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91.
2004年2月14日巴基斯坦发生两次地震。第一次地震发生在当地时间2月14日15点20分(北京时间18时30分;格林尼治时间10时20分),震级为里氏5.7级,震中位于巴基斯坦西北边境省首府白沙瓦东北约200km的山区。约一个半小时后,同一地 相似文献
92.
为了探讨马克兰增生楔天然气水合物的主控因素,对收集的大量文献资料进行了整理和分析,发现马克兰增生楔由西到东、由南往北逆冲断裂的活动性具有逐渐减弱的趋势,BSR的振幅和连续性同样具有逐渐减弱的趋势,因此,马克兰增生楔BSR的产状主要受断裂构造的影响。马克兰增生楔沉积厚度大,SMI界面浅,水合物样品具有气泡结构以及BSR之下存在较厚的游离气表明,该区天然气水合物的气源充足。同时,低角度的北向俯冲造就的E—W向平行排列的南向逆冲断层以及小型正断层等为天然气向上运移提供了通道。由此可知,构造作用是马克兰增生楔天然气水合物的主控因素。 相似文献
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94.
外资管理、投资法及外资政策 我国周边大多数国家是在二次大战以后为发展民族工业,对外资进入本国矿业采取了诸多的限制措施。通常是把外资限制在比较低的水平,企业由本国人来管理,有些国家则根本不允许外资参与矿业。随着时代的变迁,特别是冷战的结束,各国纷纷打开国门,开放国内矿业市场。修改或制定新的外国投资法或相关法规自然成了这些发展中国家 相似文献
95.
巴基斯坦查盖火山岩浆岩带属于特提斯成矿域的重要组成部分之一,是巴基斯坦境内最重要的斑岩型铜矿带,但目前其相关的遥感研究还较少,制约了对该成矿带的找矿潜力分析。笔者等以山达克矿床及其周边为研究区,对先进星载热辐射与反射辐射计(Advanced Spaceborne Thermal Emission and Reflection Radiometer, ASTER)数据进行RBD (Relative absorption band depth)比值假彩色合成、主成分分析、光谱角制图等处理,获得蚀变遥感异常信息分布特征,通过对蚀变特征和主要控矿要素进行遥感研究,建立了山达克矿床遥感找矿模型并开展成矿预测,为该成矿带矿产勘查提供借鉴。根据建立的遥感找矿模型,圈定了找矿预测靶区10处。对矿区东矿体和矿区北部的2个靶区进行野外验证,证实了提取结果与实际地质事实吻合较好,对矿区岩石样品进行光谱实测,表明样品实测光谱曲线与标准矿物光谱曲线的吸收特征位置高度相似,证实了研究区绢云母化、青磐岩化等蚀变较强且分布较广。结果表明本次研究提取的矿化蚀变结果可信度较高,可为后续找矿勘查工作提供参考。 相似文献
96.
基性-超基性岩体广泛分布于巴基斯坦北部印度河缝合带和中南部碰撞带,发育有与蛇绿岩有关的铬铁矿床,多数岩体工作程度偏低。铬尖晶石是指示岩石成因和构造环境的有效标志。铬尖晶石矿物化学研究表明其岩体可划分为3类,其中尚拉-明戈拉、德尔盖、瓦齐里斯坦、穆斯林巴赫和贝拉岩体中造矿铬尖晶石的成分显示富Cr、贫Al、低Ti特征,副矿物铬尖晶石的Cr#变化范围指示其构造背景为大洋中脊向俯冲带之上的过渡环境,与我国罗布莎含矿岩体非常相似。通过对比分析典型豆荚状铬铁矿成矿地质特征和成矿规律,认为贝拉、穆斯林巴赫等岩体成矿条件有利,具较大找矿潜力。 相似文献
97.
Japanese threadfin bream Nemipterus japonicus(Bloch, 1791) is among the most abundant and commercially important species in Pakistan. From the coast of Pakistan, four demersal trawl surveys in October–November 2009 and May–June, August, October and November in 2010 were carried out. The purpose of this study is to estimate the population dynamics and status of the stock of the N. japonicus from Pakistani waters based on the research trawl surveys from the research area. The data consist of n=784 length-weight pairs and n=7 530 length frequency with the maximum length and weight of 29 cm and 358 g respectively. The length frequency data were analyzed using ELEFAN method in FiSAT computer package. The parameters of length and weight relationship were b=2.778, a=0.032 and R2=0.973. The estimated von Bertalanffy growth function parameters were L∞=30.45 cm, K=0.270 year-1. Based on length-converted catch curve analysis the total mortality(Z) during this study was estimated at 0.960 year-1. The natural mortality coefficient(M) was 0.74 year-1 using Pauly's equation(the annual average sea surface temperature was 27°C), therefore, the fishing mortality coefficients(F) were 0.22 year-1. The yield per recruit analysis indicated that when tc was 2, Fmax was estimated at 1.2 and F0.1 at 1.1. When tc was 1, Fmax was estimated at 0.95 and F0.1 at 0.8. Because current age at first capture is about 1 year and Fcurrent was 0.22, Fcurrent is smaller than F0.1 and Fmax, which indicated that the fishery is about in a safe condition. When using Gulland(1971) biological reference point, Fopt was equals to M(0.74). The current fishing mortality rate of 0.22 was smaller than the target biological reference point. 相似文献
98.
99.
Similar to other areas of Pakistan, land resources in Khyber Pakhtunkhwa (KP) is kept under various ownership regimes for socio-economic and ecological benefits. For the last three to four decades, communal lands and resources are subjected to high rate of degradation and deterioration, which is leading to multifarious socio-economical and ecological implications. This paper intends to look into factors that are responsible for the degradation of communal land and the adaptability of the management mechanisms developed by the local inhabitants to conserve these resources. Moreover, this study also explores the sustainability of these adopted strategies in present circumstances. Data regarding socio-economic parameters of the inhabitants and their interactions with communal lands were collected through questionnaire cum interview method. As long-term climatic data for the area do not exist therefore focus group discussions were conducted to document the changing trend in rainfall regimes and temperature variations for the last about four decades. Results indicate that communal lands are highly vulnerable to degradation due to biophysical and anthropogenic factors. Local inhabitants have developed suitable measures to control the situation, however, accelerated socio-economic transformations in the area have weakened the role of local institutions and that led to further degradation of these resources. Nevertheless, a number of locally formulated rules have been revived and implemented and it is hoped that these threatened resources would be conserved. 相似文献
100.
珠穆朗玛峰:世界第一高峰,海拔8848.13米,地处中尼边界东段,北坡在我国西藏境内,南坡在尼泊尔境内。乔戈里峰:世界第二高峰,海拔8611米,“乔戈里”是塔吉克语,意为“高大雄伟”,它是喀喇昆仑山脉的主峰,国外又称K2峰,位于喀喇昆仑山脉的中段,同时也是中国与巴基斯坦的国界线。 相似文献