中国煤层气勘探开发技术研究进展

我国煤层气勘探开发工作走过了十多年的探索历程,大致可以分为三个阶段：技术引进阶段、勘探评价阶段、开发试验及探索研究阶段。目前,制约煤层气商业开发的瓶颈技术问题在于寻找煤层气富集高渗区、提高煤层气产能的开发工艺技术。本文将着重介绍我国在煤层气勘探开发技术方面的研究进展,主要包括煤层气资源评价和区块优选评价技术、钻井技术、完井工艺技术、压裂工艺技术、注CO2增产技术、煤层气地球物理探测技术、煤层气井抽放技术、煤层气生产和评价技术等等。同时,提出了今后我国煤层气勘探开发技术存在的问题和发展趋势。     

煤层气藏分析的参数与流程

煤层气藏特有的赋存状态、圈闭形式和不均一性决定了煤层气藏分析在煤层气勘探乃至开发中的重要地位.煤层气资源条件、煤储层岩石的不均一性程度是煤层气藏分析的重要方面.煤层气藏的分析评价应适应煤层气勘探开发的进程.在勘探初期评价选区阶段应以煤层气藏的地质条件分析为主.在进入井网试采阶段应突出煤层气藏分析, 特别是煤层气藏的不均一性分析.      

苏南煤层气的赋存规律及勘探靶区优选

根据苏南地区的含煤区地质背景、煤层分布、生气条件及含气量等的综合研究,总结了煤层气的聚集规律及影响因素,在此基础上建立适合本区地质实际的评价标准,并采用模糊综合分析方法,对22个煤层气勘探预选区块的勘探前景进行综合评价。研究表明,苏南地区煤炭资源分布小而零星,但从煤化阶段、煤岩组份、有机质类型等分析,总的煤层生气条件是好的。煤层含气量受埋深、煤种、煤厚、圈闭条件、水文地质条件等因素影响。根据本次煤层气选区评价结果,建议将港口、句容、花山三个区块作为煤层气勘探开发的首选区块,沙洲、东山、卜弋桥、湖塘、古洞等区块作为次选区块。     

多层次模糊数学在煤层气开发潜力评价中的应用

对影响煤层气勘探开发潜力的各种因素进行了综合研究,确定了煤层气勘探开发潜力评价的4个二级指标(含气丰度、封盖性能、开采条件和产气性能)及相应的三级指标。采用模糊数学方法对各级因素指标赋予了权重,建立了用于煤层气勘探开发潜力评价的多层次模糊数学评判模型。利用该模型,对川南盆地群煤层气资源条件较好的古叙、松藻、筠连和芙蓉4个无烟煤矿区的煤层气开发潜力进行了评价,认为松藻矿区是川南盆地煤层气勘探开发的最佳试验区。建立的评价体系,可以作为高煤阶煤层气资源开发潜力评价的参考体系。      

青海省天峻县木里煤田煤层气有利区块的 多层次模糊数学评判

对影响煤层气勘探开发潜力的各种因素进行了综合研究,确定了煤层气勘探开发潜力评价的3个二级指标(生气潜力、储层物性和封盖性能)及对应的三级指标。采用模糊数学方法对各级因素指标赋予权重,建立了用于煤层气勘探开发潜力评价的多层次模糊数学评判模型。利用该模型,对青海木里煤田中低煤阶煤层气资源勘探开发潜力进行了评价,认为江仓矿区是木里煤层气勘探开发的最佳试验区。所建立的评价体系可以作为中低煤阶煤层气资源开发潜力评价的参考体系。     

青海省天峻县木里煤田煤层气有利区块的多层次模糊数学评判

对影响煤层气勘探开发潜力的各种因素进行了综合研究,确定了煤层气勘探开发潜力评价的3个二级指标（生气潜力、储层物性和封盖性能）及对应的三级指标。采用模糊数学方法对各级因素指标赋予权重,建立了用于煤层气勘探开发潜力评价的多层次模糊数学评判模型。利用该模型,对青海木里煤田中低煤阶煤层气资源勘探开发潜力进行了评价,认为江仓矿区是木里煤层气勘探开发的最佳试验区。所建立的评价体系可以作为中低煤阶煤层气资源开发潜力评价的参考体系。     

滇东黔西煤层气选区及勘探目标评价

滇东黔西晚二叠世成煤期煤层气盆地发育,是华南重要的煤层气资源分布区,。本文概述煤层气盆地的划分与评价,提出煤层气系统的新概念,并对重点盆地进行研究。提出煤层气区带和煤层气地质风险分析的概念,并对滇东黔西地区重点区带进行煤层气藏预测及勘探目标优选,提出煤层气重点勘探开发试验区。     

徐州地区煤层气勘探地质条件及选区评价

根据徐州地区的含煤区地质背景、煤系分布、煤层特征及含气量等煤层气勘探地质条件的综合研究,分析了煤层气的控气地质因素,在此基础上建立了适合本区地质实际的评价标准,并采用模糊综合分析方法,对12个煤层气勘探开发预选区块进行评价。研究表明:徐州地区煤层总厚10~15 m,结构简单至复杂,含煤特征在空间展布上有着很大的差异;从煤层钻孔瓦斯含量来看,本区属于低沼气区,煤层气的赋存与煤阶、埋深、煤层厚度、构造类型、岩浆岩侵入、水文地质条件等因素有关;根据本次煤层气选区评价结果,建议将九里山区的QK7、QK9区块作为下一步煤层气勘探开发的首选区块。     

有关煤层气勘探评价的若干问题

煤层气的勘探评价,是开展煤层气勘探与开发工作的基础。当前要搞好勘探评价工作,需注意解决以下３个方面的问题：广泛搜集、认真总结国外煤层勘探开发的资料,精心筛选出适合我国国情的勘探评价参数体系;改进与完善煤层气勘探评价参数的测试技术,制定出与国际惯例相容的测试指南,为勘探评价提供准确的、可比性强的定量依据;做好勘探评价的经济财务分析工作,认真开展可行性研究评价,坚持综合勘探、综合评价原则。     

贵州西部煤层气开发前景分析

本文通过对贵州西部煤层气勘探开发的基础条件，开发优势及存在的问题进行分析，提出贵州西部煤层气勘探开发工作仍属风险勘探阶段，但试验性勘探开发的时机已经成熟，[通过政府的支持和各勘探单位的相互协作，能够取得阶段性的突破。     

Metallogenic Districts of Yangtze Cratonic Rim at the Edge of Chaos

Ｔｈｒｅｅｆｕｎｄａｍｅｎｔａｌｔｈｅｏｒｉｅｓａｒｅｒａｉｓｅｄｆｏｒ“ｃｏｍｐｌｅｘｉｔｙａｎｄｓｅｌｆ－ｏｒｇａｎｉｚｅｄｃｒｉｔｉｃａｌｉｔｙ（ＳＯＣ）ｏｆｍｅｔａｌｏｇｅｎｉｃｄｙｎａｍｉｃｓｙｓｔｅｍｓ”（Ｙｕ,１９９８）：（１）Ｎｏｎｌ...     

石门地区煤矿地质特征及其资源预测探讨

石门地区煤矿，主要为早二叠世栖霞早期煤层。全县共有７个赋煤区，本文对主要赋煤区的特征列表概要论述，并认为它属地台型含煤建造。指出３个“成煤带”的煤层均呈大透镜体产出，其间为无煤区。作者在煤矿资源预测中，对３个“成煤带”作了远景区划分，圈定与靶区预测，对石门地区的煤矿勘查和开发，具有指导意义。     

An Agricultural Land Resource Assessment Study Based on GIS—An Example from Guiyang City

This paper assesses the agricultural land resources of Guiyang City by means of GIS,on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicatror.he results suggest that most of the agricultural land resources are of good quality,However,there are 17.11km^2 dry land and paddy field,which belong to the region of serious heavy metal contamination and are not fit for planting crops.At the same time,the high quality plowland,which is suitable for cultivation,has decreased nearly by 1/3 due to soil heavy metal contamination.These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City.     

盐湖环境变化趋势与趋利避害

盐湖／湖泊是气候变化的一面镜子本文以国内外典型盐湖区地质灾害为案例。说明自然引起的盐湖地质灾害，人类在事先监测而掌握其变化趋势情况下，可趋利避害，减少损失程度。文中分析在中国西部气候可能由暖干向暖湿转型的情势下，中国盐湖的变化趋势，并就其近期湖水涨缩特点划分3种类型(湖水上涨型区、湖水下降型区和湖水上涨不稳区)。为了适应中国盐湖区气候一湖泊变化，提出在重要盐湖区增建和完善水文、气象观察站，并与遥感监测相结合；建立多学科、跨部门的近期西部盐湖区环境变化的重大基础项目。同时需在重点盐湖区增设防洪防旱水利设施工程、制定湖区生态保护措施等，在筑建盐田和基建工程时应充分考虑洪水泛滥的影响。     

辽西建平北部金矿TM信息提取及成矿预测

辽西建平北部金矿床和矿点分布集中 ,具有利成矿条件。通过对该区TM图像的遥感地质解译 ,提取了线性构造、环形构造及韧性剪切带构造信息 ;利用波段比值及主成分分析等数字图像处理方法 ,对区内重点地段进行金矿化蚀变信息提取处理 ,蚀变异常在图像上以彩色晕圈显示。研究表明 ,区内线环构造、韧性剪切带构造及蚀变异常发育的复合部位 ,是金矿成矿的有利地段。根据对本区金矿成矿条件的综合分析 ,在区内圈出了 3处金矿成矿预测区 ,并在野外验证中发现 3处金矿点 ,取得了较好的找矿效果。     

Seismic demands and analysis of site effects in the Marmara region during the 1999 Kocaeli earthquake

The characteristics of the strong ground motion accelerograms from the 1999 Kocaeli earthquake are investigated in detail in this study. The emphasis is on the comparison of the response spectra for the fault normal (FN) and fault parallel (FP) components of the ground motions. The results show that the near-fault records with directivity effects characterize themselves with increased base shear demands rather than increased displacement demands for both the FN and FP components and a narrower velocity sensitive region for the FN component. This study also shows that the effectiveness of base isolation may vary from site to site and for a given site, from component to component. The site effects in the Marmara region during the 1999 Kocaeli earthquake are examined. Site amplifications are predicted by the classical spectral ratio (CSR) and the receiver function (RF) methods. The CSR method gives higher estimates for the site amplifications compared to the RF method and is in better conformity with the observed damage during the Kocaeli earthquake. The districts of Istanbul that are especially susceptible to site amplification hazard are determined. It is apparent from the results that the site amplification hazard risk is the highest for Avcilar and Bakirkoy districts. This study also shows that for sites which have the risk of soil amplification for long-period structures, liquefaction may not be beneficial as a natural base isolator, and may result in shifting the eigenperiod of the low- and mid-rise structures to the critical periods with high site amplifications. This may be especially the case for Avcilar and Bakirkoy districts. In Fatih, Bakirkoy, and Cekmece districts, the predominant period of the ground motion is calculated to be very close to the eigenperiods of the typical residential buildings. Therefore, these three districts are expected to experience heavier damages in future earthquakes due to resonance effects.     

西藏谢通门县普迟亚地区高精度磁测成果及找矿方向

通过1:5万地面高精度磁测的实地调查,对工作区的磁场特征有了详细的了解.经磁异常的定性分析,筛选出11个找矿潜力较大的异常区.同时1:5万水系沉积物测量成果表明区内主要找矿元素为Cu、Pb、Zn.磁异常的定性分析对这些金属矿的深部找矿预测可以提供有利证据.结合化探异常、地质特征、矿化特征优选出了展咱木部-坑马勒间强磁异...     

Genesis of Early Cretaceous porphyrite-type iron deposits and related sub-volcanic rocks in the Ningwu Volcanic Basin,Middle-Lower Yangtze Metallogenic Belt,Southeast China

ABSTRACT

The Ningwu Volcanic Basin (NVB), located in the Lower Yangtze Metallogenic Belt, is characterized by the widespread occurrence of porphyritic iron-ore deposits. These deposits are clustered in three areas within the basin: the northern, central, and southern districts. Our study shows that the differences are existed in geochemistry of the rocks and the mineralization of the deposits among these three districts. Though results of Sr–Nd isotopes indicate that the parental magma of the sub-volcanic rocks in NVB were derived from EMI and EMII, however, the sub-volcanic rocks from the northern and southern districts have higher ε_Nd(t) values (t = 130 Ma) and lower initial ⁸⁷Sr/⁸⁶Sr ratios (t = 130 Ma) than those from middle district. The rocks from northern and southern districts are similar to EMI in geochemistry; in contrast, rocks from the middle district are close to EMII. Meanwhile, the deposits from different districts show some differences in mineralization. The magnetites from the northern ore deposits are rich in Cu, Mo, Zn, and Mg and poor in Ca, Al, and Ti, which probably indicates that the magnetites from the northern ore deposits closer to hydrothermal genesis than to magmatic genesis, but the magnetites from the centre are closer to both magmatic and hydrothermal geneses. Based on the fact that a part of the sub-volcanic rocks is closer to EMI and another part to EMII in geochemistry, we suggested that the incorporation of the lower and upper crustal materials into the source regions of the sub-volcanic rocks has taken place by different manner and processes. Integrated with analysis of the tectonic evolution of NVB, we come to the conclusion that the sub-volcanic rocks have recorded the geochemical imprints of the subduction of Yangtze block towards North China block during Indosinian Period and the delamination of the lower crust of Yangtze block during Yanshanian Period.     

Classification of cyclone hazard prone districts of India

Hazards associated with tropical cyclones are long-duration rotatory high-velocity winds, very heavy rain and storm tide. India has a coastline of about 7,516?km of which 5,400?km is along the mainland. The entire coast is affected by cyclones with varying frequency and intensity. The India Meteorological Department (IMD) is the nodal government agency that provides weather services related to cyclones in India. However, IMD has not identified cyclone-prone districts following any specific definition though the districts for which cyclone warnings are issued have been identified. On the other hand, for the purpose of better cyclone disaster management in the country, it is necessary to define cyclone proneness and identify cyclone-prone coastal districts. It is also necessary to decide degree of hazard proneness of a district by considering cyclone parameters so that mitigation measures are prioritised. In this context, an attempt has been made to prepare a list of cyclone hazard prone districts by adopting hazard criteria. Out of 96 districts under consideration, 12, 45, 31 and 08 districts are in very high, high, moderate and low categories of proneness, respectively. In general, the coastal districts of West Bengal, Orissa, Andhra Pradesh and Tamil Nadu are more prone and are in the high to very high category. The cyclone hazard proneness factor is very high for the districts of Nellore, East Godawari, and Krishna in Andhra Pradesh; Yanam in Puducherry; Balasore, Bhadrak, Kendrapara and Jagatsinghpur in Orissa; and South and North 24 Parganas, Medinipur and Kolkata in West Bengal. The results give a realistic picture of degree of cyclone hazard proneness of districts, as they represent the frequency and intensity of land falling cyclones along with all other hazards like rainfall, wind and storm surge. The categorisation of districts with degree of proneness also tallies with observed pictures. Therefore, this classification of coastal districts based on hazard may be considered for all the required purposes including coastal zone management and planning. However, the vulnerability of the place has not been taken into consideration. Therefore, composite cyclone risk of a district, which is the product of hazard and vulnerability, needs to be assessed separately through detailed study.     

Resources Conditions of Coalbed Methane Districts in China

The China National Administration of Coal Geology accomplished an assessment of coalbed methaneresources of China in 1988. The total amount of coalbed methane resources in China is 14336.944 billion m , occurring in recoverable coal seams and beneath weathering zones, with coalbed methane content equal to or higher than 4 m3 per ton and buried depths smaller than 2000 m, among which there are 967.51 billion m of predicted reserves and 13369.434 billion m of future reserves. The resources in coal reservoirs with methane content of more than 8 m per ton are 12444.087 billion m , and those with methane content between 4 to 8 m per ton are 1892.856 billion m . There are 35 districts in which the resources abundance is higher than 150 million m3 /km2 , 49 districts with the abundance between 50 million and 150 million m 3/km2 , and 31 districts with the abundance less than 50 million m3 /km2 . There is 9256.078 billion m3 of methane occurring in coal seams with buried depths less than 1500 m, and 5080.866 bi