Mud volcanism and fluid geochemistry in the Cheleken peninsula,western Turkmenistan

A geological and geochemical study has been carried out to investigate the relationships between major mud volcano structures and deep fluid migration in the Cheleken peninsula, in the South Caspian Basin. The fluid geochemistry allowed the origin and migration of the saline waters and the hydrocarbons to be deduced along with the regional source and reservoir rocks. The emitted waters formed by the mixing of deep highly saline water from the main source rocks of the Maykop Fm with the Caspian-like pore water contained in the Pliocene reservoirs. The water composition is very similar to that emitted by the mud volcanoes in Azerbaijan, allowing comparisons to be done between the reservoirs in the western and eastern sides of the South Caspian Basin. The associated oil is derived from a mixed type II/III kerogen deposited in a sub-oxic marine environment and generated during the early oil window. The oil biomarkers indicate that the source rock is the Maykop Fm., as previously determined for the other areas of the South Caspian Basin.The spontaneous emissions, showing different morphologies, are mainly aligned along normal and transtensive fault systems, which provide effective pathways for rapid fluid ascent from deep reservoirs to the surface.     

土库曼斯坦阿姆河盆地卡洛夫-牛津阶储层特征及控制因素分析

土库曼斯坦东北部的阿姆河盆地,是中亚地区最重要的含油气盆地之一。根据钻井岩芯和分析化验资料,确定阿姆河盆地卡洛夫-牛津阶为碳酸盐台地相沉积,具有特征的前缘缓斜坡沉积模式,可划分为蒸发台地、局限台地、开阔台地、台地边缘、前缘缓斜坡和盆地6个相带。其中台内、台地边缘和前缘缓斜坡为储层发育相带,尤以发育于台地边缘、开阔台地和前缘缓斜坡相带中的礁、滩微相最有利于储层发育。沉积微相和岩性对储层类型及物性有直接控制,特点为高能环境条件下沉积的块状礁灰岩和中-厚层状滩相颗粒灰岩以发育原生孔隙保存良好的孔隙型和裂缝-孔隙型储层为主,而较低能环境条件下沉积的(含)颗粒微晶灰岩、隐藻灰岩和泥-微晶灰岩以发育基质岩物性很差的裂缝型储层为主。通过综合分析,认为储层发育受沉积微相、岩性和成岩作用复合控制,以各相带内的礁、滩微相灰岩为高效勘探开发目标的"甜心"位置。     

Origin and Distribution Factors of Sour Gases in Natural Gas Reservoirs in the Amu Darya Right Bank Block,Turkmenistan

Through the analysis of original carbon isotopes in the blocks on the right bank of the Amu Darya River, Turkmenistan, it can be firstly concluded that the carbon dioxide (CO₂) in the sour gas reservoirs belongs to the inorganic-origin gas. The origin of hydrogen sulfide (H₂S) in the Amu Darya Right Bank Block is thermochemical sulfate reduction from the detailed analysis of hydrocarbon source rocks data, reservoir characteristics, vitrinite reflectance of organic matter, and sour gas content. Then, the factors affecting the distribution of sour gases in the Amu Darya Right Bank Block were investigated by the analysis of conventional sour gas distribution factors including geological structure, fracture and fault, caprock integrity, sedimentary facies, reservoir types, lithofacies, the source of sulfur and so on. The following basic findings were achieved: ① The basement rift in the study area is conductive to the distribution of CO₂. The caprock integrity contributes to the concentration of CO₂. The gas reservoirs in the biological dike reefs, patch reefs and overthrust zones usually have medium CO₂ content. ② The geological structure and fracture caused the complexity of the distribution of H₂S. The gypsum-salt rock in upper Jurassic-Tithonian is an important sulphur source, and the main hydrocarbon source rocks are also the major sulfur source of H₂S gas reservoirs. Furthermore, the giant gypsum layers in the middle-upper Jurassic Callovian-Oxfordian and the upper Jurassic-Tithonian are conductive to preservation of H₂S, and the small openings and holes in the reservoir is also correlative to the distribution of H₂S. ③ The H₂S in the study area is mostly distributed in the formations with the geothermal temperature of higher than 100 ℃. The open platform deep-water sedimentary facies are harmful to the formation of H₂S. The patch reef and overthrust zones belong to the belts of low H₂S content, however, the biological dike reef zones belong to the belts of medium-high H₂S content. However, the origin and distribution factors of sour gases in natural gas reservoirs were obtained. At the same time, it was pointed out that more necessary and accurately quantitative research is still needed to determine the origin and distribution of acid gases in the Amu Darya Right Bank Block, Turkmenistan.     

成像测井在台缘斜坡礁滩微相研究中的应用——以土库曼斯坦阿姆河右岸中部卡洛夫阶—牛津阶为例

以成像测井资料为基础,开展了土库曼斯坦阿姆河右岸中部的中上侏罗统卡洛夫阶—牛津阶台缘斜坡礁滩沉积微相研究。首先利用岩心、薄片等资料对成像测井进行标定,在成像测井上识别出障积礁、粘结丘、高能生物碎屑滩、低能生物碎屑滩、低能砂屑滩、礁(滩)间和斜坡泥等7种沉积微相。然后通过对不同类型沉积微相的成像测井响应特征进行研究,建立了研究区碳酸盐岩成像测井相模式,主要包括亮斑相、暗斑相、低阻交错层状相、低阻变形层状相、互层相、块状相等6类,并以此为依据进行了连续的单井成像测井相划分与沉积微相解释。最后对沉积微相与储层物性关系进行了研究,认为研究区卡洛夫阶—牛津阶储层主要为裂缝-孔隙型礁滩储层,有利于储层发育的沉积微相主要为高能生物碎屑滩、低能砂屑滩、障积礁、低能生物碎屑滩和粘结丘,礁(滩)间和斜坡泥微相的岩性相对较致密,储层一般不发育。     

土库曼斯坦物种多样性及其与中国新疆的比较

土库曼斯坦与中国新疆在地理地形、景观带以及气候特征等诸多方面具有相似之处,这些因素共同决定了二者在物种多样性方面的相似性与可比性,加之人类活动影响加剧,两地物种多样性均遭受着严重的威胁。在对土库曼斯坦和中国新疆现有物种多样性数据进行总结的基础上,分析了二者的物种多样性现状、珍稀动植物特征以及濒危种和入侵种相关研究进展,对比了二者在物种多样性年际尺度上的异同,总结了土库曼斯坦与中国新疆物种多样性保护现状与相关政策,以期为深入开展两地生物多样性合作与交流提供支持。     

Facies analysis of the Callovian–Oxfordian carbonates in the northeastern Amu Darya Basin,southeastern Turkmenistan

The Callovian–Oxfordian carbonates in the northeastern Amu Darya Basin of southeastern Turkmenistan, are composed of medium-to thick-bedded, mostly grainy limestones with various skeletal (bivalves, brachiopods, echinoderms, foraminifera, corals, and sponge) and non-skeletal grains (intraclasts, ooids, and peloids). The 6 microfacies types recognized in the Callovianand and 18 microfacies types in Oxfordian carbonates are grouped into two depositional phases, ramp and platform. The Callovian carbonates were deposited on a carbonate ramp, which evolved into a depositional platform in the Oxfordian. The main components of the Oxfordian platform margin complex are reefs and shoals. The principal reef builders are corals, algae and sponges. Regional tectonic movements, eustatic sea-level changes and sedimentation rates were the primary controlling factors of facies evolution during the Callovian–Oxfordian time in the northeastern Amu Darya Basin.     

How far between Iran and Eurasia was the Turan plate during Triassic–Jurassic times?

Calc-alkaline volcanic deposits from the south-west of the Turan plate, near the city of Turkmenbasi (40°00N, 52°58&\prime;E) in Turkmenistan, were studied paleomagnetically. These rocks have been affected by a greenschist-facies metamorphism, possibly of regional extent, that has been K/Ar-dated as 200 to 227 Ma old. A low-blocking-temperature component (D = 349°, I = 64°), close to the present field direction and probably of viscous or recent chemical origin, was isolated by a negative fold test at three sites. The mean direction of a high-blocking-temperature component isolated at 15 sites, mainly carried by magnetite, is scattered before and after tectonic correction and is therefore difficult to interpret. A group of seven sites with low inclinations before and after tectonic correction was isolated. The mean inclination of these sites (31 ± 8°), syn-folding or post-folding, corresponds to a paleolatitude of 17 ± 8° which is lower than the conventional Eurasian paleolatitudes for post-Permian times. The paleomagnetic data from the Turan and Iran plates constrain this low paleolatitude to the Late Triassic and Jurassic period. This requires a shortening of at least 7° between the Turan plate and Eurasia during this time.     

土库曼斯坦萨曼杰佩气田卡洛夫-牛津阶碳酸盐岩沉积-成岩系统

以土库曼斯坦阿姆河盆地萨曼杰佩气田主力油、气产层卡洛夫-牛津阶碳酸盐岩为例,根据沉积相、成岩作用方式、成岩演化序列和相对应的地质作用产物特征,综合研究Fe、Mn、Sr微量元素,C、O、Sr稳定同位素,流体包裹体和阴极发光等地球化学特征反映的成岩环境和成岩流体性质。按"水文体制"将卡洛夫-牛津阶划分为不同成岩阶段的海水-淡水、压实卤水和深循环温压水3个成岩系统,认为沉积-成岩系统与储层在时空上具有良好的耦合关系,可归结为:台地边缘生物礁和浅滩相控制了储层的区域分布;早成岩阶段淡水系统溶蚀作用和压实卤水成岩系统的浅埋藏白云岩化作用是形成储层的基础;中成岩阶段的温压水成岩系统埋藏溶蚀作用、中-深埋藏白云石化作用和构造破裂作用扩大了储层规模,提高了储层质量,对优质储层发育贡献最大。     

土库曼斯坦萨曼杰佩气田卡洛夫-牛津阶碳酸盐岩储层特征

土库曼斯坦萨曼杰佩气田卡洛夫阶—牛津阶碳酸盐岩沉积相类型丰富,发育有台地前缘缓斜坡、台地边缘生物礁和浅滩、开阔台地和局限台地5个相带,储层岩性主要为台地边缘生物礁和浅滩相的礁灰岩、生物屑灰岩和鲕粒灰岩等,具有厚度大和大多为优质储层的特点。以岩芯观察描述和薄片鉴定为基础,综合利用地质、钻井、地震等资料,深入探讨了萨曼杰佩气田卡洛夫阶—牛津阶碳酸盐岩沉积相特征和储层类型,划分出孔洞缝型、孔隙型、裂缝-孔隙型和裂缝性储层类型,确定孔洞缝复合型储集层主要发育于高能环境下形成的台地边缘生物礁相带;孔隙型和裂缝-孔隙型储层主要发育在相对高能的台地边缘浅滩相带,在开阔台地台内浅滩中也有一定规模的发育;裂缝型储层主要分布在泻湖和潮下等低能相带。在此基础上建立了不同储层类型的测井相响应模式。研究了岩性、沉积相以及成岩作用对储集层发育的控制作用,认为高能的礁、滩相带最有利储层发育,而强烈的压实和胶结作用是破坏储层储集性能的主要因素。     

土库曼斯坦水资源现状及利用问题

土库曼斯坦地处亚洲中部干旱区西南部,沙漠广布,水资源短缺,是阿姆河等跨界河流水资源的主要消耗区,水资源利用问题及矛盾十分突出。开展该国水资源及其开发利用研究,对研究跨界河流及极度干旱区水资源可持续利用具有重要的借鉴意义。土库曼斯坦是中亚水资源总量最少的国家,河流多数跨界,出入境水量约为233×10⁸ m³,可利用水量远大于国内水资源总量,其中地表水资源总量约为9.39×10⁸ m³,地下水可开采量为5.69×10⁸ m³,而该国最主要的水利工程——卡拉库姆运河调来了阿姆河近1/3的水量,增加了灌溉面积。在水资源利用中,实际用水量的90%以上被用于农业灌溉,工业用水占7%左右,城市生活用水占2%。土库曼斯坦水资源主要靠调水工程和灌渠从界外引入,由于缺乏技术和资金支持,基础设施老化、管理混乱、水资源纷争复杂多变等水资源利用问题十分突出。在全球变化背景下,土库曼斯坦应加强在水资源的合理配置与高效利用、水资源国际合作等方面的工作,合理开发利用水资源。