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  1. Jiangxi Ganzhong Chlorine Caustic Company aka China Jiangxi Chlor...

    Open Energy Info (EERE)

    Ganzhong Chlorine Caustic Company aka China Jiangxi Chlor Alkali Manufacturing Jump to: navigation, search Name: Jiangxi Ganzhong Chlorine & Caustic Company (aka China Jiangxi...

  2. Jiangxi Changjiang Hydropower Development Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Jiangxi Changjiang Hydropower Development Co Ltd Jump to: navigation, search Name: Jiangxi Changjiang Hydropower Development Co., Ltd. Place: Jingdezhen, Jiangxi Province, China...

  3. Jiangxi Gemei Science and Technology Inc | Open Energy Information

    Open Energy Info (EERE)

    Gemei Science and Technology Inc Jump to: navigation, search Name: Jiangxi Gemei Science and Technology Inc Place: Fuzhou, Jiangxi Province, China Sector: Solar Product: Jiangxi...

  4. Jiangxi Sornid high tech Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Sornid high tech Co Ltd Jump to: navigation, search Name: Jiangxi Sornid high-tech Co Ltd Place: Jiujiang, Jiangxi Province, China Zip: 332900 Product: PV wafer producer....

  5. Jiangxi Huahui Industrial Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Huahui Industrial Co Ltd Jump to: navigation, search Name: Jiangxi Huahui Industrial Co., Ltd. Place: Fuzhou, Jiangxi Province, China Zip: 335300 Sector: Hydro Product: China-based...

  6. Jiangxi Wugongshan Hydropower Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Wugongshan Hydropower Co Ltd Jump to: navigation, search Name: Jiangxi Wugongshan Hydropower Co., Ltd. Place: Jian City, Jiangxi Province, China Zip: 3314011 Sector: Hydro Product:...

  7. Jiangxi Quannan Hydropower Development Co Ltd | Open Energy Informatio...

    Open Energy Info (EERE)

    Quannan Hydropower Development Co Ltd Jump to: navigation, search Name: Jiangxi Quannan Hydropower Development Co. Ltd Place: Ganzhou, Jiangxi Province, China Zip: 334000 Sector:...

  8. Jiangxi Jiahua Silicon Material Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Jiahua Silicon Material Co Ltd Jump to: navigation, search Name: Jiangxi Jiahua Silicon Material Co Ltd Place: Shangrao, Jiangxi Province, China Product: A PV ingots and wafer...

  9. Jiangxi Risun Solar Energy Technology Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Risun Solar Energy Technology Co Ltd Jump to: navigation, search Name: Jiangxi Risun Solar Energy Technology Co Ltd Place: Xinyu, Jiangxi Province, China Zip: 338000 Product: A PV...

  10. Jiangxi Jinli Permanent Magnet Technology Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Jinli Permanent Magnet Technology Co Ltd Jump to: navigation, search Name: Jiangxi Jinli Permanent Magnet Technology Co Ltd Place: Ganzhou, Jiangxi Province, China Sector: Wind...

  11. Jiangxi Sinoma New Solar Materials Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Sinoma New Solar Materials Co Ltd Jump to: navigation, search Name: Jiangxi Sinoma New Solar Materials Co Ltd Place: Xinyu, Jiangxi Province, China Zip: 338032 Product:...

  12. Jiangxi Jingde Semiconductor Materials Co Ltd | Open Energy Informatio...

    Open Energy Info (EERE)

    Jingde Semiconductor Materials Co Ltd Jump to: navigation, search Name: Jiangxi Jingde Semiconductor Materials Co Ltd Place: Jingdezhen, Jiangxi Province, China Product: A Chinese...

  13. Jiangxi Province Ruijin City Liujinba Hydro Development Co Ltd...

    Open Energy Info (EERE)

    Ruijin City Liujinba Hydro Development Co Ltd Jump to: navigation, search Name: Jiangxi Province Ruijin City Liujinba Hydro Development Co,. Ltd. Place: Ruijin city, Jiangxi...

  14. Shanxi Taiyuan Zihuan Environmental Protection Technology | Open...

    Open Energy Info (EERE)

    Taiyuan Zihuan Environmental Protection Technology Jump to: navigation, search Name: Shanxi Taiyuan Zihuan Environmental Protection Technology Place: Taiyuan City, Shaanxi...

  15. Jiangxi Jiangwan Hydro Power Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Jiangwan Hydro Power Co Ltd Jump to: navigation, search Name: Jiangxi Jiangwan Hydro Power Co., Ltd. Place: Shangrao, China Zip: 344000 Sector: Hydro Product: China-based small...

  16. Jiangxi Green Avon New Energy Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Avon New Energy Co Ltd Jump to: navigation, search Name: Jiangxi Green Avon New Energy Co Ltd Place: Shanghai Municipality, China Zip: 200060 Sector: Wind energy Product: Chinese...

  17. Jiangxi Solar PV Corp JSPV aka Solar PV Corporation | Open Energy...

    Open Energy Info (EERE)

    Solar PV Corp JSPV aka Solar PV Corporation Jump to: navigation, search Name: Jiangxi Solar PV Corp (JSPV, aka Solar PV Corporation ) Place: Xinyu, Jiangxi Province, China Zip:...

  18. Advanced clean combustion technology in Shanxi province

    SciTech Connect (OSTI)

    Xie, K.-C.

    2004-07-01

    Biomass energy resources in China are first described, along with biomass gasification R & D now underway. In Shanxi province biomass and other regenerative energy is relatively little used but coal resources are large. Hence Shanxi is mainly developing clean coal technology to meet its economic and environmental protection requirements. Clean combustion research at Taiyuan University of Technology includes cofiring of coal and RDF in FBC, gas purification and adsorption, fundamentals of plasma-aided coal pyrolysis and gasification and coal derived liquid fuels from synthesis gas. 5 refs.

  19. Shanxi Milestone Biomass Energy Development Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Milestone Biomass Energy Development Co Ltd Jump to: navigation, search Name: Shanxi Milestone Biomass Energy Development Co Ltd Place: China Sector: Biomass Product: China-based...

  20. Shanxi Zhangze Power Inner Mongolia Subsidiary | Open Energy...

    Open Energy Info (EERE)

    Zhangze Power Inner Mongolia Subsidiary Jump to: navigation, search Name: Shanxi Zhangze Power Inner Mongolia Subsidiary Place: Inner Mongolia Autonomous Region, China Sector: Wind...

  1. Jiangxi Ganneng Huaji New Energy Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Ganneng Huaji New Energy Co Ltd Place: Nanchang, Jiangxi Province, China Product: A-Si thin film PV cell manufacturer in China. Coordinates: 28.6712, 115.889221 Show Map...

  2. Geothermal Resources Development in Tibet, China | Open Energy...

    Open Energy Info (EERE)

    navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Geothermal Resources Development in Tibet, China Abstract Tibet is located in the eastern...

  3. ShanXi Xin Tong Intelligence Technical Co Ltd | Open Energy Informatio...

    Open Energy Info (EERE)

    materials,new materials,radiating heating system of floors,studiums constructions,tyres,arts and crafts,professional services. References: ShanXi Xin-Tong Intelligence Technical Co...

  4. Jiangxi Ganneng Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Province, quoted in Shenzhen Stock Exchange and recently announced that they would build a thin-film PV cell JV factory with a designed capacity of 50MW. Coordinates:...

  5. Zhonghuite PV Technology Co | Open Energy Information

    Open Energy Info (EERE)

    Zhonghuite PV Technology Co Jump to: navigation, search Name: Zhonghuite PV Technology Co Place: Jiangxi Province, China Sector: Solar Product: Jiangxi-based solar project...

  6. Zhongke Photovoltaic Material Technology Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Zhongke Photovoltaic Material Technology Co Ltd Jump to: navigation, search Name: Zhongke Photovoltaic Material Technology Co Ltd Place: Pingxiang, Jiangxi Province, China Product:...

  7. Yangxian Longsheng Hydropower Development Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Yangxian Longsheng Hydropower Development Co Ltd Jump to: navigation, search Name: Yangxian Longsheng Hydropower Development Co., Ltd. Place: Hanzhong, Jiangxi Province, China Zip:...

  8. Jian Gongge Hydropower Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Jian Gongge Hydropower Co Ltd Jump to: navigation, search Name: Jian Gongge Hydropower Co., Ltd. Place: Jian, Jiangxi Province, China Zip: 343100 Sector: Hydro Product: China-based...

  9. Anfu Guanshan Hydropower Development Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Anfu Guanshan Hydropower Development Co Ltd Jump to: navigation, search Name: Anfu Guanshan Hydropower Development Co.,Ltd Place: Jiangxi Province, China Zip: 343009 Sector: Hydro...

  10. Zixi Sanjiang Hydropower Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Zixi Sanjiang Hydropower Co Ltd Jump to: navigation, search Name: Zixi Sanjiang Hydropower Co Ltd Place: Fuzhou, Jiangxi Province, China Zip: 335300 Sector: Hydro Product:...

  11. Jinggangshan Longgan Hydropower Development Co Ltd | Open Energy...

    Open Energy Info (EERE)

    Jinggangshan Longgan Hydropower Development Co Ltd Jump to: navigation, search Name: Jinggangshan Longgan Hydropower Development Co., Ltd. Place: Jian, Jiangxi Province, China Zip:...

  12. Observed high-altitude warming and snow cover retreat over Tibet and the Himalayas enhanced by black carbon aerosols

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, Y.; Ramanathan, V.; Washington, W. M.

    2015-07-10

    Himalayan mountain glaciers and the snowpack over the Tibetan Plateau provide the headwater of several major rivers in Asia. In-situ observations of snow cover fraction since the 1960s suggest that the snow pack in the region have retreated significantly, accompanied by a surface warming of 2–2.5 °C observed over the peak altitudes (5000 m). Using a high-resolution ocean–atmosphere global climate model and an observationally constrained black carbon (BC) aerosol forcing, we attribute the observed altitude dependence of the warming trends as well as the spatial pattern of reductions in snow depths and snow cover fraction to various anthropogenic factors. Atmore »the Tibetan Plateau altitudes, the increase of atmospheric CO2 concentration exerted a warming of 1.7 °C, BC 1.3 °C where as cooling aerosols cause about 0.7 °C cooling, bringing the net simulated warming consistent with the anomalously large observed warming. We therefore conclude that BC together with CO2 has contributed to the snow retreat trends. Especially, BC increase is the major factor in the strong elevation dependence of the observed surface warming. The atmospheric warming by BC as well as its surface darkening of snow are coupled with the positive snow albedo feedbacks to account for the disproportionately large role of BC in high-elevation regions. These findings reveal that BC impact needs to be properly accounted for in future regional climate projections, in particular on high-altitude cryosphere.« less

  13. Shaanxi Green Energy | Open Energy Information

    Open Energy Info (EERE)

    Energy Jump to: navigation, search Name: Shaanxi Green Energy Place: Xianyang, Shanxi Province, China Sector: Geothermal energy Product: A project SPV company which operates a...

  14. Wutai Gengzhen Hydropower Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Wutai Gengzhen Hydropower Co Ltd Jump to: navigation, search Name: Wutai Gengzhen Hydropower Co., Ltd. Place: Shanxi Province, China Zip: 35512 Sector: Hydro Product: China-based...

  15. Yangcheng Motan Hydropower Development Co Ltd | Open Energy Informatio...

    Open Energy Info (EERE)

    Yangcheng Motan Hydropower Development Co Ltd Jump to: navigation, search Name: Yangcheng Motan Hydropower Development Co., Ltd. Place: Shanxi Province, China Zip: 48100 Sector:...

  16. Dingxiang Lingzidi Hydropower Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Dingxiang Lingzidi Hydropower Co Ltd Jump to: navigation, search Name: Dingxiang Lingzidi Hydropower Co., Ltd. Place: Shanxi Province, China Zip: 35407 Sector: Hydro Product:...

  17. Datong Fuqiao Waste Incineration Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Datong Fuqiao Waste Incineration Co Ltd Jump to: navigation, search Name: Datong Fuqiao Waste Incineration Co Ltd Place: Datong, Shanxi Province, China Zip: 37008 Product:...

  18. Huichang Bai exia Hydro Power Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Huichang Bai exia Hydro Power Co Ltd Jump to: navigation, search Name: Huichang Bai'exia Hydro Power Co., Ltd Place: Jiangxi Province, China Zip: 342600 Sector: Hydro Product:...

  19. Lu an Group | Open Energy Information

    Open Energy Info (EERE)

    Name: Lu'an Group Place: Changzhi, Shanxi Province, China Zip: 46204 Product: A Chinese chemical and energy enterprise specialised in coal. Coordinates: 36.468231, 112.82312...

  20. The Resource Potential of Natural Gas Hydrates

    Energy Savers [EERE]

    International Gas Hydrate Research March 2014 International Gas Hydrate Projects - Overview Gas Hydrate Field Projects * MH21 - Japan * UBGH-1 & UBGH-2 - Republic of Korea * GMGS-1 & GMGS-2, Qinghai-Tibet Projects - P.R. China * NGHP01 - India * Arctic Permafrost Gas Hydrate Testing -Mallik & Mackenzie Delta - Canada -Alaska North Slope (Statoil and JOGMEC interest) Summary and Recommendations Presentation Outline Contents 4. Methane Hydrate Research Drilling Expeditions 4.1. ODP Leg

  1. Experimental study on NOx emission and unburnt carbon of a radial biased swirl burner for coal combustion

    SciTech Connect (OSTI)

    Shan Xue; Shi'en Hui; Qulan Zhou; Tongmo Xu

    2009-07-15

    Pilot tests were carried out on a 1 MW thermal pulverized coal fired testing furnace. Symmetrical combustion was implemented by use of two whirl burners with dual air adjustment. The burnout air device was installed in various places at the top of the main burner, which consists of a primary air pipe with a varying cross-section and an impact ring. In the primary air pipe, the air pulverized coal (PC) stream was separated into a whirling stream that was thick inside and thin outside, thus realizing the thin-thick distribution at the burner nozzle in the radial direction. From the comparative combustion tests of three coals with relatively great characteristic differences, Shaanbei Shenhua high rank bituminous coal (SH coal), Shanxi Hejin low rank bituminous coal (HJ coal), and Shanxi Changzhi meager coal (CZ coal), were obtained such test results as the primary air ratio, inner secondary air ratio, outer secondary air ratio, impact of the change of outer secondary air, change of the relative position for the layout of burnout air, change of the swirling intensity of the primary air and secondary air, etc., on the NOx emission, and unburnt carbon content in fly ash (CFA). At the same time, the relationship between the NOx emission and burnout ratio and affecting factors of the corresponding test items on the combustion stability and economic results were also acquired. The results may provide a vital guiding significance to engineering designs and practical applications. According to the experimental results, the influence of each individual parameter on NOx formation and unburned carbon in fly ash agrees well with the existing literature. In this study, the influences of various combinations of these parameters are also examined, thus providing some reference for the design of the radial biased swirl burner, the configuration of the furnace, and the distribution of the air. 23 refs., 14 figs., 2 tabs.

  2. Current trends in non-accelerator particle physics: 1, Neutrino mass and oscillation. 2, High energy neutrino astrophysics. 3, Detection of dark matter. 4, Search for strange quark matter. 5, Magnetic monopole searches

    SciTech Connect (OSTI)

    He, Yudong |

    1995-07-01

    This report is a compilation of papers reflecting current trends in non-accelerator particle physics, corresponding to talks that its author was invited to present at the Workshop on Tibet Cosmic Ray Experiment and Related Physics Topics held in Beijing, China, April 4--13, 1995. The papers are entitled `Neutrino Mass and Oscillation`, `High Energy Neutrino Astrophysics`, `Detection of Dark Matter`, `Search for Strange Quark Matter`, and `Magnetic Monopole Searches`. The report is introduced by a survey of the field and a brief description of each of the author`s papers.

  3. Crustal structure of mountain belts and basins: Industry and academic collaboration at Cornell

    SciTech Connect (OSTI)

    Allmendinger, R.; Barazangi, M.; Brown, L. [Cornell Univ., Ithaca, NY (United States)] [and others

    1995-08-01

    Interdisciplinary investigations of the large-scale structure and evolution of key basins and orogenic belts around the world are the focal point of academic-industry interaction at Cornell. Ongoing and new initiatives with significant industry involvement include: Project INDEPTH (Interdisciplinary Deep Profiling of Tibet and the Himalayas), a multinational effort to delineate deep structure across the type example of active continent-continent collision. 300 km of deep reflection profiling was collected across the Himalaya: and southern Tibet Plateau in 1992 and 1994. CAP (Cornell Andes Project), a long-standing interdisciplinary effort to understand the structure and evolution of the Andes, with a focus on Argentina, Chile and Bolivia. A deep reflection profile is tentatively planned for 1997. Intra-plate Orogeny in the Middle East and North Africa is the focus of multidisciplinary regional syntheses of existing seismic reflection and other databases in Syria (Palmyrides)and Morocco (Atlas), with an emphasis on reactivation and inversion tectonics. Project URSEIS (Urals Reflection Seismic Experiment and Integrated Studies) is a collaboration with EUROPROBE to collect 500 km of vibroseis and dynamite deep reflection profiling across the southern Urals in 1995. Project CRATON, an element in COCORP`s systematic exploration of the continental US, is a nascent multi-disciplinary effort to understand the buried craton of the central US and the basins built upon it. Global Basins Research Network (GBRN) is a diversified observational and computational effort to image and model the movement of pore fluids in detail and on a regional scale for a producing oil structure in the Gulf of Mexico.

  4. Changes in Moisture Flux over the Tibetan Plateau during 1979-2011: Insights from a High Resolution Simulation

    SciTech Connect (OSTI)

    Gao, Yanhong; Leung, Lai-Yung R.; Zhang, Yongxin; Cuo, Lan

    2015-05-15

    Net precipitation (precipitation minus evapotranspiration, P-E) changes between 1979 and 2011 from a high resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibet Plateau (TP) and compared to the global land data assimilation system (GLDAS) product. The high resolution simulation better resolves precipitation changes than its coarse resolution forcing, which contributes dominantly to the improved P-E change in the regional simulation compared to the global reanalysis. Hence, the former may provide better insights about the drivers of P-E changes. The mechanism behind the P-E changes is explored by decomposing the column integrated moisture flux convergence into thermodynamic, dynamic, and transient eddy components. High-resolution climate simulation improves the spatial pattern of P-E changes over the best available global reanalysis. High-resolution climate simulation also facilitates new and substantial findings regarding the role of thermodynamics and transient eddies in P-E changes reflected in observed changes in major river basins fed by runoff from the TP. The analysis revealed the contrasting convergence/divergence changes between the northwestern and southeastern TP and feedback through latent heat release as an important mechanism leading to the mean P-E changes in the TP.

  5. Changes in Moisture Flux Over the Tibetan Plateau During 1979-2011: Insights from a High Resolution Simulation

    SciTech Connect (OSTI)

    Gao, Yanhong; Leung, Lai-Yung R.; Zhang, Yongxin; Cuo, Lan

    2015-05-01

    Net precipitation (precipitation minus evapotranspiration, P-E) changes from a high resolution regional climate simulation and its reanalysis forcing are analyzed over the Tibet Plateau (TP) and compared to the global land data assimilation system (GLDAS) product. The mechanism behind the P-E changes is explored by decomposing the column integrated moisture flux convergence into thermodynamic, dynamic, and transient eddy components. High-resolution climate simulation improves the spatial pattern of P-E changes over the best available global reanalysis. Improvement in simulating precipitation changes at high elevations contributes dominantly to the improved P-E changes. High-resolution climate simulation also facilitates new and substantial findings regarding the role of thermodynamics and transient eddies in P-E changes reflected in observed changes in major river basins fed by runoff from the TP. The analysis revealed the contrasting convergence/divergence changes between the northwestern and southeastern TP and feedback through latent heat release as an important mechanism leading to the mean P-E changes in the TP.

  6. Lithospheric Thickness Modeled from Long Period Surface Wave Dispersion

    SciTech Connect (OSTI)

    Pasyanos, M E

    2008-05-15

    The behavior of surface waves at long periods is indicative of subcrustal velocity structure. Using recently published dispersion models, we invert surface wave group velocities for lithospheric structure, including lithospheric thickness, over much of the Eastern Hemisphere, encompassing Eurasia, Africa, and the Indian Ocean. Thicker lithosphere under Precambrian shields and platforms are clearly observed, not only under the large cratons (West Africa, Congo, Baltic, Russia, Siberia, India), but also under smaller blocks like the Tarim Basin and Yangtze craton. In contrast, it is found that remobilized Precambrian structures like the Saharan Shield and Sino-Korean Paraplatform do not have well-established lithospheric keels. The thinnest lithospheric thickness is found under oceanic and continental rifts, as well as along convergence zones. We compare our results to thermal models of continental lithosphere, lithospheric cooling models of oceanic lithosphere, lithosphere-asthenosphere boundary (LAB) estimates from S-wave receiver functions, and velocity variations of global tomography models. In addition to comparing results for the broad region, we examine in detail the regions of Central Africa, Siberia, and Tibet. While there are clear differences in the various estimates, overall the results are generally consistent. Inconsistencies between the estimates may be due to a variety of reasons including lateral and depth resolution differences and the comparison of what may be different lithospheric features.

  7. Climate-Energy Nexus

    SciTech Connect (OSTI)

    Gary Sayler; Randall Gentry; Jie Zhuang

    2010-07-01

    The 140-page published proceedings of the workshop include individual articles and PowerPoint slides for all workshop presentations. The proceedings also contain pertinent background information on the China-US Joint Research Center, partnering organizations, and workshop goals and objectives. Overall, the workshop increased the understanding of the impacts of climate change on energy use and renewable energy production as well as the complex relationships among land use, energy production, and ecological restoration. The workshop served as an international platform for scientists and students of different research backgrounds to develop a unified perspective on energy and climate relationships. Such understanding will benefit future cooperation between China and the US in mitigating global climate change. The workshop’s agenda, which is highly interdisciplinary, explored many potential opportunities for international collaboration in ecosystem management, climate modeling, greenhouse gas emissions, and bioenergy sustainability. International research groups have been suggested in the areas of genomes and biotechnology of energy plants, sustainable management of soil and water resources, carbon sequestration, and microbial processes for ecological cycles. The project has attracted considerable attention from institutes beyond the China-US Joint Research Center partners, and several of them (such as Institute of Qing-Tibet Plateau Research, Institute of Soil and Water Conservation, Institute of Applied Ecology, CAS) have expressed interest in joining the partnership. In addition, the workshop played a significant role in facilitating establishment of private-public partnerships between government and private bioenergy companies (such as L.R. Shugarts and Associates, Inc.), including seed providers (Blade Energy Crops, Thousand Oaks, CA), pilot demonstration projects at coal-producing cities (e.g., Huaibei, Anhui province, China), and the development of methodology for assessment of the sustainable production of biofuels (such as life-cycle analysis, sustainability metrics, and land-use policy). Establishment of two US-China scientific research networks in the area of bioenergy and environmental science is a significant result of the workshop.

  8. PROGRESS TOWARDS NEXT GENERATION, WAVEFORM BASED THREE-DIMENSIONAL MODELS AND METRICS TO IMPROVE NUCLEAR EXPLOSION MONITORING IN THE MIDDLE EAST

    SciTech Connect (OSTI)

    Savage, B; Peter, D; Covellone, B; Rodgers, A; Tromp, J

    2009-07-02

    Efforts to update current wave speed models of the Middle East require a thoroughly tested database of sources and recordings. Recordings of seismic waves traversing the region from Tibet to the Red Sea will be the principal metric in guiding improvements to the current wave speed model. Precise characterizations of the earthquakes, specifically depths and faulting mechanisms, are essential to avoid mapping source errors into the refined wave speed model. Errors associated with the source are manifested in amplitude and phase changes. Source depths and paths near nodal planes are particularly error prone as small changes may severely affect the resulting wavefield. Once sources are quantified, regions requiring refinement will be highlighted using adjoint tomography methods based on spectral element simulations [Komatitsch and Tromp (1999)]. An initial database of 250 regional Middle Eastern events from 1990-2007, was inverted for depth and focal mechanism using teleseismic arrivals [Kikuchi and Kanamori (1982)] and regional surface and body waves [Zhao and Helmberger (1994)]. From this initial database, we reinterpreted a large, well recorded subset of 201 events through a direct comparison between data and synthetics based upon a centroid moment tensor inversion [Liu et al. (2004)]. Evaluation was done using both a 1D reference model [Dziewonski and Anderson (1981)] at periods greater than 80 seconds and a 3D model [Kustowski et al. (2008)] at periods of 25 seconds and longer. The final source reinterpretations will be within the 3D model, as this is the initial starting point for the adjoint tomography. Transitioning from a 1D to 3D wave speed model shows dramatic improvements when comparisons are done at shorter periods, (25 s). Synthetics from the 1D model were created through mode summations while those from the 3D simulations were created using the spectral element method. To further assess errors in source depth and focal mechanism, comparisons between the three methods were made. These comparisons help to identify problematic stations and sources which may bias the final solution. Estimates of standard errors were generated for each event's source depth and focal mechanism to identify poorly constrained events. A final, well characterized set of sources and stations will be then used to iteratively improve the wave speed model of the Middle East. After a few iterations during the adjoint inversion process, the sources will be reexamined and relocated to further reduce mapping of source errors into structural features. Finally, efforts continue in developing the infrastructure required to 'quickly' generate event kernels at the n-th iteration and invert for a new, (n+1)-th, wave speed model of the Middle East. While development of the infrastructure proceeds, initial tests using a limited number of events shows the 3D model, while showing vast improvement compared to the 1D model, still requires substantial modifications. Employing our new, full source set and iterating the adjoint inversions at successively shorter periods will lead to significant changes and refined wave speed structures of the Middle East.