The sandstones of the paleogene in the Huimin Depression have undergone numerous diagenetic processes, such as compaction, cementation, dissolution, metasomasis and recrystallization. The first three — compaction, ...The sandstones of the paleogene in the Huimin Depression have undergone numerous diagenetic processes, such as compaction, cementation, dissolution, metasomasis and recrystallization. The first three — compaction, cementation and dissolution — affect reservoir properties most intensively. An average porosity loss due to compaction is 0.78% per 100 meters, slightly higher in the central and southern parts and lower in the northern. Cementation has resulted in the porosity loss from 8% to 20% at a depth below 1,500 meters. Dissolution, which in most cases is the dissolution of feldspar and of carbonate cement, primarily occurs in two depth intervals, from 1,400 to 2,500 meters and 2,700 to 4,000 meters respectively. New porosity is created through dissolution from 4% to 14%. The sandstones experienced stage A and stage B of early diagenesis and stage A of late diagenesis. At present, most of them are experiencing Phase A2 of late diagenesis. The types of pores in the sand reservoir can be grouped into primary and secondary ones.展开更多
Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and r...Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and reservoir quality of the fourth member sandstones of Shahejie formation (Es4). The Es4 sandstones are mostly arkose and lithic arkose, rarely feldspathic litharenite, with an average mass fraction of quartz 51.6%, feldspar 33.8% and rock fragments 14.6% (Q51.6F33.8R14.6). They have an average framework composition (mass fraction) of quartz 57.10%, K-feldspar 5.76%, sodium-calcium feldspar 13.00%, calcite 5.77%, dolomite 5.63%, siderite 0.95%, pyrite 0.30%, anhydrite 0.04%, and clay mineral 11.46%. The diagenentic minerals typically include kaolinite, illite-smectite (I/S), illite, chlorite, authigenetic quartz and feldspar, and carbonate and pyrite. Es4 sandstone has undergone stages A and B of eodiagenesis, and now, it is experiencing stage A of mesodiagenesis. Reservoir quality is predominantly controlled by the mechanical compaction, for example, 45.65% of the original porosity loss is related to compaction. The original porosity loss related with cementation is only 26.00%. The reservoir quality is improved as a result of dissolution of feldspar, rock fragment and so forth. The porosity evolved from dissolution varies from 3% to 4%.展开更多
In recent years, with the increase of the depth of open-pit mining, the pollution level has been on the rise due to harmful gases and dust occurring in the process of mining. In order to accelerate the diffusion of th...In recent years, with the increase of the depth of open-pit mining, the pollution level has been on the rise due to harmful gases and dust occurring in the process of mining. In order to accelerate the diffusion of these air pollutants, the distributed regularity of the rock face temperature which is directly related to the air ventilation in deep open-pit mines should be studied. Here, we establish the key factors influencing the rock face temperature in a deep open-pit mine. We also present an empirical model of the rock face temperature variation in the deep open-pit mine, of which the performance is interestingly high compared with that of the field test. This study lays a foundation to study the ventilation thermodynamic theory in the deep open-pit mine, which is of great importance for theoretical studies and engineering applications of solving air pollution problem in deep open-pit mines.展开更多
Core and cast sections observation and description,and logging,scanning electron microscope and core lab analysis data etc. were applied to the present research of the characteristics and mechanism of low permeability...Core and cast sections observation and description,and logging,scanning electron microscope and core lab analysis data etc. were applied to the present research of the characteristics and mechanism of low permeability beach-bar sandstone reservoir of Es4 in Dongying sag. The results indicated the reservoir has the characteristics of middle-low pores,low-permeability,low compositional and structural maturity,and thin throat. The low-permeability is mainly due to sedimentation (fine particles and argillaceous inter beds) and diagenesis (compaction,cementation,and dissolution). The cementation reduced the physical property of the reservoir mainly by carbonate cementation,quartz autogeny and enragement,and autogeny clay. Clay minerals usually jam the pores by filling holes,close-fitting the wall of hole,bridging,wrapping grains,and separate attaching the pores and so on. The dissolution is insufficient so as not to improve the porosity and permeability of the reservoir obviously. So it is also an important factor of forming low-permeability reservoir.展开更多
The Es3/3-Es1/4 shales in Dongying sag are source rocks with large reserves of shale oil and gas. For the iden- tification of development characteristics and geological significance of the reservoir space, FM1 logging...The Es3/3-Es1/4 shales in Dongying sag are source rocks with large reserves of shale oil and gas. For the iden- tification of development characteristics and geological significance of the reservoir space, FM1 logging, core observation, thin section analysis, X-ray diffraction, fluorescence microscopy, scanning electron microscopy, mercury porosimetry, low-temperature nitrogen adsorption, atomic force microscopy, and conventional physical property testing were used to study the petrology and reservoir space of the Es3/3-Es1/4 shale in Dongying sag. The results suggest that the shale is rich in carbonate minerals. Phanero- crystalline stratiform and lamellar argillaceous limestone and calcareous claystone are the oil- and gas-bearing lithofacies. The oil in the micropores is mainly present as membranes and clots. The shale reservoir space has a network structure with veins, carbonate and clay minerals, and micropores among pyrite and the matrix. The results provide the geological framework for future shale oil and gas explora- tion in Dongying sag.展开更多
Based on the data of 44 samples of hydrocarbon source rocks in Nanpu No.3 buffed-hill region, the kerogen type is judged through the pyrolysis and microscopic identification. At the same time, organic matter maturity ...Based on the data of 44 samples of hydrocarbon source rocks in Nanpu No.3 buffed-hill region, the kerogen type is judged through the pyrolysis and microscopic identification. At the same time, organic matter maturity and hydrocarbon generation threshold are studied by using vitrinite reflectance, pyrolysis yield and hydrocarbon abundance. Meanwhile the hydrocarbon expulsion threshold is calculated. And the characteristics of organic hydrocarbon generation and expulsion are preliminarily revealed and evaluated. The result shows that the No.3 buffed-hill region has abundant hydrocarbon source rocks with high content of organic carbon. And the primary types of kerogen are II, and lI 2. The hydrocarbon source rocks which passed biochemistry, thermolysis and thermal cracking have developed into the mature-postmature phase of different extents. And plenty of oil and gas were expelled out. It is believed the depth of oil-generating window is 3 600 m and the depth of hydro- carbon-expulsion threshold is 4 100 m. The comprehensive analysis indicates that Nanpu No.3 burried-hill region has a certain condition to generate hydrocarbon which is very promising in oil exploration and thus can become an important exploration and development target next.展开更多
Maintaining caprock integrity is prerequisite for hydrocarbon accumulation. And gypsolyte caprock integrity is mainly affected by fracturing. Composition, damage behavior and mechanical strength of Paleocene Artashi F...Maintaining caprock integrity is prerequisite for hydrocarbon accumulation. And gypsolyte caprock integrity is mainly affected by fracturing. Composition, damage behavior and mechanical strength of Paleocene Artashi Formation gypsolyte rock that seals significant petroleum in the Kashi Sag of Tarim Basin had been revealed via X-ray diffraction and triaxial compression test. The results indicate the Artashi Formation can be lithologically divided into the lower and upper lithologic members. The lower member comprises gypsum as the dominant mineral, and the cohesion and friction coefficient are 8 MPa and 0.315, respectively. Similarly, the upper lithologic member consists mainly of anhydrite at the cohesion and coefficient of internal friction values of 18 MPa and 0.296. Given that the failure criterion and brittle-ductile transition factors during burial, the sealing integrity of Artashi Formation can be quantized for seven different stages. The reservoirs at the bottom of Artashi Formation caprock buried from 2285 m to 3301 m are expected to be the most favorable exploration target in the Kashi Sag.展开更多
文摘The sandstones of the paleogene in the Huimin Depression have undergone numerous diagenetic processes, such as compaction, cementation, dissolution, metasomasis and recrystallization. The first three — compaction, cementation and dissolution — affect reservoir properties most intensively. An average porosity loss due to compaction is 0.78% per 100 meters, slightly higher in the central and southern parts and lower in the northern. Cementation has resulted in the porosity loss from 8% to 20% at a depth below 1,500 meters. Dissolution, which in most cases is the dissolution of feldspar and of carbonate cement, primarily occurs in two depth intervals, from 1,400 to 2,500 meters and 2,700 to 4,000 meters respectively. New porosity is created through dissolution from 4% to 14%. The sandstones experienced stage A and stage B of early diagenesis and stage A of late diagenesis. At present, most of them are experiencing Phase A2 of late diagenesis. The types of pores in the sand reservoir can be grouped into primary and secondary ones.
基金Project(2006AA09Z336) supported by the National High-Tech Research and Development Program of China
文摘Petrographic analysis combined with various techniques, such as scanning electron microscopy and X-ray diffraction, was used to assess the timing of growth and original mineral cements, the controls on reservoir and reservoir quality of the fourth member sandstones of Shahejie formation (Es4). The Es4 sandstones are mostly arkose and lithic arkose, rarely feldspathic litharenite, with an average mass fraction of quartz 51.6%, feldspar 33.8% and rock fragments 14.6% (Q51.6F33.8R14.6). They have an average framework composition (mass fraction) of quartz 57.10%, K-feldspar 5.76%, sodium-calcium feldspar 13.00%, calcite 5.77%, dolomite 5.63%, siderite 0.95%, pyrite 0.30%, anhydrite 0.04%, and clay mineral 11.46%. The diagenentic minerals typically include kaolinite, illite-smectite (I/S), illite, chlorite, authigenetic quartz and feldspar, and carbonate and pyrite. Es4 sandstone has undergone stages A and B of eodiagenesis, and now, it is experiencing stage A of mesodiagenesis. Reservoir quality is predominantly controlled by the mechanical compaction, for example, 45.65% of the original porosity loss is related to compaction. The original porosity loss related with cementation is only 26.00%. The reservoir quality is improved as a result of dissolution of feldspar, rock fragment and so forth. The porosity evolved from dissolution varies from 3% to 4%.
基金Project(51274023) supported by the National Natural Science Foundation of ChinaProject(FRF-BD-17-007A) supported by Fundamental Research Funds for the Central Universities,China
文摘In recent years, with the increase of the depth of open-pit mining, the pollution level has been on the rise due to harmful gases and dust occurring in the process of mining. In order to accelerate the diffusion of these air pollutants, the distributed regularity of the rock face temperature which is directly related to the air ventilation in deep open-pit mines should be studied. Here, we establish the key factors influencing the rock face temperature in a deep open-pit mine. We also present an empirical model of the rock face temperature variation in the deep open-pit mine, of which the performance is interestingly high compared with that of the field test. This study lays a foundation to study the ventilation thermodynamic theory in the deep open-pit mine, which is of great importance for theoretical studies and engineering applications of solving air pollution problem in deep open-pit mines.
基金Project P06012 supported by the Key Research Project of SINOPEC
文摘Core and cast sections observation and description,and logging,scanning electron microscope and core lab analysis data etc. were applied to the present research of the characteristics and mechanism of low permeability beach-bar sandstone reservoir of Es4 in Dongying sag. The results indicated the reservoir has the characteristics of middle-low pores,low-permeability,low compositional and structural maturity,and thin throat. The low-permeability is mainly due to sedimentation (fine particles and argillaceous inter beds) and diagenesis (compaction,cementation,and dissolution). The cementation reduced the physical property of the reservoir mainly by carbonate cementation,quartz autogeny and enragement,and autogeny clay. Clay minerals usually jam the pores by filling holes,close-fitting the wall of hole,bridging,wrapping grains,and separate attaching the pores and so on. The dissolution is insufficient so as not to improve the porosity and permeability of the reservoir obviously. So it is also an important factor of forming low-permeability reservoir.
基金funded by the Scientific and Technological Brainstorm Project of Sinopec Corp (No. P12062)
文摘The Es3/3-Es1/4 shales in Dongying sag are source rocks with large reserves of shale oil and gas. For the iden- tification of development characteristics and geological significance of the reservoir space, FM1 logging, core observation, thin section analysis, X-ray diffraction, fluorescence microscopy, scanning electron microscopy, mercury porosimetry, low-temperature nitrogen adsorption, atomic force microscopy, and conventional physical property testing were used to study the petrology and reservoir space of the Es3/3-Es1/4 shale in Dongying sag. The results suggest that the shale is rich in carbonate minerals. Phanero- crystalline stratiform and lamellar argillaceous limestone and calcareous claystone are the oil- and gas-bearing lithofacies. The oil in the micropores is mainly present as membranes and clots. The shale reservoir space has a network structure with veins, carbonate and clay minerals, and micropores among pyrite and the matrix. The results provide the geological framework for future shale oil and gas explora- tion in Dongying sag.
文摘Based on the data of 44 samples of hydrocarbon source rocks in Nanpu No.3 buffed-hill region, the kerogen type is judged through the pyrolysis and microscopic identification. At the same time, organic matter maturity and hydrocarbon generation threshold are studied by using vitrinite reflectance, pyrolysis yield and hydrocarbon abundance. Meanwhile the hydrocarbon expulsion threshold is calculated. And the characteristics of organic hydrocarbon generation and expulsion are preliminarily revealed and evaluated. The result shows that the No.3 buffed-hill region has abundant hydrocarbon source rocks with high content of organic carbon. And the primary types of kerogen are II, and lI 2. The hydrocarbon source rocks which passed biochemistry, thermolysis and thermal cracking have developed into the mature-postmature phase of different extents. And plenty of oil and gas were expelled out. It is believed the depth of oil-generating window is 3 600 m and the depth of hydro- carbon-expulsion threshold is 4 100 m. The comprehensive analysis indicates that Nanpu No.3 burried-hill region has a certain condition to generate hydrocarbon which is very promising in oil exploration and thus can become an important exploration and development target next.
基金Project(41672121)supported by the National Natural Science Foundation of ChinaProject(D1438)supported by the China Geological Survey
文摘Maintaining caprock integrity is prerequisite for hydrocarbon accumulation. And gypsolyte caprock integrity is mainly affected by fracturing. Composition, damage behavior and mechanical strength of Paleocene Artashi Formation gypsolyte rock that seals significant petroleum in the Kashi Sag of Tarim Basin had been revealed via X-ray diffraction and triaxial compression test. The results indicate the Artashi Formation can be lithologically divided into the lower and upper lithologic members. The lower member comprises gypsum as the dominant mineral, and the cohesion and friction coefficient are 8 MPa and 0.315, respectively. Similarly, the upper lithologic member consists mainly of anhydrite at the cohesion and coefficient of internal friction values of 18 MPa and 0.296. Given that the failure criterion and brittle-ductile transition factors during burial, the sealing integrity of Artashi Formation can be quantized for seven different stages. The reservoirs at the bottom of Artashi Formation caprock buried from 2285 m to 3301 m are expected to be the most favorable exploration target in the Kashi Sag.
