在钻具配套、硬岩钻进等方面也进行了有效的探索,并以实例和大量数据说明121队在绳钻技术方面的应用水平。 相似文献