The multi-stage minerals filled in pore space were sequenced, and the charging stages of fluid and hydrocarbon were reconstructed based on the observation of drilling cores and thin sections, homogeneous temperature t...The multi-stage minerals filled in pore space were sequenced, and the charging stages of fluid and hydrocarbon were reconstructed based on the observation of drilling cores and thin sections, homogeneous temperature testing of fluid inclusions, Laser Raman composition analysis and isotope geochemical analysis. The Cambrian Longwangmiao Formation in the study area went through 5 stages of fluid charging, in which 3 stages, mid-late Triassic, early-mid Jurassic and early-mid Cretaceous, were related to oil and gas charging. Especially the oil and gas charging event in early-mid Cretaceous was the critical period of gas accumulation in the study area, and was recorded by methane gas inclusions in the late stage quartz fillings. The ^(40) Ar-^(39) Ar dating of the 3 rd stage methane inclusions shows that the natural gas charging of this stage was from 125.8±8.2 Ma. Analysis of Si, O isotopes and ^(87) Sr/^(86) Sr of the late stage quartz indicates that the fluid source of the quartz was formation water coming from long term evolution and concentration of meteoric water, but not from deep part or other sources, this also reflects that, in the critical charging period of natural gas, the Cambrian Longwangmiao Formation in Moxi structure had favorable conservation conditions for hydrocarbon accumulation, which was favorable for the formation of the Longwangmiao large natural gas pool.展开更多
By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reser...By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reservoirs in this area were established, and the main factors affecting the development of high quality reservoir were determined. By employing Formation MicroScanner Image(FMI) logging fracture-cavity recognition technology and reservoir seismic waveform classification technology, the spatial distribution of reservoirs of all grades were predicted. On the basis of identifying four types of reservoir space developed in the study area by mercury injection experiment, a classification criterion was established using four reservoir grading evaluation parameters, median throat radius, effective porosity and effective permeability of fracture-cavity development zone, relationship between fracture and dissolution pore development and assemblage, and the reservoirs in the study area were classified into grade I high quality reservoir of fracture and cavity type, grade II average reservoir of fracture and porosity type, grade Ⅲ poor reservoir of intergranular pore type. Based on the three main factors controlling the development of high quality reservoir, structural location, sedimentary facies and epigenesis, the distribution of the 3 grades reservoirs in each well area and formation were predicted using geophysical response and percolation characteristics. Follow-up drilling has confirmed that the classification evaluation standard and prediction methods established are effective.展开更多
基金Supported by the National Natural Science Foundation of China(41572133,41372141)
文摘The multi-stage minerals filled in pore space were sequenced, and the charging stages of fluid and hydrocarbon were reconstructed based on the observation of drilling cores and thin sections, homogeneous temperature testing of fluid inclusions, Laser Raman composition analysis and isotope geochemical analysis. The Cambrian Longwangmiao Formation in the study area went through 5 stages of fluid charging, in which 3 stages, mid-late Triassic, early-mid Jurassic and early-mid Cretaceous, were related to oil and gas charging. Especially the oil and gas charging event in early-mid Cretaceous was the critical period of gas accumulation in the study area, and was recorded by methane gas inclusions in the late stage quartz fillings. The ^(40) Ar-^(39) Ar dating of the 3 rd stage methane inclusions shows that the natural gas charging of this stage was from 125.8±8.2 Ma. Analysis of Si, O isotopes and ^(87) Sr/^(86) Sr of the late stage quartz indicates that the fluid source of the quartz was formation water coming from long term evolution and concentration of meteoric water, but not from deep part or other sources, this also reflects that, in the critical charging period of natural gas, the Cambrian Longwangmiao Formation in Moxi structure had favorable conservation conditions for hydrocarbon accumulation, which was favorable for the formation of the Longwangmiao large natural gas pool.
基金Supported by CNPC Science and Technology Major Project(2016ZX052,2016ZX05015-003)
文摘By using core, thin section, well logging, seismic, well testing and other data, the reservoir grading evaluation parameters were selected, the classification criterion considering multiple factors for carbonate reservoirs in this area were established, and the main factors affecting the development of high quality reservoir were determined. By employing Formation MicroScanner Image(FMI) logging fracture-cavity recognition technology and reservoir seismic waveform classification technology, the spatial distribution of reservoirs of all grades were predicted. On the basis of identifying four types of reservoir space developed in the study area by mercury injection experiment, a classification criterion was established using four reservoir grading evaluation parameters, median throat radius, effective porosity and effective permeability of fracture-cavity development zone, relationship between fracture and dissolution pore development and assemblage, and the reservoirs in the study area were classified into grade I high quality reservoir of fracture and cavity type, grade II average reservoir of fracture and porosity type, grade Ⅲ poor reservoir of intergranular pore type. Based on the three main factors controlling the development of high quality reservoir, structural location, sedimentary facies and epigenesis, the distribution of the 3 grades reservoirs in each well area and formation were predicted using geophysical response and percolation characteristics. Follow-up drilling has confirmed that the classification evaluation standard and prediction methods established are effective.
