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61.
We aim to show how some of the important interdisciplinary fixes or solutions to diverse problems observed in fisheries can complement each other. This can be achieved through methodical allocation of the rights pertaining to fisheries and simultaneous implementation of policy instruments to correct for market failures and equity concerns. We emphasize via a roadmap that there are some general principles that should be invoked when choosing between alternative structures of rights. Our examples from Sweden provide evidence of the flexibility of fishing rights and how they can be adapted to integrate fixes from different disciplines into practical fisheries management.  相似文献   
62.
测井评价煤层气储层的方法探讨   总被引:2,自引:0,他引:2  
根据煤层气储层实验室分析确定的体积模型(碳、灰分、挥发分、水分),以测井曲线予以评价。其中以自然伽马测井确定湿灰分,该方法的前提条件是湿分主要是泥质且泥质不具放射性元素;以密度测井与人工伽马测井确定含碳量,并对密度测井作湿分校正;以灰分校正后的密度测井确定饱和水孔隙度;含气量的估算以声波测井和密度测井组成的复合参数ΔT/dDEN来确定,或以视电阻率曲线确定含气量。以某地区2个钻孔为例,讨论了煤层深度、压力等与水分、灰分、含气饱和度、含气量等参数的关系,认为含气量与深度成正比关系。  相似文献   
63.
PSZJ-1声波全波列测井仪是煤炭系统首台小口径固井质量检查测井仪器,可用于测量自然伽马、套管接箍、声波时差、声幅、声波全波列五种参数。在固井质量检查测井时,根据声幅测井曲线的高(〉90%)和低(〈10%)以及声波变密度测井图上有无波形或波形的规则程度,可有效检查水泥环胶结质量,评价第一界面和第二界面的胶结情况。二个实例表明该仪器在固井质量检测中具有较好的应用效果。  相似文献   
64.
浅谈煤层气测井技术   总被引:2,自引:0,他引:2  
目前用于煤层气测井的主要设备有美国蒙特系列Ⅲ数字测井仪、渭南煤矿专用设备厂TYSC型和北京中地英捷物探仪器研究所PSJ-2型数字测井仪系统。煤层气裸眼井常测的参数有自然伽马、长短源距人工伽马、自然电位、双侧向、双井径、声波、补偿中子、井温、井斜等,而固井质量检查测井则用自然伽马、声幅、声波变密度和磁定位等方法。受井径过大的影响,密度三侧向测井、声速和补偿中子测井会存在较大误差。另外《煤层气测井作业规程》是单一企业标准,其中有些规定在实际执行过程中存在诸多问题,需在实践中进行修正。  相似文献   
65.
贵州五轮山井田自二叠系煤层形成以来,主要经历了三期构造应力场的更替。在构造控制下,煤层主要经历了四期煤化作用。煤层气主要生产阶段,发生在印支期末-燕山早期,保存的煤层气资源量巨大,据勘探资料推算,可采煤层的煤层气含量达到7.14—32.30m3/t·r。构造演化研究表明,自燕山期煤层气成藏以来,五轮山地区处于持续抬升剥蚀状态,煤层埋藏不断变浅,并发育了多组节理和断层。该区构造较为完整,煤层厚度较大,其主力煤储层层间距较小,盖层以泥岩为主,虽经多期构造改造,盖层仍保存完整,煤层较小,为煤层气的创造了条件。  相似文献   
66.
下入生产套管的煤层气U型井具有产气量高、成本低的优点,逐渐成为潘庄区块煤层气开发的主要井型。潘庄区块煤层埋深一般在500 m以浅,同时要求U型井的水平段在1000 m左右,生产套管的下入成为该区块垂深浅、水平段长的煤层气U型井的技术难题,经过多口井试验,优化钻井轨迹的平滑度,采用原钻具、短螺旋扶正器和生产套管内置钻铤3次划眼,以及严格控制下套管程序,可提高套管一次性下入的成功率,并提高生产效率。  相似文献   
67.
Fisheries management benefits from the contribution of several academic disciplines, each with their own perspectives, concerns and solutions. In this essay we argue that the contribution of biology, economics, sociology and other relevant disciplines to fisheries would be improved if they originated from broader, more integrated analytical perspectives that are attuned to the empirical realities of fisheries management. Today, disciplinary boundaries narrow the perspectives of fisheries management, creating tunnel vision and standardized technical fixes to complex and diverse management problems. Having worked separately and together for a number of years in fisheries research and consultancy in many parts of the world we, as a group of biologists, economists and sociologists, feel that the time to rid ourselves from disciplinary dogmatism is long overdue. We claim that improvements in fisheries management will be realized not through the promotion of technical fixes but instead by embracing and responding to the complexity of the management problem.  相似文献   
68.
Coalbed methane (CBM) development raises serious environmental concerns and concerted efforts have been made to collect chemistry, salinity, and sodicity data on CBM produced water. A model is sorely needed to make use of this data to quantify potential changes in stream water quality resulting from directly and/or indirectly receiving CBM produced water, on which little information is available in the literature. However, the application of existing hydrodynamic and water quality models such as CE‐QUAL‐W2 is not straightforward because the number of outfalls is usually large and the channels poorly defined for intermittent streams in semiarid areas such as the Powder River watershed, located in the states of Wyoming and Montana. Hence, the objectives of this study were to: (1) develop a CBM produced water routing (CBMPRO) model, and (2) apply the new CBMPRO model, along with a CE‐QUAL‐W2 model, to examine potential changes in stream water quality due to CBM development in the Powder River watershed. The CBMPRO model was developed and used to chart the CBM discharge and the transport of its associated constituents (e.g. total dissolved solids and alkalinity) from an outfall to its inclusive subwatershed outlet. In turn, the outputs from the CBMPRO model were applied as inputs into the CE‐QUAL‐W2 model to predict changes in the water quantity and quality along the Powder River mainstem. The results indicate that discharges from CBM developments adversely affect the stream water quality. Compared with the baseline conditions, the developments would increase the stream flows as well as make the stream water warmer and more saline. In addition, the impacts were predicted to undergo seasonal and spatial variations and to become smaller with time, as expected. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
69.
以研究区上古生界煤层气资源为主,通过收集已有地质勘查成果、地震剖面处理解释、测井资料再处理解释等资料,分析了煤层气成藏地质背景,恢复煤系地层的岩相古地理面貌。在此基础上,综合分析煤层气形成的地质条件,研究煤层气形成的主要控制因素和煤层气的赋存规律,采用单因素分析综合地质评价方法优选出上古生界煤层气的目的层段和有利区,为河南省煤层气勘查开发提供理论依据。  相似文献   
70.
温继伟  陈宝义  田巍 《吉林地质》2010,29(2):148-150,155
陕西省韩城市是陕西省主要的煤炭生产基地之一,煤层气资源丰富,含气饱和度较好,是理想的靶区。利用定向钻进技术开采煤层气具有开采成本低、煤层气产量高的优点。本文以韩城区块WL2-015向1井为例阐述了煤层气定向井钻井工艺,并总结了煤层气定向钻进的相关施工经验。  相似文献   
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