Brittleness analysis becomes important when looking for sweet spots in tightoil sandstone reservoirs. Hence, appropriate indices are required as accurate brittleness evaluation criteria. We construct a seismic rock ph...Brittleness analysis becomes important when looking for sweet spots in tightoil sandstone reservoirs. Hence, appropriate indices are required as accurate brittleness evaluation criteria. We construct a seismic rock physics model for tight-oil sandstone reservoirs with vertical fractures. Because of the complexities in lithology and pore structure and the anisotropic characteristics of tight-oil sandstone reservoirs, the proposed model is based on the solid components, pore connectivity, pore type, and fractures to better describe the sandstone reservoir microstructure. Using the model, we analyze the brittleness sensitivity of the elastic parameters in an anisotropic medium and establish a new brittleness index. We show the applicability of the proposed brittleness index for tight-oil sandstone reservoirs by considering the brittleness sensitivity, the rock physics response characteristics, and cross-plots. Compared with conventional brittleness indexes, the new brittleness index has high brittleness sensitivity and it is the highest in oil-bearing brittle zones with relatively high porosity. The results also suggest that the new brittleness index is much more sensitive to elastic properties variations, and thus can presumably better predict the brittleness characteristics of sweet spots in tight-oil sandstone reservoirs.展开更多
Objective： In this paper, we review the previous classic research paradigms of a mass casualty incident （MCI） systematically and reflect the medical response to the Wenchuan earthquake and Hangzhou bus tire, in ord...Objective： In this paper, we review the previous classic research paradigms of a mass casualty incident （MCI） systematically and reflect the medical response to the Wenchuan earthquake and Hangzhou bus tire, in order to outline and develop an improved research paradigm for MCI management. Methods： We searched PubMed, EMBASE China Wanfang, and China Biology Medicine （CBM） databases for relevant studies. The following key words and medical subject headings were used： ＇mass casualty incident＇, ＇MCI＇, ＇research method＇, ＇Wenchuan＇, ＇earthquake＇, ＇research paradigm＇, ＇science of surge＇, ＇surge＇, ＇surge capacity＇, and ＇vulnerability＇. Searches were performed without year or language restriction. After searching the four literature databases using the above listed key words and medical subject headings, related articles containing research paradigms of MCI, 2008 Wenchuan earthquake, July 5 bus fire, and science of surge and vulnerability were independently included by two authors. Results： The current progresses on MCI management include new golden hour, damage control philosophy, chain of survival, and three links theory. In addition, there are three evaluation methods （medical severity index （MSI）, potential injury creating event （PICE） classification, and disaster severity scale （DSS））, which can dynamically assess the MCI situations and decisions for MCI responses and can be made based on the results of such evaluations. However, the three methods only offer a retrospective evaluation of MCI and thus fail to develop a real-time assessment of MCI responses. Therefore, they cannot be used as practical guidance for decision-making during MCI. Although the theory of surge science has made great improvements, we found that a very important factor has been ignored--vulnerability, based on reflecting on the MCI response to the 2008 Wenchuan earthquake and July 5 bus fire in Hangzhou. Conclusions： This new paradigm breaks through the limitation of traditional research paradigms and will contribute to the development of a methodology for disaster research.展开更多
基金supported by the National 973 project(Nos.2014CB239006 and 2011CB202402)the National Natural Science Foundation of China(Nos.41104069 and 41274124)+1 种基金Sinopec project(No.KJWX2014-05)the Fundamental Research Funds for the Central Universities(No.R1401005A)
文摘Brittleness analysis becomes important when looking for sweet spots in tightoil sandstone reservoirs. Hence, appropriate indices are required as accurate brittleness evaluation criteria. We construct a seismic rock physics model for tight-oil sandstone reservoirs with vertical fractures. Because of the complexities in lithology and pore structure and the anisotropic characteristics of tight-oil sandstone reservoirs, the proposed model is based on the solid components, pore connectivity, pore type, and fractures to better describe the sandstone reservoir microstructure. Using the model, we analyze the brittleness sensitivity of the elastic parameters in an anisotropic medium and establish a new brittleness index. We show the applicability of the proposed brittleness index for tight-oil sandstone reservoirs by considering the brittleness sensitivity, the rock physics response characteristics, and cross-plots. Compared with conventional brittleness indexes, the new brittleness index has high brittleness sensitivity and it is the highest in oil-bearing brittle zones with relatively high porosity. The results also suggest that the new brittleness index is much more sensitive to elastic properties variations, and thus can presumably better predict the brittleness characteristics of sweet spots in tight-oil sandstone reservoirs.
基金Project supported by the Research Fund of Ministry of Health of China(No.N20080022)the Major Science and Technology Project of Zhejiang Province(No.2009C03010-3)+1 种基金the Medical Scientific Research Foundation of Zhejiang Province(No.200921012)the Educational Commission of Zhejiang Province(No.Y200908921),China
文摘Objective： In this paper, we review the previous classic research paradigms of a mass casualty incident （MCI） systematically and reflect the medical response to the Wenchuan earthquake and Hangzhou bus tire, in order to outline and develop an improved research paradigm for MCI management. Methods： We searched PubMed, EMBASE China Wanfang, and China Biology Medicine （CBM） databases for relevant studies. The following key words and medical subject headings were used： ＇mass casualty incident＇, ＇MCI＇, ＇research method＇, ＇Wenchuan＇, ＇earthquake＇, ＇research paradigm＇, ＇science of surge＇, ＇surge＇, ＇surge capacity＇, and ＇vulnerability＇. Searches were performed without year or language restriction. After searching the four literature databases using the above listed key words and medical subject headings, related articles containing research paradigms of MCI, 2008 Wenchuan earthquake, July 5 bus fire, and science of surge and vulnerability were independently included by two authors. Results： The current progresses on MCI management include new golden hour, damage control philosophy, chain of survival, and three links theory. In addition, there are three evaluation methods （medical severity index （MSI）, potential injury creating event （PICE） classification, and disaster severity scale （DSS））, which can dynamically assess the MCI situations and decisions for MCI responses and can be made based on the results of such evaluations. However, the three methods only offer a retrospective evaluation of MCI and thus fail to develop a real-time assessment of MCI responses. Therefore, they cannot be used as practical guidance for decision-making during MCI. Although the theory of surge science has made great improvements, we found that a very important factor has been ignored--vulnerability, based on reflecting on the MCI response to the 2008 Wenchuan earthquake and July 5 bus fire in Hangzhou. Conclusions： This new paradigm breaks through the limitation of traditional research paradigms and will contribute to the development of a methodology for disaster research.
