To estimate the volume of oil and gas in the hydrocarbon reservoirs, the rock-typing must be considered. The volume and type of available space in the reservoir rocks (porosity) and the ease of hydrocarbons flow (perm...To estimate the volume of oil and gas in the hydrocarbon reservoirs, the rock-typing must be considered. The volume and type of available space in the reservoir rocks (porosity) and the ease of hydrocarbons flow (permeability) are important in the classification of rock-types. In the field study, touching-vug Porosities (intergranular, intercrystalline and brecciate) increase the total porosity and form high quality rock-types, on the other side, separated-vug porosities (such as moldic, intraparticle and vuggy) increase the total porosity but do not play a large role in the production of hydrocarbon. In this paper, based on the SCAL data (Special Core Analysis) and according to amount of irreducible water saturation (Swir) and capillary pressure, the reservoir rocks are divided into 4 classes including Reservoir Rock-Types 1 to Reservoir Rock-Types 4 (RRTs-1 to RRTs-4). By study of the prepared thin sections, we investigated the role of porosity in the rock-typing. Among the rock-types, category 1 is the best type-reservoir and category 4 is non-reservoir. Probably, the latest diagenetic process determines the quality rocks, not sedimentary environments.展开更多
Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,20...Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,2018).It is an important part of the Central Orogenic Belt(Xiong et al.,2023).It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al.,2023)and an essential potential base for mineral resources in China.Wulonggou and Gouli gold mines have been discovered successively,earning the reputation of the"Golden Belt of Qinghai Province"(Feng et al.,2004;He et al.,2023).展开更多
Gold deposits occurring in the Liaodong rift are located in interlayered carbonate rocks and fine-clastic rocks, belonging to the middle and upper parts of the lower Proterozoic. Compared with the Carlin-type Au depos...Gold deposits occurring in the Liaodong rift are located in interlayered carbonate rocks and fine-clastic rocks, belonging to the middle and upper parts of the lower Proterozoic. Compared with the Carlin-type Au deposits abroad and gold deposits in Yunnan-Guizhou-Guangxi, Qinling and western Sichuan Province, they are similar in many respects. This paper discusses the geological features of ore-bearing formations and ore-filling structures and metallogenetic characteristics. Through the discussion on the sources of ores, heat and water, it points out that the Au deposits belong to vadose reworked hydrothermal deposits. This conforms to the principle of “mineralization in the neighbouring areas”, i.e., the deposits are formed in nearby ore-bearing layers, and the latest hydrothermal event was the main factor in forming the Au deposits.展开更多
文摘To estimate the volume of oil and gas in the hydrocarbon reservoirs, the rock-typing must be considered. The volume and type of available space in the reservoir rocks (porosity) and the ease of hydrocarbons flow (permeability) are important in the classification of rock-types. In the field study, touching-vug Porosities (intergranular, intercrystalline and brecciate) increase the total porosity and form high quality rock-types, on the other side, separated-vug porosities (such as moldic, intraparticle and vuggy) increase the total porosity but do not play a large role in the production of hydrocarbon. In this paper, based on the SCAL data (Special Core Analysis) and according to amount of irreducible water saturation (Swir) and capillary pressure, the reservoir rocks are divided into 4 classes including Reservoir Rock-Types 1 to Reservoir Rock-Types 4 (RRTs-1 to RRTs-4). By study of the prepared thin sections, we investigated the role of porosity in the rock-typing. Among the rock-types, category 1 is the best type-reservoir and category 4 is non-reservoir. Probably, the latest diagenetic process determines the quality rocks, not sedimentary environments.
基金supported by Qinghai Provincial Association for Science and Technology Youth Science and Technology Talent Support Project(Grant No.2023QHSKXRCTJ47)Exploration Foundation of Qinghai Province(Grant No.2023085029ky004)。
文摘Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,2018).It is an important part of the Central Orogenic Belt(Xiong et al.,2023).It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al.,2023)and an essential potential base for mineral resources in China.Wulonggou and Gouli gold mines have been discovered successively,earning the reputation of the"Golden Belt of Qinghai Province"(Feng et al.,2004;He et al.,2023).
文摘Gold deposits occurring in the Liaodong rift are located in interlayered carbonate rocks and fine-clastic rocks, belonging to the middle and upper parts of the lower Proterozoic. Compared with the Carlin-type Au deposits abroad and gold deposits in Yunnan-Guizhou-Guangxi, Qinling and western Sichuan Province, they are similar in many respects. This paper discusses the geological features of ore-bearing formations and ore-filling structures and metallogenetic characteristics. Through the discussion on the sources of ores, heat and water, it points out that the Au deposits belong to vadose reworked hydrothermal deposits. This conforms to the principle of “mineralization in the neighbouring areas”, i.e., the deposits are formed in nearby ore-bearing layers, and the latest hydrothermal event was the main factor in forming the Au deposits.