This paper discusses the reservoir space in carbonate rocks in terms of types,combination features,distribution regularity,and controlling factors,based on core observations and tests of the North Truva Oilfield,Caspi...This paper discusses the reservoir space in carbonate rocks in terms of types,combination features,distribution regularity,and controlling factors,based on core observations and tests of the North Truva Oilfield,Caspian Basin.According to the reservoir space combinations,carbonate reservoirs can be divided into four types,i.e.,pore,fracture-pore,pore-cavity-fracture,and pore-cavity.Formation and distribution of these reservoirs is strongly controlled by deposition,diagenesis,and tectonism.In evaporated platform and restricted platform facies,the reservoirs are predominately affected by meteoric fresh water leaching in the supergene-para-syngenetic period and by uplifting and erosion in the late stage,making both platform facies contain all the above-mentioned four types of reservoirs,with various pores,such as dissolved cavities and dissolved fractures,or structural fractures occasionally in favorable structural locations.In open platform facies,the reservoirs deposited continuously in deeper water,in an environment of alternative high-energy shoals(where pore-fracture-type reservoirs are dominant) and low-energy shoals(where pore reservoirs are dominant).展开更多
In Wangjiatun area of the Northern Songliao Basin, reservoir space can be divided into three types: primary pore, secondary pore and fissure according to their origins,which can be subdivided into eight subtypes: macr...In Wangjiatun area of the Northern Songliao Basin, reservoir space can be divided into three types: primary pore, secondary pore and fissure according to their origins,which can be subdivided into eight subtypes: macro-vesicule, shrank primary vesicule, alteration pore, groundmass corrosive pore, normal structural crack, corrosive structural crack, filled structural crack and groundmass shrank crack according to texture and origin of the pore space. It has characteristic of double pore medium. Volcanic porosities of small diameter samples (with diameter of ca. 2.5 cm) and large diameter samples (with diameter of ca. 21.5 cm) were tested in accordance with the characteristic of volcanic reservoir space. Volcanic porosities for small diameter samples correspond with matrix porosities and those of large diameter samples correspond with total porosities including matrix and fractured porosities. Models of the calculated porosity by acoustic wave or density of volcanic reservoir are established in view of those measured data. Comparison of calculated and measuredporosities shows that precision of calculated porosities is lower for rhyolite and tuffites, and higher for basaltand andesite. Relative errors of calculated porosities by model of large diameter samples are lower than those of small diameter samples, i. e. precision of the former is higher than that of the later.展开更多
Based on digital elevation models SRTM03 and SRTM30_Plus (Shuttle Radar Topography Mission Survey) the technique for detecting major structural elements and elucidating details of the geologic structure including disc...Based on digital elevation models SRTM03 and SRTM30_Plus (Shuttle Radar Topography Mission Survey) the technique for detecting major structural elements and elucidating details of the geologic structure including discrimination of linear structures and texture features is elaborated. The computation of the modulus of the first derivative by the co- ordinate, i.展开更多
Based on the qualitative study of microscopic reservoir features using core analysis,cast and fluorescence thin sections inspection,scanning electron microscope(SEM)and field emission scanning electron microscope(FESE...Based on the qualitative study of microscopic reservoir features using core analysis,cast and fluorescence thin sections inspection,scanning electron microscope(SEM)and field emission scanning electron microscope(FESEM)and quantitative examination of pore size and geometry using mercury injection,nano-CT and nitrogen adsorption,reservoir rock of Da’anzhai Member were divided into 9 types,while storage spaces were divided into 4 types and 14 sub-types.The study shows that sparry coquina is the most promising reservoir type.Pores that smaller than 1μm in diameter contribute 91.27%of storage space volume.Most of them exhibit slot-like geometry with good connectivity.By building up storage space models,it was revealed that micron scale storage spaces mainly composed of fractures and nanometer scale pores and fractures form multi-scale dual porosity system.Low resource abundance,small single well controlled reserve,and low production are related to the nano-scale pore space in Da’anzhai Memer,whereas the dual-porosity system composed of pores and fractures makes for long-term oil yield.Due to the existence of abundant slot-like pore space and fractures,economic tight oil production was achieved without stimulations.展开更多
基金supported by the National Major Science and Technology Project (No.2016ZX05030002)
文摘This paper discusses the reservoir space in carbonate rocks in terms of types,combination features,distribution regularity,and controlling factors,based on core observations and tests of the North Truva Oilfield,Caspian Basin.According to the reservoir space combinations,carbonate reservoirs can be divided into four types,i.e.,pore,fracture-pore,pore-cavity-fracture,and pore-cavity.Formation and distribution of these reservoirs is strongly controlled by deposition,diagenesis,and tectonism.In evaporated platform and restricted platform facies,the reservoirs are predominately affected by meteoric fresh water leaching in the supergene-para-syngenetic period and by uplifting and erosion in the late stage,making both platform facies contain all the above-mentioned four types of reservoirs,with various pores,such as dissolved cavities and dissolved fractures,or structural fractures occasionally in favorable structural locations.In open platform facies,the reservoirs deposited continuously in deeper water,in an environment of alternative high-energy shoals(where pore-fracture-type reservoirs are dominant) and low-energy shoals(where pore reservoirs are dominant).
文摘In Wangjiatun area of the Northern Songliao Basin, reservoir space can be divided into three types: primary pore, secondary pore and fissure according to their origins,which can be subdivided into eight subtypes: macro-vesicule, shrank primary vesicule, alteration pore, groundmass corrosive pore, normal structural crack, corrosive structural crack, filled structural crack and groundmass shrank crack according to texture and origin of the pore space. It has characteristic of double pore medium. Volcanic porosities of small diameter samples (with diameter of ca. 2.5 cm) and large diameter samples (with diameter of ca. 21.5 cm) were tested in accordance with the characteristic of volcanic reservoir space. Volcanic porosities for small diameter samples correspond with matrix porosities and those of large diameter samples correspond with total porosities including matrix and fractured porosities. Models of the calculated porosity by acoustic wave or density of volcanic reservoir are established in view of those measured data. Comparison of calculated and measuredporosities shows that precision of calculated porosities is lower for rhyolite and tuffites, and higher for basaltand andesite. Relative errors of calculated porosities by model of large diameter samples are lower than those of small diameter samples, i. e. precision of the former is higher than that of the later.
文摘Based on digital elevation models SRTM03 and SRTM30_Plus (Shuttle Radar Topography Mission Survey) the technique for detecting major structural elements and elucidating details of the geologic structure including discrimination of linear structures and texture features is elaborated. The computation of the modulus of the first derivative by the co- ordinate, i.
基金Supported by the China National Science and Technology Major Project(2016ZX05046-001)
文摘Based on the qualitative study of microscopic reservoir features using core analysis,cast and fluorescence thin sections inspection,scanning electron microscope(SEM)and field emission scanning electron microscope(FESEM)and quantitative examination of pore size and geometry using mercury injection,nano-CT and nitrogen adsorption,reservoir rock of Da’anzhai Member were divided into 9 types,while storage spaces were divided into 4 types and 14 sub-types.The study shows that sparry coquina is the most promising reservoir type.Pores that smaller than 1μm in diameter contribute 91.27%of storage space volume.Most of them exhibit slot-like geometry with good connectivity.By building up storage space models,it was revealed that micron scale storage spaces mainly composed of fractures and nanometer scale pores and fractures form multi-scale dual porosity system.Low resource abundance,small single well controlled reserve,and low production are related to the nano-scale pore space in Da’anzhai Memer,whereas the dual-porosity system composed of pores and fractures makes for long-term oil yield.Due to the existence of abundant slot-like pore space and fractures,economic tight oil production was achieved without stimulations.