Our recent archaeological expeditions in the Siuyu and Ughaugha wards of Singida eastern province have recuperated the very compelling rock engravings (petroglyphs) that weren’t reported in Tanzania before. Archaeolo...Our recent archaeological expeditions in the Siuyu and Ughaugha wards of Singida eastern province have recuperated the very compelling rock engravings (petroglyphs) that weren’t reported in Tanzania before. Archaeologically, Singida’s fame emanated from her endowments of rock paintings. However;during this research, we did discover rock cupules, gongs, and grinding hollows art together with rock paintings (pictographs) that have opened up a new avenue for rock art studies in Tanzania. We carried out intensive site surveys around four sites namely Siuyu, Ngaghe, Misimbwa and Ughaugha B with the aims of solely examining, recording, and documenting archaeological artifacts on the surface in order to research the cultural and behavioural patterns of early humans in the Singida region. Surveys also enabled us to locate suitable areas where future excavations would be established. In some cases, ethnographic enquiries were employed to get supplementary information on the present-day use of rock art sites. Besides, we interviewed local people to assess their general understanding of the presence of more sites or helping in locating, and discovering new sites. Through ethnographic inquiries, we discovered several sites with substantial number of rock engravings that were never document by any researcher. On top of that, this study reports other archaeological potentials of the region by describing in detail their significances for future research undertakings. Additionally, this paper article reports on the occurrence of Middle Stone Age (MSA) archaeological assemblages from the open-air site and the presence of grinding hollows and rock cupules (Siuyu complexes) in central Tanzania for the first time.展开更多
Interpreting reservoir properties through log data and logging responses in complex strata is critical for efficient petroleum exploitation,particularly for metamorphic rocks.However,the unsatisfactory accuracy of suc...Interpreting reservoir properties through log data and logging responses in complex strata is critical for efficient petroleum exploitation,particularly for metamorphic rocks.However,the unsatisfactory accuracy of such interpretations in complex reservoirs has hindered their widespread application,resulting in severe inconvenience.In this study,we proposed a multi-mineral model based on the least-square method and an optimal principle to interpret the logging responses and petrophysical properties of complex hydrocarbon reservoirs.We began by selecting the main minerals based on a comprehensive analysis of log data,X-ray diffraction,petrographic thin sections and scanning electron microscopy(SEM)for three wells in the Bozhong 19-6 structural zone.In combination of the physical properties of these minerals with logging responses,we constructed the multi-mineral model,which can predict the log curves,petrophysical properties and mineral profile.The predicted and measured log data are evaluated using a weighted average error,which shows that the multi-mineral model has satisfactory prediction performance with errors below 11%in most intervals.Finally,we apply the model to a new well“x”in the Bozhong 19-6 structural zone,and the predicted logging responses match well with measured data with the weighted average error below 11.8%for most intervals.Moreover,the lithology is dominated by plagioclase,K-feldspar,and quartz as shown by the mineral profile,which correlates with the lithology of the Archean metamorphic rocks in this region.It is concluded that the multi-mineral model presented in this study provides reasonable methods for interpreting log data in complex metamorphic hydrocarbon reservoirs and could assist in efficient development in the future.展开更多
Huashan rock painting is a representative of the rock art complex in Zuojiang River in Guangxi Zhuang Autonomous Region,and it is the largest and the most well preserved rock painting found in China,with a wide distri...Huashan rock painting is a representative of the rock art complex in Zuojiang River in Guangxi Zhuang Autonomous Region,and it is the largest and the most well preserved rock painting found in China,with a wide distribution of locations and the richest content of images.Due to its grand scale,spectacular scenes,and numerous images,it has become a typical representative of rock painting in Zuojiang River basin of Guangxi and is famous all over the world.In 1988,it was announced as a key cultural relics protection unit by the State Council,and in 2016,“Zuojiang River Huashan Rock Art Cultural Landscape”was successfully applied for the List of World Heritage,which makes it important to the inheritance and protection of Huashan rock paintings.In the past 10 years,with the successful holding of China-ASEAN Expo,the distinctive tourist products of Guangxi Zhuang nationality and the culture creative product industry have been vigorously developed and recognized by domestic and foreign markets.The culture of Guangxi Zuojiang Huashan rock painting can be presented in the form of cultural and creative products,so that Guangxi Zuojiang River Huashan rock art can be known by more people.展开更多
As a cultural relic,the Guizhou rock paintings are very important for the study of prehistory,minority cus-toms and comparative folklore.They attract an increasing number of visi-tors and scholars with their unique,my...As a cultural relic,the Guizhou rock paintings are very important for the study of prehistory,minority cus-toms and comparative folklore.They attract an increasing number of visi-tors and scholars with their unique,mysterious images and have become yet another spot of interest in Gui-zhou's tourism industry,taking their place beside the famous Huangguo-shu Waterfall,the karst cave Dragon Palace and the Tianxingqiao Stone Forest.展开更多
目的研究ROCK/SLUG信号通路在内皮素-1(endo-thelin-1,ET-1)促进人卵巢癌细胞上皮向间充质转分化(epi-thelial to mesenchymal transition,EMT)中的作用。方法 ET-1处理人卵巢癌细胞株SK-OV-3和CaOV3,或共用ROCK的活化突变体转染细胞或...目的研究ROCK/SLUG信号通路在内皮素-1(endo-thelin-1,ET-1)促进人卵巢癌细胞上皮向间充质转分化(epi-thelial to mesenchymal transition,EMT)中的作用。方法 ET-1处理人卵巢癌细胞株SK-OV-3和CaOV3,或共用ROCK的活化突变体转染细胞或加入ROCK的抑制剂Y27632,并转染含SLUG启动子的pGL3质粒与Renilla质粒。实验末用Boyden小室体外侵袭实验检测细胞侵袭能力,细胞免疫荧光染色观察细胞形态,报告基因检测试剂盒检测SLUG启动子活性,用实时定量PCR和Western bot方法检测EMT相关基因的表达。结果 ET-1诱导SK-OV-3和CaOV3发生与EMT相一致的形态和基因变化,促进其细胞侵袭力;ET-1与内皮素A受体(endothelin A receptor,ETAR)结合,促进转录因子SLUG的转录;ET-1促进ROCK及fibronectin的表达,同时转染ROCK的活化突变体,促进ET-1诱导的fibronectin表达以及细胞侵袭力的增加。相反,ROCK抑制剂Y27632抑制ET-1对fibronectin表达以及细胞侵袭力的促进作用;转染ROCK的活化突变体,上调SLUG基因转录启动子活性促进其转录,抑制E-cadherin的转录。相反,ROCK的抑制剂Y27632抑制SLUG基因启动子的活性。结论 ET-1通过活化ROCK/SLUG通路促进人卵巢癌细胞发生EMT。展开更多
In many situations rocks are subjected to biaxial loading and the failure process is controlled by the lateral confinement stresses. The importance of confinement stresses has been recognized in the literature by many...In many situations rocks are subjected to biaxial loading and the failure process is controlled by the lateral confinement stresses. The importance of confinement stresses has been recognized in the literature by many researchers, in particular, its influence on strength and on the angle of fracture, but still there is not a clear description for the influence of confining stress on the crack propagation mechanism of rocks. This paper presents a numerical pro- cedure for the analysis of crack propagation in rock-like ma- terials under compressive biaxial loads. Several numerical simulations of biaxial tests on the rock specimen have been carried out by a bonded particle model （BPM） and the influ- ence of confinement on the mechanism of crack propagation from a single flaw in rock specimens is studied. For this purpose, several biaxial compressive tests on rectangular spec- imens under different confinement stresses were modeled in （2 dimensional particle flow code） PFC2D. The results show that wing cracks initiate perpendicular to the flaw and trend toward the direction of major stress, however, when the lat- eral stresses increase, this initiation angle gets wider. Also it is concluded that in addition to the material type, the initiation direction of the secondary cracks depends on confine- ment stresses, too. Besides, it is understood that secondary cracks may be produced from both tensile and shear mechanisms.展开更多
Kerogen content and kerogen porosity play a significant role in elastic properties of organic-rich shales. We construct a rock physics model for organic-rich shales to quantify the effect of kerogen content and keroge...Kerogen content and kerogen porosity play a significant role in elastic properties of organic-rich shales. We construct a rock physics model for organic-rich shales to quantify the effect of kerogen content and kerogen porosity using the Kuster and Toks6z theory and the selfconsistent approximation method. Rock physics modeling results show that with the increase of kerogen content and kerogen-related porosity, the velocity and density of shales decrease, and the effect of kerogen porosity becomes more obvious only for higher kerogen content. We also find that the Poisson＇s ratio of the shale is not sensitive to kerogen porosity for the case of gas saturation. Finally, for the seismic reflection responses of an organic-rich shale layer, forward modeling results indicate the fifth type AVO re- sponses which correspond to a negative intercept and a positive gradient. The absolute values of intercept and gradient increase with kerogen content and kerogen porosity, and present predictable variations associated with velocities and density.展开更多
Hydrocarbon-producing lacustrine basins are widely developed in the world, and China has a large number of lacustrine basins that have developed since the early Permian. The organic-rich shale-dominated heterogeneous ...Hydrocarbon-producing lacustrine basins are widely developed in the world, and China has a large number of lacustrine basins that have developed since the early Permian. The organic-rich shale-dominated heterogeneous source rock intervals in Chinese lacustrine basins generally contain frequent thin interbeds of stratigraphically associated sandstone, siltstone, marl, dolomite, and limestone. The concept of ‘‘Hybrid Plays＇ ＇ as put forth in this article recognizes this pattern of alternating organicrich shale and organic-lean interbeds and existence of mixed unconventional and conventional plays. Hybrid Plays in lacustrine source rock intervals present a unique closed petroleum system hosting continuous hydrocarbons.The interbedded organic-lean siliciclastic and/or carbonateplays are efficiently charged with hydrocarbons via short migration pathways from the adjacent organic-rich shale that is often also a self-sourced play. We assert ‘‘Hybrid Plays＇ ＇ provide the most realistic exploration model for targeting multiple-stacked and genetically related very tight shale, tight and conventional plays together in the entire source rock interval rather than individual plays only. The Hybrid Play model has been proven and works for a wide variety of lacustrine rift, sag and foreland basins in China.展开更多
文摘Our recent archaeological expeditions in the Siuyu and Ughaugha wards of Singida eastern province have recuperated the very compelling rock engravings (petroglyphs) that weren’t reported in Tanzania before. Archaeologically, Singida’s fame emanated from her endowments of rock paintings. However;during this research, we did discover rock cupules, gongs, and grinding hollows art together with rock paintings (pictographs) that have opened up a new avenue for rock art studies in Tanzania. We carried out intensive site surveys around four sites namely Siuyu, Ngaghe, Misimbwa and Ughaugha B with the aims of solely examining, recording, and documenting archaeological artifacts on the surface in order to research the cultural and behavioural patterns of early humans in the Singida region. Surveys also enabled us to locate suitable areas where future excavations would be established. In some cases, ethnographic enquiries were employed to get supplementary information on the present-day use of rock art sites. Besides, we interviewed local people to assess their general understanding of the presence of more sites or helping in locating, and discovering new sites. Through ethnographic inquiries, we discovered several sites with substantial number of rock engravings that were never document by any researcher. On top of that, this study reports other archaeological potentials of the region by describing in detail their significances for future research undertakings. Additionally, this paper article reports on the occurrence of Middle Stone Age (MSA) archaeological assemblages from the open-air site and the presence of grinding hollows and rock cupules (Siuyu complexes) in central Tanzania for the first time.
基金funded by Science and Technology Major Project of China National Offshore Oil Corporation(CNOOC-KJ 135 ZDXM36 TJ 08TJ).
文摘Interpreting reservoir properties through log data and logging responses in complex strata is critical for efficient petroleum exploitation,particularly for metamorphic rocks.However,the unsatisfactory accuracy of such interpretations in complex reservoirs has hindered their widespread application,resulting in severe inconvenience.In this study,we proposed a multi-mineral model based on the least-square method and an optimal principle to interpret the logging responses and petrophysical properties of complex hydrocarbon reservoirs.We began by selecting the main minerals based on a comprehensive analysis of log data,X-ray diffraction,petrographic thin sections and scanning electron microscopy(SEM)for three wells in the Bozhong 19-6 structural zone.In combination of the physical properties of these minerals with logging responses,we constructed the multi-mineral model,which can predict the log curves,petrophysical properties and mineral profile.The predicted and measured log data are evaluated using a weighted average error,which shows that the multi-mineral model has satisfactory prediction performance with errors below 11%in most intervals.Finally,we apply the model to a new well“x”in the Bozhong 19-6 structural zone,and the predicted logging responses match well with measured data with the weighted average error below 11.8%for most intervals.Moreover,the lithology is dominated by plagioclase,K-feldspar,and quartz as shown by the mineral profile,which correlates with the lithology of the Archean metamorphic rocks in this region.It is concluded that the multi-mineral model presented in this study provides reasonable methods for interpreting log data in complex metamorphic hydrocarbon reservoirs and could assist in efficient development in the future.
基金This paper is the promotion project of basic ability of scientific research of young and middle-aged teachers in Guangxi universities-the phase research result of Application and Research of Huashan Rock Paintings in Cultural and Creative Products,with the project No.of 2019KY0891.
文摘Huashan rock painting is a representative of the rock art complex in Zuojiang River in Guangxi Zhuang Autonomous Region,and it is the largest and the most well preserved rock painting found in China,with a wide distribution of locations and the richest content of images.Due to its grand scale,spectacular scenes,and numerous images,it has become a typical representative of rock painting in Zuojiang River basin of Guangxi and is famous all over the world.In 1988,it was announced as a key cultural relics protection unit by the State Council,and in 2016,“Zuojiang River Huashan Rock Art Cultural Landscape”was successfully applied for the List of World Heritage,which makes it important to the inheritance and protection of Huashan rock paintings.In the past 10 years,with the successful holding of China-ASEAN Expo,the distinctive tourist products of Guangxi Zhuang nationality and the culture creative product industry have been vigorously developed and recognized by domestic and foreign markets.The culture of Guangxi Zuojiang Huashan rock painting can be presented in the form of cultural and creative products,so that Guangxi Zuojiang River Huashan rock art can be known by more people.
文摘As a cultural relic,the Guizhou rock paintings are very important for the study of prehistory,minority cus-toms and comparative folklore.They attract an increasing number of visi-tors and scholars with their unique,mysterious images and have become yet another spot of interest in Gui-zhou's tourism industry,taking their place beside the famous Huangguo-shu Waterfall,the karst cave Dragon Palace and the Tianxingqiao Stone Forest.
文摘目的研究ROCK/SLUG信号通路在内皮素-1(endo-thelin-1,ET-1)促进人卵巢癌细胞上皮向间充质转分化(epi-thelial to mesenchymal transition,EMT)中的作用。方法 ET-1处理人卵巢癌细胞株SK-OV-3和CaOV3,或共用ROCK的活化突变体转染细胞或加入ROCK的抑制剂Y27632,并转染含SLUG启动子的pGL3质粒与Renilla质粒。实验末用Boyden小室体外侵袭实验检测细胞侵袭能力,细胞免疫荧光染色观察细胞形态,报告基因检测试剂盒检测SLUG启动子活性,用实时定量PCR和Western bot方法检测EMT相关基因的表达。结果 ET-1诱导SK-OV-3和CaOV3发生与EMT相一致的形态和基因变化,促进其细胞侵袭力;ET-1与内皮素A受体(endothelin A receptor,ETAR)结合,促进转录因子SLUG的转录;ET-1促进ROCK及fibronectin的表达,同时转染ROCK的活化突变体,促进ET-1诱导的fibronectin表达以及细胞侵袭力的增加。相反,ROCK抑制剂Y27632抑制ET-1对fibronectin表达以及细胞侵袭力的促进作用;转染ROCK的活化突变体,上调SLUG基因转录启动子活性促进其转录,抑制E-cadherin的转录。相反,ROCK的抑制剂Y27632抑制SLUG基因启动子的活性。结论 ET-1通过活化ROCK/SLUG通路促进人卵巢癌细胞发生EMT。
文摘In many situations rocks are subjected to biaxial loading and the failure process is controlled by the lateral confinement stresses. The importance of confinement stresses has been recognized in the literature by many researchers, in particular, its influence on strength and on the angle of fracture, but still there is not a clear description for the influence of confining stress on the crack propagation mechanism of rocks. This paper presents a numerical pro- cedure for the analysis of crack propagation in rock-like ma- terials under compressive biaxial loads. Several numerical simulations of biaxial tests on the rock specimen have been carried out by a bonded particle model （BPM） and the influ- ence of confinement on the mechanism of crack propagation from a single flaw in rock specimens is studied. For this purpose, several biaxial compressive tests on rectangular spec- imens under different confinement stresses were modeled in （2 dimensional particle flow code） PFC2D. The results show that wing cracks initiate perpendicular to the flaw and trend toward the direction of major stress, however, when the lat- eral stresses increase, this initiation angle gets wider. Also it is concluded that in addition to the material type, the initiation direction of the secondary cracks depends on confine- ment stresses, too. Besides, it is understood that secondary cracks may be produced from both tensile and shear mechanisms.
基金supported by the National Natural Science Foundation of China under Grants U1262208the National Natural Science Foundation of China under Grants 41404090
文摘Kerogen content and kerogen porosity play a significant role in elastic properties of organic-rich shales. We construct a rock physics model for organic-rich shales to quantify the effect of kerogen content and kerogen porosity using the Kuster and Toks6z theory and the selfconsistent approximation method. Rock physics modeling results show that with the increase of kerogen content and kerogen-related porosity, the velocity and density of shales decrease, and the effect of kerogen porosity becomes more obvious only for higher kerogen content. We also find that the Poisson＇s ratio of the shale is not sensitive to kerogen porosity for the case of gas saturation. Finally, for the seismic reflection responses of an organic-rich shale layer, forward modeling results indicate the fifth type AVO re- sponses which correspond to a negative intercept and a positive gradient. The absolute values of intercept and gradient increase with kerogen content and kerogen porosity, and present predictable variations associated with velocities and density.
基金National Natural Science Foundation of China (Grant Numbers 40872077 and 41272122)China National Key Technology Research and Development Program (Grant Number 2001BA605A09-1)+1 种基金Sinopec’s Petroleum Exploration and Production Research Institute (Grant No. G5800-15-ZS-WX038)EGI’s China Shale Gas and Shale Oil Plays Consortia (100980) sponsored by 20 multi-national oil companies
文摘Hydrocarbon-producing lacustrine basins are widely developed in the world, and China has a large number of lacustrine basins that have developed since the early Permian. The organic-rich shale-dominated heterogeneous source rock intervals in Chinese lacustrine basins generally contain frequent thin interbeds of stratigraphically associated sandstone, siltstone, marl, dolomite, and limestone. The concept of ‘‘Hybrid Plays＇ ＇ as put forth in this article recognizes this pattern of alternating organicrich shale and organic-lean interbeds and existence of mixed unconventional and conventional plays. Hybrid Plays in lacustrine source rock intervals present a unique closed petroleum system hosting continuous hydrocarbons.The interbedded organic-lean siliciclastic and/or carbonateplays are efficiently charged with hydrocarbons via short migration pathways from the adjacent organic-rich shale that is often also a self-sourced play. We assert ‘‘Hybrid Plays＇ ＇ provide the most realistic exploration model for targeting multiple-stacked and genetically related very tight shale, tight and conventional plays together in the entire source rock interval rather than individual plays only. The Hybrid Play model has been proven and works for a wide variety of lacustrine rift, sag and foreland basins in China.
