定向钻穿越技术在清江河天然气管道敷设的应用     

李效生  刘宪全 《安徽地质》2014,(1):56-59

清江河天然气管道工程是在河床下穿越1500多米的Φ1016×26.2天然气钢管和Φ114硅管套管。该河为通航河道,河底地面高程最低-5.90m左右,最大水深6.0~8.6m。地层为填土、淤泥质粘粉土、淤泥质粉砂、粉质粘土夹粉砂细砂。施工中通过优化施工方案,针对导向孔轨迹控制、淤泥地层定向钻进纠偏、大口径扩孔清孔和长输大口径管道回拖采取了一些有效的技术措施,确保了工程一次性回拖成功。  相似文献   

南海琼东南盆地深水区储层类型及研究意义   总被引：1，自引：1，他引：0       下载免费PDF全文

王艳 《沉积与特提斯地质》2014,34(3):82-87

通过对琼东南盆地钻井及典型地震相分析,认为琼东南盆地深水区发育两种类型的储层:第一类为形成于浅水环境的储层,包括扇三角洲砂体、滨浅海相滩坝砂体和台地碳酸盐岩;第二类为形成于深水环境的储层,包括盆底扇和峡谷水道等低位砂体。其中,深水区广泛分布的海底扇、峡谷水道砂体和台地碳酸盐岩具有良好的深水油气勘探潜力。  相似文献   

Accumulation of terrestrial organic carbon on an active continental margin offshore southwestern Taiwan: Source-to-sink pathways of river-borne organic particles     

《Journal of Asian Earth Sciences》2014

Sediment samples (213 sites) collected from the tectonic-active continental margin, offshore southwestern Taiwan were analyzed for grain sizes, organic carbon, nitrogen and carbon isotopic composition to obtain mass accumulation rate of terrestrial organic carbon and carbon budget to evaluate fate of terrestrial organic carbon from small mountainous rivers on the continental margin offshore southwestern Taiwan. Terrestrial organic carbon accumulation rates range from 0.29 to 45.6 g C m⁻² yr⁻¹ with a total accumulation budget of 0.063 Mt yr⁻¹, which accounts for less than 13% of total river particulate organic carbon loads exported from the adjacent rivers, the Gaoping (a.k.a., Kaoping), Erhjen and Tsengwen rivers. This low burial efficiency of terrestrial organic carbon demonstrated that a majority of river-borne particles together with organic materials was moved away from the study area.For the river-borne particles from the Gaoping river, a pair of depocenters in the upper slope flanking the Gaoping submarine canyon are the locations where the maximum TC_org accumulation rate were observed which hold up to 45% (0.016 Mt yr⁻¹) of the calculated accumulation found in the study region. On the other hand, the occurrence of higher-fraction terrestrial organic carbon in the upper and middle Gaoping submarine canyon suggests that a majority of particulate organic carbon of the Gaoping river was transported directly into the deep-sea basin through the Gaoping submarine canyon. Our results demonstrated that active margin with narrow shelf and slope is not an efficient sink for the large amount of terrigenous organic carbon supplied by the small rivers, but, a transient environment for these river derived particles.  相似文献   

湘西北海相含铀磷块岩中硒汞矿和晶质铀矿的发现及其地质意义   总被引：1，自引：0，他引：1  

漆富成  李治兴  张字龙 《铀矿地质》2014,(3):129-134,167

在扬子陆块东南缘湘西北武陵地区下寒武统牛蹄塘组海相黑色岩系下部鲕粒磷块岩中,首次发现了似纳米级的硒汞矿和晶质铀矿。通过电子探针化学成分测定和微区解剖,显示海相磷块岩中硒汞矿和晶质铀矿的产出状态、形态特征和占位特征。研究认为,同沉积期伴随火山热液喷出形成海相沉积鲕粒状磷块岩(鲕粒中包含球滴状硒汞矿),似纳米级硒汞矿在海相磷块岩中占位于鲕粒磷结核的内部和中心。其形成后期,海底热液作用持续,磷块岩经部分溶蚀、热液脱碳,在磷块岩的微裂隙中晶质铀矿、石英共沉淀析出。海相磷块岩中硒汞矿和晶质铀矿的发现和空间占位特征的研究,对探讨磷块岩中硒汞矿和晶质铀矿的形成与海底喷流(热水)沉积作用的发生方式和成因联系有启示意义,进一步佐证扬子陆块东缘陆缘裂陷喷气沉积是发生大规模铀成矿作用的机制。  相似文献   

与火山岩容矿有关的海底热水沉积矿床硫同位素地球化学证据     

徐文炘  李蘅 《矿产与地质》2014,(5):620-627

对国内与火山岩容矿有关的海底热水沉积矿床新疆阿巴宫、铁-铅锌矿、甘肃桦树沟铁-铜矿床、新疆阿舍勒铜锌矿、新疆阿尔泰可可塔勒铅锌矿等矿床硫化物进行硫同位素测定,这些矿床硫化物和硫酸盐的硫同位素组成分别为-4.3‰~1‰(阿巴宫)、+8.1‰~+33.4‰(桦树沟)、-3.3‰~+8.2‰(阿舍勒矿床硫化物)、-20.6‰~5.1‰(阿尔泰可可塔勒)。硫化物的硫同位素变化范围较小,硫同位素可以达到平衡,也可以没有达到平衡,获得的δ34SΣS值有+18‰~29‰之间,δ34SΣS值高;表明与火山岩控矿有关的海底热水沉积矿床热液中硫的来源,不是直接来源岩浆去气的硫,而是岩浆去气硫与海水硫酸盐硫混合而成的硫。  相似文献   

全球海底光缆传输网络的节点职能与鲁棒性评价     

章卓凡  张维阳  翟庆华  钱雨昕  陈硕 《世界地理研究》2022,31(5):929-940

海底光缆传输网络是全球信息传递和要素流动的重要基础设施支撑,国家或地区在全球海底光缆网络中的节点职能和对网络鲁棒性的影响事关国家信息通信安全。在此背景下,研究基于全球网络基础设施Infrapedia数据库,提取了1991—2017年近30年全球光缆分布数据,运用复杂网络分析方法,研究了不同国家或地区在全球光缆网络中承担“传输职能”和“枢纽职能”的特征及其演变,并探究了全球海底光缆网络的鲁棒性。研究发现：①国家或地区的信息传输职能和枢纽职能具有不同的模式;其中信息传输职能较为扁平化,且呈明显廊道格局,咽喉海峡沿线的国家或地区占据重要位置;信息枢纽职能具有明显的等级结构。②毗邻海峡的地缘战略位置、背靠强劲的国家实力、增长迅速的市场需求等共同塑造了全球海底光缆网络中的重要节点。③部分节点（尤其是高中间中心性的节点）发生故障会导致整个网络功能的大幅下降。研究从避免海底光缆链接的单一性、提升全球枢纽职能等方面提出了维护我国海底信息传输安全的启示。  相似文献   

浅谈大庆市地下管网普查整体解决方案     

郭子敏  吴琼 《测绘与空间地理信息》2014,(3):218-220

简要介绍了大庆市地下管网普查数据标准、管网建库标准和综合管线管理信息系统建设的一体化解决方案。  相似文献   

基于VOF方法的海底管道溢油扩散数值模拟研究     

李志刚  蒋梅荣  余建星 《海洋工程》2016,34(6):100-110

在海底输油管道运行过程中,管道渗漏、穿孔及破碎都会导致原油泄漏。对溢油运动的轨迹及其扩散范围作出预报可为溢油事故的处理提供及时、准确的信息,指导应急处理的正确实施。基于工程实际需求,采用有限体积法,结合k-ε紊流模型,建立了海流作用下海底输油管道溢油扩散数值模型。采用VOF方法(volume of fluid method)追踪多相流界面。首先,将数值模拟结果与Fan的实验值及Zheng和Yapa的数值结果进行了对比,验证数值模型的可靠性;其次,研究了不同原油溢出速度与环境水深对不同时刻溢油轨迹、到达海面时间、横向漂移距离与海面扩散范围的影响。研究表明:随原油溢出速度增大,溢油到达海面时间逐渐减小,溢油横向漂移距离与海面扩散范围则逐渐增大;随环境水深增大,溢油到达海面时间逐渐增大,且其变化接近线性分布。  相似文献   

Shallow‐water microbialite‐volcaniclastic facies association in the Cambro‐Ordovician Mt Windsor Subprovince,Australia     

M. G. Doyle  J. McPhie 《Australian Journal of Earth Sciences》2013,60(6):815-831

The Trooper Creek Formation is a mineralised submarine volcano‐sedimentary sequence in the Cambro‐Ordovician Seventy Mile Range Group, Queensland. Most of the Trooper Creek Formation accumulated in a below‐storm‐wave‐base setting. However, microbialites and fossiliferous quartz‐hematite ± magnetite lenses provide evidence for local shoaling to above fairweather wave‐base (typically 5–15 m). The microbialites comprise biogenic (oncolites, stromatolites) and volcanogenic (pumice, shards, crystal fragments) components. Microstructural elements of the bioherms and biostromes include upwardly branching stromatolites, which suggest that photosynthetic microorganisms were important in constructing the microbialites. Because the microbialites are restricted to a thin stratigraphic interval in the Trooper Creek area, shallow‐water environments are interpreted to have been spatially and temporarily restricted. The circumstances that led to local shoaling are recorded by the enclosing volcanic and sedimentary lithofacies. The microbialites are hosted by felsic syneruptive pumiceous turbidites and water‐settled fall deposits generated by explosive eruptions. The microbialite host rocks overlie a thick association (≤?300 m) of andesitic lithofacies that includes four main facies: coherent andesite and associated autoclastic breccia and peperite; graded andesitic scoria breccia (scoriaceous sediment gravity‐flow deposits); fluidal clast‐rich andesitic breccia (water‐settled fall and sediment gravity‐flow deposits); and cross‐stratified andesitic sandstone and breccia (traction‐current deposits). The latter three facies consist of poorly vesicular blocky fragments, scoriaceous clasts (10–90%), and up to 10% fluidally shaped clasts. The fluidal clasts are interpreted as volcanic bombs. Clast shapes and textures in the andesitic volcaniclastic facies association imply that fragmentation occurred through a combination of fire fountaining and Strombolian activity, and a large proportion of the pyroclasts disintegrated due to quenching and impacts. Rapid syneruptive, near‐vent aggradation of bombs, scoria, and quench‐fragmented clasts probably led to temporary shoaling, so that subsequent felsic volcaniclastic facies and microbialites were deposited in shallow water. When subsidence outpaced aggradation, the depositional setting at Trooper Creek returned to being relatively deep marine.  相似文献   

地震作用下可液化场地管道上浮动力响应及影响因素分析          下载免费PDF全文

顾世祥  张继虎  梅伟  杨帆  单夺权  童保林  杜文琪 《世界地震工程》2022,38(2):220-229

地震作用下土体发生液化之后,由于超静孔隙水压力的产生和土体抗剪强度的降低,管道易发生上浮破坏。为研究管道上浮动力反应的影响因素,基于OpenSees有限元软件,通过目标反应谱和谱匹配等方法选取地震波,考虑不同管土特性和地震动特性,对地震作用下管道上浮动力反应进行了二维数值模拟。结果表明:土体相对密度、管径和管道埋深对管道上浮反应的影响较大,分别给出了土体相对密度、管径、管道埋深对管道上浮位移的影响规律及对应拟合公式;长持时地震动作用下,超静孔隙水压力消散较慢,管道上浮位移可达短持时地震动作用下管道上浮位移的2倍左右;近断层脉冲地震动作用下,管道上浮破坏和横向破坏两种破坏模式同时存在,且由于速度脉冲效应,管道横向破坏风险大于上浮破坏风险。  相似文献