Origin of Mountain Passes across Continental Divide Segments Surrounding the Southwest Montana Big Hole and Beaverhead River Drainage Basins, USA

The evolution of southwest Montana’s Big Hole and Beaverhead River drainage basins is determined from topographic map evidence related to mountain passes crossing what are today high altitude drainage divides including North America’s east-west Continental Divide. Map evidence, such as orientations of valleys leading away from mountain passes (and saddles) and barbed tributaries found along the downstream drainage routes, is used to reconstruct flow directions of streams and rivers that once crossed the present-day high mountain divides. Large south-oriented anastomosing complexes of diverging and converging channels are interpreted to have eroded what are today closely spaced passes and saddles now notched into high mountain ridges. Water in those south-oriented channels is interpreted to have flowed across emerging mountains and subsiding basins. Headward erosion of deeper southeast-oriented valleys, assisted by crustal warping, concentrated south-oriented water in fewer and deeper valleys as the water flowed from southwest Montana into what are today Idaho and the Snake River drainage basin. Headward erosion of the Big Hole River valley between the emerging Anaconda and Pioneer Mountains, also assisted by crustal warping, reversed all Big Hole Basin drainage so as to create the north-, east-, and south-oriented Big Hole River drainage route. A final and even more major reversal of flow in the present-day north-oriented Montana Missouri River valley, with the assistance of additional crustal warping, next ended all remaining flow to Idaho and the Snake River drainage basin and reversed and captured all drainage in the present-day north-oriented Big Hole, Beaverhead, and Red Rock River drainage basins. The observed map evidence indicates that prior to the final flow reversal events, large volumes of south-oriented water flowed across southwest Montana’s Big Hole and Beaverhead River drainage basins.

Geochemical Characteristics and Origin of Natural Gases in the Qaidam Basin,China

Sixty-five natural gas samples were collected from 19 oil-gasfields in theQaidam basin, China. The chemical composition and carbon isotope values of the samples weremeasured, and the geochemical characteristics and origin of the natural gases were studied. Thegases can be divided into biogenic gases, sapropelic oil-type gases, mixed type oil-type gases,coal-type gases and mixed gas. The delta^(13)C_1 values of the biogenic gases are very small and theC_2^+ contents of them are very low, ranging from -68.2 per thousand to -61 .8 per thousand and0.06 percent to 0.20 percent respectively. They have heavy delta D and delta^(13)C_(CO_2), showing aCO_2 reduction pathway. They ,are distributed in the East depression region and derived from theQuaternary source rocks. The sapropelic oil-type gases have small delta^(13)C_2 values and highC_2^+ ranging from -36.6 per thousand to -28.6 per thousand and from 33.01 percent to 47.15 percentrespectively. The mixed type oil-type gases have delta^(13)C_2 values and C_2^+ contents varyingfrom -28.6 per thousand to -24.8 per thousand and from 4.81 percent to 26.06 percent respectively.Both sapropelic oil-type gases and mixed type oil-type gases are associated with oil-type oils,distributed in the West depression region and derived from the Tertiary saltwater lacustrinesapropelic source rocks and humic source rocks respectively. The delta^(13)C_2 values of thecoal-type gases are extremely high and the C_2^+ contents are very low, changing from -23.3 perthousand to -12.5 per thousand and from 0.06 percent to 18.07 percent respectively. The coal-typegases in the Nanbaxian gasfield and the Lenghu oil-gasfields in the North fault block belt arederived from the Middle Jurassic coal-measures source rocks, whereas those in the West depressionregion are derived from the Tertiary saltwater lacustrine humic source rocks. Compared with someother basins in China, the natural gases there have obviously heavier delta^(13)C due to the heavierdelta^(13)C of different types of kerogens of the Tertiary saltwater lacustrine source rocks in theWest depression region of the basin. The mixing of natural gases is common in the West depressionregion, but the mixed gases are formed by sapropelic oil-type gases, mixed type oil-type gases orcoal-type gases, respectively, of different levels of maturity. Most of the sapropelic oil-typegases and mixed type oil-type gases in the west part are thermally immature and low-mature, but thecoal-type gases in the West depression region and the North fault block belt are mature and high- toover-mature.

Origin and Distribution of Hydrogen Sulfide in Oil-Bearing Basins,China

The concentration of hydrogen sulfide gas （H2S） varies greatly in the oil-bearing basins of China, from zero to 90%. At present, oil and gas reservoirs with high H2S concentration have been discovered in three basins, viz. the Bohai Bay Basin, Sichuan Basin and the Tarim Basin, whereas natural gas with low H2S concentration has been found in the Ordos Basin, the Songliao Basin and the Junggar Basin. Studies suggest that in China H2S origin types are very complex. In the carbonate reservoir of the Sichuan Basin, the Ordos Basin and the Tarim Basin, as well as the carbonatedominated reservoir in the Luojia area of the Jiyang depression in the Bohai Bay Basin, Wumaying areas of the Huanghua depression, and Zhaolanzhuang areas of the Jizhong depression, the H2S is of Thermochemical Sulfate Reduction （TSR） origin. The H2S is of Bacterial Sulphate Reduction （BSR） origin deduced from the waterflooding operation in the Changheng Oilfield （placanticline oil fields） in the Songliao Basin. H2S originates from thermal decomposition of sulfur-bearing crude oil in the heavy oil area in the Junggar Basin and in the Liaohe heavy oil steam pilot area in the western depression of the Bohai Bay Basin. The origin types are most complex, including TSR and thermal decomposition of sulfcompounds among other combinations of causes. Various methods have been tried to identify the origin mechanism and to predict the distribution of H2S. The origin identification methods for H2S mainly comprise sulfur and carbon isotopes, reservoir petrology, particular biomarkers, and petroleum geology integrated technologies; using a combination of these applications can allow the accurate identification of the origins of H2S. The prediction technologies for primary and secondary origin of H2S have been set up separately.

Geochemistry of Heavy Oil in the T Block,Oriente Basin and its Origin Mechanism

Exploration and development experience show that there is obvious oil gravity difference between the southern part and northern part of the ＂M1＂reservoir in the Fanny oil field in the slope of the Oriente Basin, Ecuador. The American Petroleum Institute Gravity （API） values of oils in the northern part are higher than the one in the southern part of the Fanny oil field, with the values of 20° and 10.0°-13.0°, respectively. So the primary purpose of this study was to analyze the heavy oil characteristics of biodegradation and the oil-oil correlation according to the biomarker data and the δ^13C signature of oil samples from T block. The results of the hydrocarbon gas chromatography fingermark and the inversion attribute characteristics indicated that there are fluid compartments between the ＂M1＂ reservoir of Fanny south. Finally, the models of oil-gas accumulation under the control of multiple-activities of complicated fault systems, as well as the origin of heavy oil, are contended. The early stage oils from the western part of the basin were biodegraded heavily in varying degrees in the whole basin, and the later stage oils were derived from the southern part in a large scale and were mature and lighter. Generally, oil mixing is the primary control of net oil properties, such as API gravity in Oriente Basin. We therefore predicted that the API gravity variation of oil pools radically depends on the injection amount of the later stage oil. Because of the shale barrier in the ＂M1＂reservoir of Fanny south, the later stage hydrocarbon could not pass through and contribute to increase the oil API value.

The Original Organism Assemblages and Kerogen Carbon Isotopic Compositions of the Early Paleozoic Source Rocks in the Tarim Basin, China

Original organisms are the biological precursors of organic matter in source rocks. Original organisms in source rocks are informative for oil-source rock correlation and hydrocarbon potential evaluation, especially for source rocks which have high-over level of thermal maturity. Systematic identification of original organism assemblages of the Lower Paleozoic potential source rocks and detailed carbon isotopic composition of kerogen analyses were conducted for four outcrop sections in the Tarim basin. Results indicated that the original organism assemblages of the lower part of the Lower Cambrian were composed mainly of benthic algae, whereas those of the Upper Cambrian and the Ordovician were characterized by planktonic algae. Kerogen carbon isotopic data demonstrated that the δ13 Ckerogen values of source rocks dominated by benthic algae are lower than-34‰, whereas the δ13 Ckerogen values of source rocks dominated by planktonic algae are higher than-30‰ in general. We tentatively suggested that the carbon species those are utilized by algae and the carbon isotopic fractionation during photosynthesis are the major controls for the δ13 Ckerogen values in the Lower Paleozoic source rocks in the Tarim basin. Correlating the δ13 C values of oils exploited in the Tarim basin, the original organism assemblages, and δ13 Ckerogen values of source rocks, it implied that the Lower Paleozoic oils exploited in the Tarim basin should be sourced from the source rocks with original organism assemblages dominated by planktonic algae, and the hydrocarbon sourced from the Cambrian benthic algae should be of great exploration potential in future. Original organism assemblages in source rocks can provide important clues for oil-source rocks correlation, especially for the source rocks with high thermal maturity.

Isotopic evidence for the moisture origin and influencing factors at Urumqi Glacier No.1 in upstream Urumqi River Basin, eastern Tianshan Mountains

The stable isotope has been extensively applied as an effective tracer especially in precipitation. In glacierized area of arid northwest China, temperature is widely considered to be a major factor affecting isotopes in precipitation, while the influences of precipitation amount, relative humidity and other meteorological parameters are still not clear. Based on analyses on stable isotope values of water samples and NCEP/NCAR(National Centers of Environmental Prediction/National Center for Atmospheric Research, USA) re-analysis data, the moisture source and characteristics of isotopes in the precipitation, meltwater and river water isotopes at Urumqi Glacier No.1 of the upstream Urumqi River Basin, eastern Tianshan Mountains from spring to autumn during four years(from 2008 to 2011) was studied. Results indicated that meltwater are the main source of water for the upper Urumqi River. Seasonal variation of δ18 O in precipitation demonstrated that δ18 O was more enriched in summer and depleted in spring and autumn. Temperature was positively correlated with isotopes, while precipitation amount and relative humidity was negatively correlated with isotopes. The water vapor was affected by westerly air mass and regional water vapor cycle. Meanwhile, back trajectory clustering analyses showed that the moisture mainly from Europe and central Asia. The moisture was more likely to be locally sourced with the ratio was 46.8%~52.1%.

Geochemical Constraints on the Origin and Evolution of Spring Waters in the Changdu-Lanping-Simao Basin, Southwestern China

Chemical and isotopic data were measured for 51 leached brine springs in the Changdu-Lanping-Simao Basin(CD-LP-SM),China.The predominance of Cl and Na,saturation indices of carbonate minerals,and Na/Cl and Ca/SO4 ratios of^1 suggest that halite,sulphate,and carbonate are the solute sources.Integration of geochemical,δ18 O,andδD values suggests that springs are mainly derived from meteoric water,ice-snow melt,and water-rock interactions.B concentrations range from 0.18 to 11.9 mg/L,withδ11 B values of-4.37‰to+32.39‰,indicating a terrestrial source.Theδ11 B-B relationships suggest B sources of crustal origin(marine carbonates with minor crust-derived volcanics);we did not identify a marine or deep mantle origin.Theδ11 B values of saline springs(+4.61‰to+32.39‰)exceed those of hot(-4.37‰to+4.53‰)and cold(-3.47‰to+14.84‰)springs;this has contributed to strong water-rock interactions and strong saturation of dissolved carbonates.Conversely,the global geothermalδ11 B-Cl/B relationship suggests mixing of marine and non-marine sources.Theδ11 B-Cl/B relationships of the CD-LP-SM are similar to those of the Tibet geothermal belt and the Nangqen Basin,indicating the same B origin.These differ from thermal waters controlled by magmatic fluids and seawater,suggesting that B in CD-LP-SM springs has a crustal origin.

Molecular Geochemical Evidence for the Origin of Natural Gas from Dissolved Hydrocarbon in Ordovician Formation Waters in Central Ordos Basin

Having studied the biomarker composition and maturity of dissolved hydrocarbons from Ordovician formation waters, the authors presented molecular geochemical evidence for the controversial origin of natural gases in central Ordos Basin.The dissolved hydrocarbons in Well Shan 12 and Well Shan 78 are relatively high in abundance of tricylic terpane, pregnane series and dibenzothiophene series and low in Pr/Ph and hopane/sterane ratios, indicating the source input of marine carbonates. In contrast, the dissolved hydrocarbons in Well Shan 81 are free from tricyclic terpane and pregnane series, with trace dibenzothiophene series and high Pr/Ph and higher hopane/sterane ratios, which are the typical features of terrestrial organic matter. Furthermore, Well Shan 37 and Well Shan 34 are between the two situations, having a mixed source of marine carbonate and terrestrial organic matter. The maturity of biomarkers also supports the above suggestions. These results are consistent with the geological background and source rock distribution in this region.

Origin of CO_2 gas from the north depression of the middle fault zone in the Hailar-Tamtsag Basin and natural gas in nearby depressions

Natural gas pools with the high contents of CO2 were discovered during exploring the middle fault zone of the Hailar-Tamtsag Basin. So far this kind of gas reservoir with CO2 with characteristics of carbon isotope is spe-cial. The stable carbon isotope of CO2 in the study area is relatively light with δ13 CCO2 values ranging from -13.1‰ to -8.2‰. The 40Ar/36Ar values of associated argon gas range from 916 to 996, with R/Ra of 1.20-1.26. Based on comprehensive analysis, it is believed that the CO2 gas in this study area is of crust mantle source.

Origin and Distribution of Grain Dolostone Reservoirs in the Cambrian Longwangmiao Formation,Sichuan Basin,China

Dolostones in the Cambrian Longwangmiao Formation have become one of the most significant gas exploration domains in China. Over a trillion cubic meters of gas reservoirs have been discovered in the Gaoshiti-Moxi area; however, the origins and distribution of the dolostone reservoirs are not well understood. This work discussed the geology and geochemistry of the dolostone reservoirs in the Longwangmiao Formation to determine their origin and distribution. Two understandings are acquired： firstly, a carbonate ramp provided excellent conditions for grain beach deposition, while the presence of a hypersaline lake was favorable for the contemporaneous dolomitization of grain beach deposits. Petrographic and geochemical evidence further confirm that the Longwangmiao dolostone was formed during the contemporaneous stage. Secondly, the reservoir characteristics indicate that the grain beach sediments provide material basis for the development of the Longwangmiao dolostone reservoirs. Reservoir dissolution simulation experiments show that the porosity of the reservoirs was formed by dissolution during contemporaneous and burial stages. The dissolution pores formed during the contemporaneous stage were controlled by sequence interfaces. The large scale dissolution vugs formed during the burial stage subsequently spread along the pre-existing porosity and fracture zones. This study therefore identified that the development of grain dolostone reservoirs in a shallow water ramp under arid climatic conditions generally met the following conditions：（1） reefal beach deposits lay a foundation for reservoir development;（2） superficial conditions are an important determining factor for reservoir porosity; and（3） burial conditions provide environment for porosity preservation and modification.

Characteristics and Origin of Yacheng Gas Field in Qiongdongnan Basin,South China Sea

The Yacheng gas field lies in the foot wall of the No. 1 fault, the boundary fault between the Yinggehai and Qiongdongnan basins. An overpressured system developed in the Meishan Formation near the No. 1 fault in the gas field and in the adjacent Yinggehai basin. Away from this fault into the Qiongdongnan basin, the overpressure diminishes. Below 3 600 m in the gas field, an obvious thermal anomaly occurs. The gases show obvious compositional heterogeneities which reflect reservoir filling process and origin of the gas field. The gas field was charged from both the Qiongdongnan and the Yinggehai basins but mainly from the former. Hydrocarbons sourced from the Qiongdongnan basin have relatively low maturities while hydrocarbons from the Yinggehai basin have relatively high maturities.

Origin and evolution of oilfield brines from Tertiary strata in western Qaidam Basin:Constraints from ^(87)Sr/^(86)Sr,δD,δ^(18)O,δ^(34)S and water chemistry

Chemistry of major and minor elements,87Sr/86Sr,δD,δ18O and δ34S of brines were measured from Tertiary strata and Quaternary salt lakes in the western Qaidam Basin.The water chemistry data show that all oilfield brines are CaCl2 type.They were enriched in Ca2+,B3+,Li+,Sr2+,Br-,and were depleted in Mg2+,SO42-,which indicated that these brines had the characteristics of deeply circulated water.The relationship between δD and δ18O shows that all data of these brines decline towards the Global Meteoric Water Line(GWL) and Qaidam Meteoric Water Line(QWL),and that the intersection between oilfield brines and Meteoric Water Lines was close to the local spring and fresh water in the piedmont in the western Qaidam Basin.The results suggest that oilfield brines has initially originated from meteoric water,and then might be affected by water-rock metamorphose,because most oilfield brines distribute in the range of metamorphosing water.The 87Sr/86Sr values of most oilfield brines range from 0.71121 to 0.71194,and was less than that in salt lake water(>0.712),but close to that of halite in the study area.These imply that salt dissolution occurred in the process of migration.In addition,all oilfield brines have obviously much positive δ34S values(ranging from 26.46‰ to 54.57‰) than that of salt lake brines,which was caused by bacterial sulfate reduction resulting in positive shift of δ34S value and depleteed SO42-in oilfield brines.Combined with water chemical data and δD,δ18O,87Sr/86Sr,δ34S values,we concluded that oilfield brines mainly originate from the deeply circulated meteoric waters,and then are affected by salt dissolution,water-rock metamorphose,sulfate reduction and dolomitization during the process of migration.These processes alter the chemical compositions of oilfield brines and accumulate rich elements(such as B,Li,Sr,Br,K and so on) for sustainable utilization of salt lake resources in the Qaidam Basin.

柴达木盆地周缘沉积锰矿带:一个极具资源潜力的锰矿集中区

近年来在阿尔金、祁连山和东昆仑地区的沉积型锰矿找矿工作取得了突破性进展。从空间分布特征看,这些锰矿均沿柴达木盆地周缘展布。前人曾针对单个矿床地质特征进行过研究,但对于柴达木盆地周缘的锰矿为什么主要形成于中—新元古代至早古生代、锰矿与柴达木地块及周缘造山带演化之间的关系等尚缺少深入的研究与总结。本文从东昆仑、阿尔金、祁连山等环柴达木盆地周缘造山带的角度,分析了沉积锰矿床地质特征和产出规律,重塑了原特提斯洋在青藏东北部的演化过程,为深入理解原特提斯构造演化与沉积锰矿成矿作用的关系提供证据。

Composition and Origin of Shallow Biogenetic Gases in the Baise Basin, South China

Based on the analytical data of over 30 gas samples, combined with geochemical and geological backgrounds, the composition and distribution characteristics of shallow biogenetic gases in the Baise Basin, a Tertiary residual basin in southern China, were extensively investigated, and the origin and formation mechanism tentatively approached. The shallow gases are primarily composed of gaseous hydrocarbons, generally accounting for over 90%. The abundances of methane and C2＋ homologues show a relatively wide range of variation, mainly 50%-100% and 0%-50%, respectively, depending on the mixing proportions between biogenetic and thermogenic gases. A highly negative carbon isotope is the significant signature for the shallow gases with δ^13C1 values of -55‰ to -75‰. According to molecular and isotopic compositions and light hydrocarbon parameters, the shallow gases in the basin can be classified into three types of origins： biogenetic gas, biogenetic/thermogenic mixed gas, and oii-biodegraded gas. They exhibit regular distribution both spatially and temporally, and are believed to be associated with the maturity of adjoining gas source rocks and biodegraded oil accumulation. The Baigang and Nadu source rocks can be considered to have experienced early and late gas generation during early burial and after basin uplift respectively. A late accumulation mechanism of multiple gas sources is put forward for the formation of the shallow gas reservoirs, which is responsible for the variations in chemical and isotopic composition of the gases in depth profile.

兰州不同城镇功能区地下水氟赋存特征及影响因素

高氟地下水对生态环境及人类健康存在潜在威胁。城镇化地区受地质背景与人类活动双重影响,地下水中氟的来源及其分布较为复杂,探讨地下水中氟的赋存特征对于保障地下水供水安全具有重要意义。以西北干旱区最大的工业城市兰州为例,采用数理统计、离子比、饱和指数分析等方法,研究了兰州不同城镇功能区高氟地下水的赋存环境特征及主要水文地球化学过程,阐明了人为活动对氟化物迁移富集的影响。结果表明:(1)研究区地下水中F-的质量浓度介于0~4.8mg/L之间,超出地下水质量Ⅲ类标准(1.0mg/L)的高氟水共计13组,超标率为20.3%。(2)受人类活动强度与不同人为源输入影响,不同城镇功能区地下水中氟的赋存特征差异明显,其中西固工业区地下水中氟含量最高,高氟地下水样品占47.4%;城关老城区和断陷盆地新城区地下水中的氟含量相对较低,高氟地下水占比依次为7.1%和9.7%。(3)研究区高氟地下水以SO_(4)•Cl—Na和Cl•SO_(4)—Na型水为主,表现出贫钙富钠弱碱性特点。(4)含氟矿物的溶解、方解石与白云石的沉淀/溶解、黏土矿物表面钙与钠之间的阳离子交换、强烈的蒸发浓缩作用和盐效应是导致研究区地下水中氟化物富集的主要水文地球化学过程。研究表明城镇化、工业化导致天然高氟水进一步劣变恶化,工业废水的泄漏是西固工业区地下水氟浓度升高的重要驱动力。结果可为高氟背景区人为干扰下的氟化物迁移富集研究提供借鉴。

豫西黄河流域古地名源流及其文化内核

豫西黄河流域既是一个地理概念,也是一个文化范畴。在这一区域,黄河及其支流的自然山水、人文因素,催生了不少古地名。丰厚的历史文化积淀,使这一区域的地名源头,从遥远的上古时期延续到漫长的奴隶社会、封建社会乃至近代。地名作为历史的活化石,记载着这一区域的朝代更迭、历史变迁,记载着风云人物、风物传奇,也同样记载着民间百姓的生活和生存状态。豫西黄河流域古地名丰富的历史文化底蕴,主要生发于该区域文化内核——仰韶文化、殷商文化、秦汉文化、唐宋文化等,也得益于黄河这一华夏文明的摇篮。

鄂尔多斯盆地奥陶系盐下储层中固体沥青的发现及其对天然气成藏的启示

近期,鄂尔多斯盆地奥陶系盐下地层取得了天然气重大勘探突破和新进展,已成为天然气勘探的重点新领域。但是,该领域天然气成因、资源潜力等关键成藏问题尚不清楚。为此,以鄂尔多斯盆地中东部奥陶系马家沟组五段7亚段—马家沟组四段(以下简称马五7亚段—马四段)为研究对象,通过岩心与显微镜观察,发现盐下储层中存在固体沥青,并明确了沥青的产状和地球化学特征,最后结合天然气地球化学分析,探讨了盐下地层中天然气(以下简称盐下天然气)的成因和资源潜力。研究结果表明:(1)奥陶系盐下储层中存在大量固体沥青,透射光显微镜观察沥青呈花状、片状、团块状、薄膜状或条带状赋存于白云岩和石灰岩的孔、缝、缝合线和沥青包裹体内,固体沥青的质量百分数介于0.07%~0.55%(平均值为0.17%),等效镜质体反射率介于1.75%~1.97%,碳同位素值介于-28.4‰~-27.7‰;(2)盐下天然气干燥系数介于0.95~1.00,为典型的干气,天然气的甲烷、乙烷和丙烷碳同位素值分别介于-44.8‰~-32.4‰、-31.1‰~-22.6‰和-28.8‰~-19.7‰,具有甲烷碳同位素偏轻、乙烷与丙烷碳同位素偏重的异常特征;(3)奥陶系盐下储层中的固体沥青和天然气均为石油热裂解成因,石油来自于马家沟组或更古老的地层,石油裂解发生在早白垩世中—晚期;(4)盐下天然气遭受了不同程度的硫酸盐热化学还原作用的改造,其中乌审旗地区改造程度较强,天然气中H2S含量高,最高可达13.31%。结论认为,马五7亚段—马四段天然气预测储量约为1.00×1012 m3,该盆地奥陶系盐下天然气勘探潜力巨大。

鄂尔多斯盆地中东部奥陶系盐下层系白云岩储层沉积特征及发育演化机理

鄂尔多斯盆地马家沟组盐下的碳酸盐岩—蒸发岩层系是未来油气勘探的重要接替层系。由于碳酸盐岩—蒸发岩的特殊沉积组合强烈影响后续差异化成岩流体溶蚀—充填作用,进一步增大了盐下碳酸盐岩储层的复杂性,也给优质储层的分布预测增加了难度。本文以鄂尔多斯盆地马家沟组中下组合为研究对象,基于岩心、薄片、物性资料等开展储层地质学研究,识别出15种岩石类型和10类相序组合,明确了盐下储层类型包括:膏模孔泥晶云岩储层、颗粒白云岩储层、斑状白云岩储层、晶粒白云岩储层和微生物白云岩储层。在孔隙成因和演化分析基础上,建立了“优势沉积相+早期成孔+膏盐岩封盖保存孔隙”的盐下白云岩储层发育地质模式。研究结果深化了对盐下碳酸盐岩层系孔隙形成和保存机理的认识,同时对鄂尔多斯盆地的油气资源勘探开发具有重要的现实意义。

柴达木盆地东缘德令哈柏树山大型天然饮用矿泉水成因分析

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