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111.
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桂北地区罗地1井钻探施工实践 总被引:1,自引:1,他引:0
页岩具有较强的水敏性,在页岩气勘查钻进施工中,井内易发生坍塌、剥落造成超径或缩径等井壁失稳现象。罗地1井采用金刚石绳索取心工艺进行钻进,完井井深1501.06 m,岩心采取率、井斜等各项指标均符合地质设计要求。本文主要从罗地1井的钻井设备、井身结构、施工难点等方面进行总结,可为今后页岩气调查井的施工提供参考。 相似文献
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声波钻进技术具有速度快、岩心保真好、适用地层广等优点,广泛应用于工程勘察、环境调查、浅源地热、基础工程、矿山治理等领域。为了提高声波钻进施工质量和过程控制,美国材料与实验协会于2004年制定了第一部声波钻进规程D6914—04,后经多次修订完善,形成最新声波钻进规程D6914/D6914M—16。本文根据该版规程内容,从技术原理、钻进设备、成孔工艺等方面展开了阐述。当振动器与钻柱谐振频率重叠时,声波钻头受到的能量达到峰值。钻机和取心钻具是声波钻进的核心设备。成孔工艺主要以双管高频振动、低速回转为主,实现多种目的层的原位取心作业。标准相关内容对声波钻进技术在我国的持续推广具有参考意义。 相似文献
115.
A New Reference Material for Tritium Organic Molecules in Sediment: Results of an International Intercomparison Exercise
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Phillip E. Warwick Ian W. Croudace Richard M. Marsh Nicolas Baglan Sang Bog Kim 《Geostandards and Geoanalytical Research》2018,42(2):253-262
Solid matrix 3H reference materials are challenging to prepare given the volatile nature of 3H and are often unrepresentative of the range of 3H forms that may be encountered during routine analysis. As a result, few 3H reference materials are currently available, undermining verification of analytical techniques for environmental 3H measurement. To address this, an International Working Group on Organically‐Bound Tritium Analysis determined to produce a tritium natural matrix reference material (NMRM). The reference material comprises marine sediment blended with sewage sludge contaminated with 3H‐organic species arising from authorised discharges from a radiopharmaceutical manufacturing site. Previous studies have demonstrated that the 3H species have persisted in the environment over three decades providing valuable supporting data to underpin the characterisation of the NMRM. The preparation and characterisation of the NMRM are described along with the subsequent application of the reference material in an international intercomparison exercise involving nineteen laboratories from nine countries. A reference value of 168 ± 22 Bq kg?1 was derived from the data arising from the proficiency test. 相似文献
116.
《China Geology》2018,1(2):187-201
Songke Well No.2, one of the main part of the scientific drilling project in Songliao Basin, which was drilled 7018 m and acquired the part of cores continuously from the Low Cretaceous to the Carboniferous and the Permian from the 2843 m deep, can be considered as the deepest continental drilling project in Asia. Aiming at the features of longer well sections, larger diameters and multiple spud-ins for coring of Songke Well No.2, this project broke through the “coring in small diameter and reaming in large diameter” spud-in drilling-completion procedures which are always used in large-diameter-well coring for continental scientific drilling projects in domestic and overseas and the drilling method of short-single-cylinder roundtrip footage. At the same time, “coring in the same diameter and completing drilling at one single diameter” was achieved at all φ311 mm and φ216 mm coring sections of more than one thousand meters long, high-efficient operation with “drilling long footage with drill tools combined in multi-cylinders” was achieved at deep coring section. Four world drilling records were created which include more than a thousand meters continuous coring at φ311 mm, and the footage per roundtrip footage at φ311 mm, φ216 mm and φ152 mm is all more than 30 m, all of these breakthroughs reduced at least 300 days for this project; moreover, considering the characteristics of formations that the geothermal gradient is high in the drilled sections and the inside-well temperature is over 240°C after drilling completion, a formate-polymer water-based mud system was developed by compounding attapulgite and sodium bentonite and by adding independently developed high-temperature stabilizer, which can provide critical technical support for successful well completion at 7018 m in the super-high-temperature environment It is the first time that the water-based mud is operated at the working temperature higher than 240°C in China; Besides, considering the high-quality requirement on cores imposed by the project, the method “mechanical cored is charge” to discharge core nondestructively on the ground was worked out, and more than 4000 m scatheless cores were discharged out of the drill pipes while maintaining original stratum structures. 相似文献
117.
河流景观生态学已成为河流科学研究与应用的新范式,但国内研究还颇为不足。从河流景观生态学发展的逻辑必然性、主要进程、基本内容与重要理论等方面进行了总结。结果显示,多尺度跨学科整体论河流认识要求和景观尺度上处理河流问题的实践需求共同推动河流景观生态学的迅速发展,其中心议题是河流物理景观系统与生物系统在不同等级尺度上的结构、格局与功能过程,尤其重视物理景观与不同等级生物系统的相互作用关系,对河流景观多尺度等级性、高动态性和有向性等突出性质的认识已取得重要理论发展。指出当前面临5个方面的核心议题亟需取得突破:改进和统一河流景观分类系统、河流景观跨尺度研究、河流景观方法对经典河流生态理论的再认识、河流景观机理与模拟、河流景观对气候变化与区域土地利用/覆被变化的响应研究。 相似文献
118.
Alessandro Amorosi Luigi Bruno Bruno Campo Bianca Costagli Wan Hong Vincenzo Picotti Stefano Claudio Vaiani 《Sedimentology》2021,68(1):402-424
Despite increased application of subsurface datasets below the limits of seismic resolution, reconstructing near‐surface deformation of shallow key stratigraphic markers beneath modern alluvial and coastal plains through sediment core analysis has received little attention. Highly resolved stratigraphy of Upper Pleistocene to Holocene (Marine Isotope Stage 5e to Marine Isotope Stage 1) alluvial, deltaic and coastal depositional systems across the southern Po Plain, down to 150 m depth, provides an unambiguous documentation on the deformation of previously flat‐lying strata that goes back in time beyond the limits of morphological, historical and palaeoseismic records. Five prominent key horizons, accurately selected on the basis of their sedimentological characteristics and typified for their fossil content, were used as highly effective stratigraphic markers (M1 to M5) that can be tracked for tens of kilometres across the basin. A facies‐controlled approach tied to a robust chronology (102 radiocarbon dates) reveals considerable deformation of laterally extensive nearshore (M1), continental (M2 and M3) and lagoon (M4 and M5) marker beds originally deposited in a horizontal position (M1, M4 and M5). The areas where antiformal geometries are best observed are remarkably coincident with the axes of buried ramp anticlines, across which new seismic images reveal substantially warped stratal geometries of Lower Pleistocene strata. The striking spatial coincidence of fold crests with the epicentres of historic and instrumental seismicity suggests that deformation of marker beds M1 to M5 might reflect, in part at least, syntectonically generated relief and, thus, active tectonism. Precise identification and lateral tracing of chronologically constrained stratigraphic markers in the 14C time window through combined sedimentological and palaeoecological data may delineate late Quaternary subsurface stratigraphic architecture at an unprecedented level of detail, outlining cryptic stratal geometries at the sub‐seismic scale. This approach is highly reproducible in tectonically active Quaternary depositional systems and can help to assess patterns of active deformation in the subsurface of modern alluvial and coastal plains worldwide. 相似文献
119.
高速远程滑坡物理模型试验中,岩石相似材料的选择是模型试验成功的关键,然而目前滑坡相似材料强度高、难以在缩尺试验中模拟滑坡破碎过程。以重晶石、石英砂为骨料,石膏为胶结剂,羧甲基纤维素钠、甘油、水作为辅助材料,进行可破碎岩石相似材料的配比试验。采用控制变量法研究重晶石与石英砂比例(重石比)、骨料与胶结物比例(骨胶比)、羧甲基纤维素钠含量、拌合水量、甘油含量对相似材料物理力学性质的影响。试验结果表明:所有配比情况下各相似材料物理力学参数的范围分别为单轴抗压强度为0.12~1.47 MPa,弹性模量为25.51~148.12 MPa,黏聚力为1.63~87.39 kPa,内摩擦角为22.70°~35.89°,脆性指标主要分布在0.033~0.145之间;重石比主要控制岩石相似材料的内摩擦角;骨胶比减小,对应的黏聚力和内摩擦角先增大后减小;羧甲基纤维素钠对材料的单轴抗压强度、弹性模量、黏聚力等材料的力学特性以及材料的脆性指标影响均比较大,其中对单轴抗压强度的影响最大。因此,控制羧甲基纤维素钠和拌合水量的含量,并合理调节重石比与骨胶比,在相似比约为1∶600的试验尺度下,最终确定了适用于高速远程滑坡碎屑化过程模拟的低强度高脆性岩石相似材料的配比区间。 相似文献
120.
在桩基领域,随着基础设施建筑对桩基础承载能力和桩孔垂直度的质量控制要求越来越高,现有常规桩基成孔监测技术已不能满足要求;在钻探领域,随着深井、超深井、科学钻探井及水平井的成井要求越来越高,由于地层因素、工艺技术等导致的实际钻孔轨迹偏离设计轨迹的井斜问题愈发突出,井斜的监控变得越来越严格,现有仪器已不能很好地满足钻孔轨迹测量的高精度要求。针对上述问题,本文梳理了随钻测斜技术发展现状,并结合地质岩心钻探、旋挖桩孔施工工艺特点,提出实现绳索取心钻探钻孔轨迹和大直径长钻孔灌注桩孔垂直度高精度实时监测的方案,这一思路的推广将对指导施工操作、保证钻孔/桩孔的整体质量产生积极影响。 相似文献