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1.
东海西湖凹陷保俶斜坡下第三系储层砂岩为长石岩屑砂岩或岩屑长石砂岩,杂基含量小于5%,矿物成分主要为伊利石和绿泥石;胶结物主要成分为高岭石、石英次生加大边、碳酸盐矿物,总含量小于10%.  相似文献   
2.
A detrital zircon aged 4.1 Ga is discovered by the SHRIMP U-Pb method in a quartzite in Burang County, western Tibet. This is presently the oldest single-grain detrital zircon in China. The Th-U ratios of the two testing points of the 〉4.0 Ga zircon are between 0.76 and 0.86, indicating their magmatic origin. This discovery has offered an important age for investigating the geological evolution of the Qinghai-Tibet Plateau.  相似文献   
3.
我国沿煤层定向钻进已掌握300m以内孔深的钻进工艺和技术关键,并完成了设备,仪器的配套,沿煤层定向钻进技术不仅可以用于煤矿井下的综合探测技术,探放水工程和瓦斯抽放施工,而且可用于地面其它近水平工程孔的施工,产生的经济效益和社会效益极其可观。  相似文献   
4.
The coarse-detrital deposits have the properties of cold accumulation and maintenance of cold for a long time. Now, at some place where the mean annual temperature of air is positive, one even can get the permafrost by artificial formation of the burial mound. According to these properties, some lowenergy storehouses are built for various purposes.  相似文献   
5.
论述了正常钻进的条件,提出了合理岩屑规程是保证正常钻进的关键和设计钻头的主要依据之一,讨论了岩屑规程与金刚石钻头唇面工作状态、孔底表面粗糙度和岩屑粒度的关系,提出了相应的建议。  相似文献   
6.
Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of various high-grade and multiply deformed rocks, including gray gneiss, basic granulite, amphibolite, fine-grained gneiss and marble, metamorphosed to upper amphibolite or granulite facies. It can be divided into four rock units: the Fuping TTG gneisses, Longquanguan augen gneisses, Wanzi supracrustals, and Nanying granitic gneisses. U-Pb age and Hf isotope compositions of about 200 detrital zircons from the Wanzi supracrustals of the Fuping Complex have been analyzed. The data on metamorphic zircon rims give ages of 1.82-1.84 Ga, corresponding to the final amalgamation event of the NCC, whereas the data for igneous zircon cores yield two age populations at -2.10 and -2.51 Ga, with some inherited ages scattering between 2.5 and 2.9 Ga. These results suggest that the Wanzi supracrustals were derived from the Fuping TTG gneisses (-2.5 Ga) and the Nanying granitic gneisses (2.0-2.1 Ga) and deposited between 2.10 and 1.84 Ga. All zircons with -2.51 Ga age have positive initial εHf values from +1.4 to +10.9, suggesting an important crustal growth event at -2.5 Ga through the addition of juvenile materials from the mantle. The Hf isotope data for the detrital zircons further imply that the 2.8 Ga rocks are important components in the lower crust, which is consistent with a suggestion from Nd isotope data for the Eastern Block. The zircons of 2.10 Ga population have initial εHf values of-4.9 to +6.1, interpreted as mixing of crustal re-melt with minor juvenile material contribution at 2.1 Ga. These results are distinct from that for the Western Block, supporting that the Fuping Complex was emplaced in a tectonic active environment at the western margin of the Eastern Block.  相似文献   
7.
The Qiongdongnan Basin and Zhujiang River(Pearl River) Mouth Basin, important petroliferous basins in the northern South China Sea, contain abundant oil and gas resource. In this study, on basis of discussing impact of oil-base mud on TOC content and Rock-Eval parameters of cutting shale samples, the authors did comprehensive analysis of source rock quality, thermal evolution and control effect of source rock in gas accumulation of the Qiongdongnan and the Zhujiang River Mouth Basins. The contrast analysis of TOC contents and Rock-Eval parameters before and after extraction for cutting shale samples indicates that except for a weaker impact on Rock-Eval parameter S_2, oil-base mud has certain impact on Rock-Eval S_1, Tmax and TOC contents. When concerning oil-base mud influence on source rock geochemistry parameters, the shales in the Yacheng/Enping,Lingshui/Zhuhai and Sanya/Zhuhai Formations have mainly Type Ⅱ and Ⅲ organic matter with better gas potential and oil potential. The thermal evolution analysis suggests that the depth interval of the oil window is between 3 000 m and 5 000 m. Source rocks in the deepwater area have generated abundant gas mainly due to the late stage of the oil window and the high-supper mature stage. Gas reservoir formation condition analysis made clear that the source rock is the primary factor and fault is a necessary condition for gas accumulation. Spatial coupling of source, fault and reservoir is essential for gas accumulation and the inside of hydrocarbon-generating sag is future potential gas exploration area.  相似文献   
8.
新疆岩石·岩屑·水系沉积物元素背景平均值   总被引:3,自引:0,他引:3  
论证了中国丰度及地壳表层物质成分研究的必要性和重要性,利用区域地球化学勘查所提供的高精度分析数据,经严格统计计算,发表新疆地区其一级构造单元表层岩石、岩屑、水系沉积物的39种元素背景平均值。  相似文献   
9.
周云宗 《地下水》1996,18(2):68-70
通过本文列举的实例表明,钻井中只根据岩屑判断地层岩性,局部与电测升曲线异常不符;在工程地质钻探中,由于岩芯磨损采取率低,单从岩芯判断地层岩性、目的层、含水层、软弱夹层的位置、厚度会出现偏差,给确定滤水管位置和工程地质中的软弱夹层带来困难。为此,开展综合性地球物理测井就能对上述出现的错误进行纠正和弥补,以便提高成井质量和工程地质钻探质量。  相似文献   
10.
杨荣平  蒋荣庆 《探矿工程》1992,(1):27-28,16
一、研究的必要性反循环钻进速度的快慢与许多因素有关,如钻孔深度、钻头结构、泵的吸程及安装高度等。能否迅速排除孔底岩屑对钻进速度有很大影响,排屑的快慢主要取决于循环液在钻杆内的上返速度。在钻杆内的上返速度最低值应大于岩屑在钻杆内的悬浮速度。为了寻求更符合反循环钻进岩屑颗粒悬浮速度的计算公式,作如下试验。  相似文献   
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