珊瑚礁地层钻探取心技术研究及应用

人工吹填珊瑚岛礁地层结构比较特殊,以珊瑚砂和珊瑚碎屑为主,取心和成孔难度较大。以南海某岛礁地质钻探取心工程实践为例,针对地层岩性特点,采用一系列对应技术措施：上部松散或弱胶结砂砾层采取跟管钻进和无水干钻取心技术;礁灰岩全漏失地层设计了一套掏砂钻具进行掏砂,确保井眼干净;软硬互层采用超前侧喷钻头;粉砂质地层采取小口径钻具无水干钻取心技术等。该技术在18个钻孔实施中取得了良好的效果,可为后续珊瑚礁地层钻探取心提供借鉴。     

汶川Ms 8.0地震极重灾区的经济韧性测度及恢复效率

揭示灾后经济发展状态和恢复过程,按照灾区经济韧性科学制定灾后经济重建的调控政策与恢复手段,对增强灾害防范与系统应对能力具有重要意义。以汶川地震极重灾区为案例,基于长时序社会经济面板数据与ARIMA模型,测算灾区经济韧性指数,并运用改进的规模报酬可变DEA模型、Malmquist生产率指数分析灾后年际经济恢复效率及影响效应。结果显示：① 汶川地震极重灾区经济韧性指数为0.877,地震导致灾区短期经济衰退,但2年内恢复至震前水平,工业经济韧性低于农业和服务业。② 受灾当年灾区经济恢复综合效率为0.603,其中,平原丘陵区综合效率、纯技术效率、规模效率均显著优于高原山地区。③ 灾后全要素生产率的年际波动强烈,经济恢复效率显著下降造成短期经济衰退,灾后2年TFP指数下降33.7%和15.2%后恢复至稳态。④ 灾后恢复效率显著下降主因为技术变动因素,而生产体系更新程度决定了灾后经济韧性。随着灾后经济恢复的规模收益下降,灾区经济恢复主要依赖纯技术效率,提升纯技术效率是保持灾后经济长期增长的动力。可见,针对重建自然条件和经济发展阶段的差异性,灾区当地需积极进行经济结构调整和再适应,同时,通过生产体系更新提升技术进步水平,以发挥灾后大规模资金、设施、人力等要素投入的规模效应,从而增强应对灾害冲击的经济韧性与恢复效率。     

安徽巢湖北部地区下三叠统和龙山组微生物岩及其意义

巢湖北部地区下三叠统和龙山组(Smithian亚阶中上段)含有特征明显的微生物岩.微生物岩包含微生物席和叠层石两种类型,其中最为丰富的类型是以蓝藻为主.该组微生物岩的普遍发育以及宏体化石组合的分布特征表明,和龙山组微生物岩可能是早三叠世生态环境开始改善、生物开始复苏的标志.微生物岩及微生物群落特征表明,该组很可能沉积于...     

新疆塔河油田C区奥陶系油藏一次采收率的确定

塔河油田C区是近年在油气勘探史上的又一重大突破。该区主要储、产油气层为下奥陶统,其储层属于潜山碳酸盐岩储层类型,具有较强的非均质性。塔河油田C区奥陶系油藏正处于开发初期阶段,动态资料尚少,根据油田地质情况、油藏类型及拥有的实际资料特征,笔者采用经验公式法、表格估算法及类比法3种方法对采收率进行评价。     

“The Community Helped Me:” Community Cohesion and Environmental Concerns in Personal Assessments of Post-Disaster Recovery

Abstract

This study investigates long-term appraisals of community recovery after a major environmental disaster. Specifically, we conducted a survey of 351 individuals living in coastal counties in Alabama and Florida on the five-year anniversary of the Deepwater Horizon oil spill. Using mixed methods that combined content analysis and ordinary least squares regression, we find that residents who believe they live in a community where neighbors help each other are more likely to see their communities as recovering. Conversely, reporting major effects from environmental problems, like lost fishing income, reduces perceptions of community recovery. Five years after the oil spill a majority of respondents saw little economic recovery and almost half perceived low environmental recovery. This reflects the importance of the environment to the long-term health and success of areas dependent on natural resources. It also suggests the need for directing funding toward community-level programs and preserving shared natural resources post-disaster.     

A watershed rainfall data recovery approach with application to distributed hydrological models

Watershed areal rainfall estimation, which is one of the most important and fundamental aspects in hydrological forecasting and various kinds of catchment‐scale hydrological models, is widely used in the analysis of hydrological regime change, and its precision has a direct influence on the accuracy of hydrological forecasting and hydrological simulation. In China, it is difficult to obtain the watershed areal rainfall estimate with reliable precision and avoid the phenomenon of ‘the same effect of different parameters’ because of the low density of the rain gauge network. Therefore, a watershed rainfall data recovery approach of improving the precision of watershed areal rainfall estimation is proposed here. This approach is to build new observatories, establish the time–space relations of rainfall between newly built observatories and previously built observatories in a relatively short interval and then recover the rainfall data of newly built observatories prior to their construction through simulating the relations over a longer time. As a result, watershed rainfall information could be elaborated to improve the precision of watershed areal rainfall estimate and avoid the phenomenon of ‘the same effect of different parameters’ to a certain degree in the process of hydrological simulation. The approach is used in the hydrological simulation of Hali River catchment. In combination with the Soil Water Assessment Tool model, a better result can be obtained in the hydrological simulation. Therefore, the approach can be used in other similar catchments. Copyright © 2011 John Wiley & Sons, Ltd.     

Meta‐analysis of field‐saturated hydraulic conductivity recovery following wildland fire: Applications for hydrologic model parameterization and resilience assessment

Hydrologic recovery after wildfire is critical for restoring the ecosystem services of protecting of human lives and infrastructure from hazards and delivering water supply of sufficient quality and quantity. Recovery of soil‐hydraulic properties, such as field‐saturated hydraulic conductivity (K_fs), is a key factor for assessing the duration of watershed‐scale flash flood and debris flow risks after wildfire. Despite the crucial role of K_fs in parameterizing numerical hydrologic models to predict the magnitude of postwildfire run‐off and erosion, existing quantitative relations to predict K_fs recovery with time since wildfire are lacking. Here, we conduct meta‐analyses of 5 datasets from the literature that measure or estimate K_fs with time since wildfire for longer than 3‐year duration. The meta‐analyses focus on fitting 2 quantitative relations (linear and non‐linear logistic) to explain trends in K_fs temporal recovery. The 2 relations adequately described temporal recovery except for 1 site where macropore flow dominated infiltration and K_fs recovery. This work also suggests that K_fs can have low hydrologic resistance (large postfire changes), and moderate to high hydrologic stability (recovery time relative to disturbance recurrence interval) and resilience (recovery of hydrologic function and provision of ecosystem services). Future K_fs relations could more explicitly incorporate processes such as soil‐water repellency, ground cover and soil structure regeneration, macropore recovery, and vegetation regrowth.     

27.3-day and Average 13.6-day Periodic Oscillations in the Earth’s Rotation Rate and Atmospheric Pressure Fields Due to Celestial Gravitation Forcing

Variation in length of day of the Earth (LOD, equivalent to the Earth’s rotation rate) versus change in atmospheric geopotential height fields and astronomical parameters were analyzed for the years 1962-2006. This revealed that there is a 27.3-day and an average 13.6-day periodic oscillation in LOD and atmospheric pressure fields following lunar revolution around the Earth. Accompanying the alternating change in celestial gravitation forcing on the Earth and its atmosphere, the Earth’s LOD changes from minimum to maximum, then to minimum, and the atmospheric geopotential height fields in the tropics oscillate from low to high, then to low. The 27.3-day and average 13.6-day periodic atmospheric oscillation in the tropics is proposed to be a type of strong atmospheric tide, excited by celestial gravitation forcing. A formula for a Tidal Index was derived to estimate the strength of the celestial gravitation forcing, and a high degree of correlation was found between the Tidal Index determined by astronomical parameters, LOD, and atmospheric geopotential height. The reason for the atmospheric tide is periodic departure of the lunar orbit from the celestial equator during lunar revolution around the Earth. The alternating asymmetric change in celestial gravitation forcing on the Earth and its atmosphere produces a "modulation" to the change in the Earth’s LOD and atmospheric pressure fields.     

老挝巴勉岩金矿钻探施工实践

境外钻探施工不但有施工技术方面的难题,更重要的是会遇到境外的施工环境、语言等诸多让人担忧让人却步的从未接触过的问题。介绍了在老挝巴勉岩金矿进行钻探施工遇到的各种难题及解决办法。     

螺旋钻进模拟月壤过程的热场分析

介绍了一种新型的月壤钻具,为了了解新型螺旋钻具在钻进模拟月壤过程中的热场分布,优化了钻进过程参数,通过理论计算建立了钻进过程热场分布模型,并通过实验进行了验证,同时进行了热电偶测温实验.测温结果显示,所建立的模型较好地符合钻进过程的温度分布;在相同的条件下,钻进过程的温度随着转速的降低而升高.计算分析和实验结果表明:月...