冻土区天然气水合物研究现状与内蒙古多年冻土区地质条件概述

天然气水合物是一种资源量丰富的新型能源。本文概述了国内外冻土区天然气水合物的最新研究进展,简要介绍了内蒙古自治区多年冻土的分布情况和地质概况,认为根河-拉布达林一带多年冻土区具备天然气水合物赋存条件,并提出了内蒙古多年冻土区天然气水合物勘查开发建议。     

北极阿拉斯加北坡盆地天然气水合物成矿 规律与资源潜力

北极阿拉斯加北坡盆地是全球开展天然气水合物的调查研究最早的地区之一,对全球天然气水合物的研究具有示范作用。在大量文献资料综合分析的基础上,本文系统归纳了阿拉斯加北坡地区天然气水合物的成矿地质条件和成矿规律。认为阿拉斯加北坡的天然气水合物成矿系统是下伏下白垩—第三系含油气系统在浅部的衍生,是由下伏气源、断裂、岩性、北极的特殊环境(永久冻土、地层温压场)等多种因素共同作用的结果。通过模拟计算和分析,将阿拉斯加北坡地区划分了3级远景资源区,估算出整个阿拉斯加地区的天然气水合物资源为6.0×1012m3标准天然气,其中I级远景区主要分布于阿拉斯加北坡的滨岸冻土区和陆架区,资源量为2.83×1012 m3标准天然气。     

极地天然气水合物勘探开发现状及对我国的启示

极地天然气水合物分布于南北极大陆及其毗邻海域的沉积物（岩）中,与广泛分布的永久冻土带密切相关,资源潜力巨大。极地天然气水合物储层类型主要为富砂沉积物储层,能提供天然气水合物高浓度聚集所需的储集渗透性,最可能实现远景勘探和商业利用。随着全球气候变暖,北冰洋海冰加速融化和航道开通,北极地区蕴藏的丰富资源都将从潜在利益变成现实利益,各国的权益纷争也将愈演愈烈。本文综述了极地天然气水合物勘探开发现状和相关国家的水合物开发政策,依据中国海陆域天然气水合物勘查开发现状,提出了中国参与极地天然气水合物研究和开发的思路和途径,为中国极地资源开发利用战略提供参考。     

极地天然气水合物勘探开发现状及对中国的启示

极地天然气水合物分布于南北极大陆及其毗邻海域的沉积物(岩)中,与广泛分布的永久冻土带密切相关,资源潜力巨大。极地天然气水合物储层类型主要为富砂沉积物储层,能提供天然气水合物高浓度聚集所需的储集渗透性,最可能实现远景勘探和商业利用。随着全球气候变暖,北冰洋海冰加速融化和航道开通,北极地区蕴藏的丰富资源都将从潜在利益变成现实利益,各国的权益纷争也将愈演愈烈。本文综述了极地天然气水合物勘探开发现状和相关国家的水合物开发政策,依据中国海陆域天然气水合物勘查开发现状,提出了中国参与极地天然气水合物研究和开发的思路和途径,为中国极地资源开发利用战略提供参考。     

中国西部天然气资源和勘探开发前景

前言在行政划分上,西部地区指西北地区和西南地区,包括陕西、甘肃、内蒙、宁夏、青海、新疆、西藏、四川。在地质上,广义的西部地区指包括鄂尔多斯盆地和四川盆地在内的以西领域。为了与“西部大开发”所指的地区和领域相匹配,本文在研究天然气资源分布状况的西部地区指广义上的西部地区,包括天然气地质研究中的中部区和西部区。近年来,在西部地区相继发现了一系列大中型气田,特别是以克拉2号为代表的世界级大型气田的发现促使了“西气东输”工程的启动。该项工程的实施意义重大,不但对我国东部地区经济建设提供洁净能源、改善能源消耗结构、保护环境,而且对开发西部丰富的天然气资源,变资源优势为经济优势具有十分重要的意义。     

天然气水合物勘查技术研究进展综述

天然气水合物是天然气和水在特定条件下形成的一种新型能源矿产,是未来的战略性能源。本文根据国内外研究成果,总结归纳了天然气水合物的地震法、地球化学法、地球物理测井和其他方法等勘查技术的原理和优缺点。提高天然气水合物勘查技术的方法研究,有利于推进我国天然气水合物的研究和开发进展。     

我国海域“可燃冰”调查勘查技术体系形成

<正>不久前,南海天然气水合物钻探工程在广州通过验收。由李廷栋、陈毓川、张洪涛等院士和专家组成的验收组认为,本次钻探在圆满完成规定的各项外业任务基础上,实现了天然气水合物开发利用领域的又一次重大突破。至此,我国正式形成海域天然气水合物从调查评价到钻探阶段的方法技术体系,为大面积开展海域天然气水合物资源调查评价和勘查,奠定了坚实的技术基础。     

南极陆缘热流分布与天然气水合物资源量研究

近期系统的研究表明南极陆缘存在众多有利于天然气水合物赋存的指示性标志,尤其在陆缘周围的盆地中发现多条相关的地球物理反射层;同时,物源、温压、构造和沉积条件,皆有利于来自下部烃类气体的运移、富集和成藏,形成适合天然气水合物赋存的构造环境。在此基础上,利用收集的地热数据库,首先描述了陆缘周围的热流分布状况,再次计算了天然气水合物稳定带的厚度,最后利用体积分方法初步估算了该区域的天然气水合物的前景资源量。结果表明虽然陆缘周围的热流值相对较高,平均值达85.9 mW·m^-2,但是由于陆缘海水深度大,形成足够强的压力,保证了天然气水合物的稳定赋藏,由此计算的前景资源量为0.97－1.63×10¹³ m³,表明具有可观的经济价值。     

基于玛纳斯河流域生态问题的生态安全评价

 玛纳斯河流域山地-绿洲-荒漠三大生态系统表现出区域生态、经济要素的空间状况有所分异,经过几十年大规模的水土资源开发,流域不同的生态经济功能分区在环境演变和经济发展过程中所存在的生态安全问题的表现形式也各不相同。根据流域土地利用和水资源数据库,并参考各地自然、经济、社会统计资料,在生态经济功能分区的基础上,针对流域不同分区存在的生态经济安全问题选取相应的生态安全评价指标,结合实地调研和专家赋值法确定不同指标的权重,并计算综合生态安全评价指数,对流域各个生态经济功能亚区进行生态安全评价。评估结果表明：（1）玛纳斯河流域分为3个一级区和9个二级分区,根据不同分区存在的生态安全问题选取了13个生态环境指标和4个社会经济指标;（2）Ⅱ4、Ⅲ1和Ⅲ2亚区的生态不安全指数呈上升趋势,Ⅲ3亚区逐渐下降,Ⅰ1、Ⅰ2、Ⅱ1、Ⅱ2和Ⅱ3亚区存在波动,而对于绿洲区的四个亚区而言,Ⅱ2亚区生态不安全指数最高,存在的生态安全问题最多,而Ⅱ3亚区虽地处沙漠边缘,生态不安全指数相对最低,因此生态不安全指数高的区域需要高度重视,不高的区域由于生态问题会带来诸多不利影响,也需要重视。     

南海诸岛的自然环境、资源与开发——纪念中国政府收复南海诸岛70周年(3)

结合近百年几代科学工作者在南海诸岛开展的自然科学调查研究,从区域地质地貌、气候、海洋水文、海洋生物、陆地生物、土壤、自然综合体和自然区划等方面对南海诸岛的自然环境进行了综合阐述;继而从国土资源、渔业资源、旅游资源、油气资源和天然气水合物资源、灰沙岛陆地生物资源和水资源、港口航道资源及海洋―大气能资源等方面对南海诸岛拥有的自然资源进行了详细解释。在此基础上,结合其自身禀赋、战略地位的重要性,提出了科学开发南海诸岛的策略。南海诸岛的开发,除了大力发展旅游业、捕捞业和环礁潟湖养殖业外,应重点推进海洋油气和天然气水合物资源勘探与开发。     

Spatial coupling relationships of gas hydrate formation in the Tibetan Plateau

At present, gas hydrates are known to occur in continental high latitude permafrost regions and deep sea sediments. For middle latitude permafrost regions of the Tibetan Plateau, further research is required to ascertain its potential development of gas hydrates. This paper reviewed pertinent literature on gas hydrates in the Tibetan Plateau. Both geological and ge- ographical data are synthesized to reveal the relationship between gas hydrate formation and petroleum geological evo- lution, Plateau uplift, formation of permafrost, and glacial processes. Previous studies indicate that numerous residual basins in the Plateau have been formed by original sedimentary basins accompanied by rapid uplift of the Plateau. Ex- tensive marine Mesozoic hydrocarbon source rocks in these basins could provide rich sources of materials forming gas hydrates in permafrost. Primary hydrocarbon-generating period in the Plateau is from late Jurassic to early Cretaceous, while secondary hydrocarbon generation, regionally or locally, occurs mainly in the Paleogene. Before rapid uplift of the Plateau, oil-gas reservoirs were continuously destroyed and assembled to form new reservoirs due to structural and thermal dynamics, forcing hydrocarbon migration. Since 3.4 Ma B.P., the Plateau has undergone strong uplift and extensive gla- ciation, periglacier processes prevailed, hydrocarbon gas again migrated, and free gas beneath ice sheets within sedi- mentary materials interacted with water, generating gas hydrates which were finally preserved under a cap formed by frozen layers through rapid cooling in the Plateau. Taken as a whole, it can be safely concluded that there is great temporal and spatial coupling relationships between evolution of the Tibetan Plateau and generation of gas hydrates.     

论青藏高原范围与面积

长期以来 ,种种因素导致学者们对青藏高原确切范围的认识和理解存在差异。根据青藏高原相关领域研究的新成果和多年野外实践 ,从地理学角度 ,充分讨论了确定青藏高原范围和界线的原则与涉及的问题 ,结合信息技术方法对青藏高原范围与界线位置进行了精确的定位和定量分析。得出 :青藏高原在中国境内部分西起帕米尔高原 ,东至横断山脉 ,横跨 31个经度 ,东西长约 2 94 5km ;南自喜马拉雅山脉南缘 ,北迄昆仑山 -祁连山北侧 ,纵贯约 13个纬度 ,南北宽达 15 32km ;范围为 2 6°0 0′12″N～ 39°4 6′5 0″N ,73°18′5 2″E～ 10 4°4 6′5 9″E ,面积为 2 5 72 4× 10 3km2 ,占我国陆地总面积的 2 6 8%。     

Studies on frozen ground of China

Permafrost in China includes high latitude permafrost in northeastern China, alpine permafrost in northwestern China and high plateau permafrost on the Tibetan Plateau. The high altitude permafrost is about 92% of the total permafrost area in China. The south boundary or lower limit of the seasonally frozen ground is defined in accordance with the 0 oC isothermal line of mean air temperature in January, which is roughly corresponding to the line extending from the Qinling Mountains to the Huaihe River in the east and to the southeast boundary of the Tibetan Plateau in the west. Seasonal frozen ground occurs in large parts of the territory in northern China, including Northeast, North, Northwest China and the Tibetan Plateau except for permafrost regions, and accounting for about 55% of the land area of China. The southern limit of short-term frozen ground generally swings south and north along the 25o northern latitude line, occurring in the wet and warm subtropic monsoon climatic zone. Its area is less than 20% of the land area of China.     

Studies on frozen ground of China

1ThestatusoffrozengroundinChinaBased on previous studies, Zhou and Guo (1982) summarized the distribution characteristics of permafrost in China and indicated that the permafrost area in China is about 215×104 km2, in which about 163.4×104 km2 is on the Tibetan Plateau. After mapping and zonation of frozen ground in 1983, Xu and Wang suggested that the areas of permafrost, seasonally frozen ground and temporal frozen ground in China were 206.8×104 km2, 513.7×104 km2 and 229.1×104 km2 …     

中国冻土研究进展

Permafrost in China includes high latitude permafrost in northeastern China, alpine permafrost in northwestern China and high plateau permafrost on the Tibetan Plateau. The high altitude permafrost is about 92% of the total permafrost area in China. The south boundary or lower limit of the seasonally frozen ground is defined in accordance with the 0 ℃ isothermal line of mean air temperature in January, which is roughly corresponding to the line extending from the Qinling Mountains to the Huaihe River in the east and to the southeast boundary of the Tibetan Plateau in the west. Seasonal frozen ground occurs in large parts of the territory in northern China, including Northeast, North, Northwest China and the Tibetan Plateau except for permafrost regions, and accounting for about 55% of the land area of China. The southern limit of short-term frozen ground generally swings south and north along the 25° northern latitude line, occurring in the wet and warm subtropic monsoon climatic zone. Its area is less than 20% of the land area of China.     

青藏高原风沙堆积对多年冻土影响研究进展

受全球气候变化和人类活动影响,青藏高原上的土地沙漠化正呈现加速发展态势。沙漠化产生的风沙堆积势必改变地表辐射和能量平衡状况,对较为敏感和脆弱的多年冻土环境造成影响,并可能影响青藏铁路路基的稳定性。因此,研究积沙对多年冻土的影响对于高原沙害防治、多年冻土保护和道路工程建设都具有重要的理论及现实意义。目前,前人已在青藏高原地表能量平衡研究方面取得了一些成果,并开始关注积沙对冻土温度影响问题。然而,由于已有观测资料的连续性、同步性和可比性等局限,对积沙地表辐射和能量平衡方面的研究还比较薄弱,积沙对冻土温度过程影响的研究结果尚不一致,而积沙对路基影响的问题也亟待开展研究。为此,本文提出了加强定位观测、开展室内低温实验以及数值模拟等建议,以期对今后的深入研究起到抛砖引玉作用。     

Permafrost in Qinghai Province: Characterization and impact on transportation construction

Through a long-term summary of highway construction in the permafrost regions of Qinghai Province, the formation conditions and distribution characteristics of permafrost and their impact on transporta...     

Historical Overview of Permafrost Studies in China

Although soil freeze/thaw phenomena were reported centuries ago in the historical Chinese literature, systematic study of permafrost in China started in the 1950s. Permafrost research in China has been related to the exploration for and economic development of natural resources. Intensive investigations for several decades culminated in 2000 in the publication of a detailed map of geocryological regionalization and classification. From this map, it is estimated that permafrost covers approximately 23% of the country. About 80% of China's permafrost is mountain permafrost. China contains about 74.5% of the mountain permafrost area of the northern hemisphere. Since the early 1960s, researchers in China have conducted numerous field campaigns to determine permafrost and ground-ice distribution. A comprehensive ground-based and long-term monitoring network has been established on the Tibetan Plateau and in northeastern China. The State Key Laboratory of Frozen Soil Engineering (SKLFSE) was established in 1991 and is open to national and international engineers and scientists to conduct related studies and experiments. Numerous field and laboratory experiments, as well as numerical modeling, have been conducted to meet the requirements for industrial design, construction, and operation in permafrost regions. Rescuing, archiving, and distributing historical permafrost data would greatly aid the ability of scientists to assess long-term changes in permafrost and its potential influence on the natural and engineered environment. Chinese geocryologists and engineers are facing new challenges with the construction and future operation of the Qinghai-Xizang railroad that will cross 550 km of permafrost on the Tibetan Plateau.     

Diversification of Livelihoods in a Society in Transition: A Case Study of Tibetan Communities in Southwest China

In recent years, large development and market integration programs have altered the socioeconomic structures and cultural identity of rural communities and ethnic minorities in Southwest China and influenced the management of natural resources. This article analyzes livelihood strategies in the Shuiluo Valley, a remote area of the Sino-Tibetan borderlands. Agricultural activities and the management of natural resources were studied in five villages of Muli Tibetan Autonomous County, Sichuan Province. Characteristic for rural societies in transition, livelihoods were found to be flexible, combining subsistence agriculture, off-farm employment, and the exploitation of both renewable and nonrenewable natural resources. Accessibility of villages did not influence household income and livelihood activities, and poorer households were not found to depend more on natural resources or on income from agriculture than wealthier households. The option of gold prospecting constitutes a major difference compared to more nontimber forest product-based livelihoods in adjacent areas of Southwest China.