西沙更新世礁灰岩大气淡水成岩的地球化学证据

重点探讨了西琛一井更新世礁灰岩的氧碳同位素和微量元素地球化学特征及其与大气淡水成岩的关系。西琛一井全新统（０～１６．９１ｍ）基本上未成岩,矿物组分以文石和高镁方解石为主;晚更新统（１６．９１～３０．６０ｍ）出现明显方解石化,矿物组分以低镁方解石为主（平均８６％）,少量文石（平均１４％）;中—早更新统（３０．６０～１７９ｍ）几乎完全方解石化;１７９ｍ以下部分—全部白云岩化。在１６．９１～１６５ｍ,δ１８Ｏ值相对均一,而δ１３Ｃ值的变化范围很大,且两者比全新统的δ１８Ｏ和δ１３Ｃ值显著降低;在一些层位上出现δ１３Ｃ值的负偏移,向下δ１３Ｃ逐渐增大;Ｓｒ和Ｍｇ的含量亦明显降低。这一地球化学特征是大气淡水成岩的典型标志,出现δ１３Ｃ负偏移的层位代表了礁体的水上暴露面。结合岩石学特征,初步识别出１４个暴露面。１６５～１７９ｍ的δ１８Ｏ、δ１３Ｃ和Ｍｇ向下同步增加,是淡水—海水混合带的成岩产物。     

冬季太平洋海温变化对中国5月降水的影响

本文采用EOF-CCA方法研究了12-2月份北太平洋海温场与中国5月降水指数之间的相关关系。研究结果表明：12月海温与中国5月降水有较好的相关关系。赤道东太平洋和日本以东洋面的海温与中国东部地区的降水正相关，与中国华南、云南和西部地区的降水负相关。相反，东北太平洋、菲律宾以东洋面和墨西哥以西洋面的海温与中国东部地区的降水负相关，与中国华南、云南和西部地区的降水正相关。上述5个海区的太平洋前期海温对中国5月降水有影响的海温关键区。前期海温异常将影响到5月中高纬度的西风带波动和低纬西太平洋副热带高压的强度、位置、从而导致中国5月降水空间分布的异常。     

秦岭造山带佛坪基底杂岩的地质特征

综合研究表明，佛坪基底杂岩是由普遍遭受多期强烈变形变质作用和混合岩化作用的变质火山－沉积岩系和中酸性侵入岩构成的结晶杂岩系，结晶杂岩的形成年龄为22－18亿年，受强烈构造热事件改造的年龄为2亿年左右；佛坪基底杂岩经历了基底杂岩形成时期，主造山期和主造山期后3个不同演化时期的构造变形的叠加，改造，主造山期最主要的变形是在早期盖层沿其与基底的界面发生逆冲推覆构造的基础上发生热穹窿叠加变形。     

Crystallization temperature of wyomingite from Leucite Hills

Wyomingite collected from Leucite Hills is composed mainly of leucite, diopside, phlogopite, and small amounts of apatite, calcite, magnetite and rare amphibole, and is characterized by very high content of potash. Thermal experiments at atmospheric pressure indicate that the liquidus phase is always diopside with liquidus temperature of 1320 °C, and solidus temperature is about 1000 °C. Various kinds of melt inclusions are abundant in all constituent minerals. They comprise mono-phase (glass only), two-phase (gas+glass), three-phase (gas+glass+one crystalline phase) and multi-phase (gas+glass+more than two crystalline phases) inclusions. Thermal experiments have been made on these inclusions in phlogopite, diopside, and leucite in order to estimate the temperature of crystallization by homogenizing these inclusions. The results show that the crystallization of wyomingite began with formation of phlogopite accompanied by diopside at 1270 °C. Although diopside ceased crystallization at 1220 °C recurrent crystallization of phlogopite was noticed between 1120 ° and 1040 °C. Leucite crystallized out abundantly between 1250 ° and 1150 °C. Complete solidification of wyomingite occurred at about 1000 °C.     

利用鄂尔多斯盆地镇泾油田沉积微相展布与演化规律分析油田开发调整方向

油田沉积微相的展布与演化规律控制着主要有利储层的分布,因而油田开发调整方向可根据这些规律来综合考虑。镇泾油田位于鄂尔多斯盆地西南部,该油田长6油层组属于浅湖背景下的辫状河三角洲前缘沉积,其主要沉积微相包括水下分流河道、河口坝、远砂坝、席状砂、水下分流间及前三角洲泥。该区三角洲分布主要受控于两个大致平行分布的南西-北东向主河道,受基准面升降与沉积物供应的共同作用,三角洲演化呈阶段性变化,大致经历了初始发育期、繁盛发育期、间歇发育期、活化发育期等4个演化阶段,其中繁盛发育期与活化发育期的三角洲水下分流河道与河口坝砂体是主力含油储层。研究区辫状三角洲展布与演化的特点决定了今后油田开发的重点在西南部河道带两侧及东北部三角洲前缘的前端;而垂向上应以优先考虑三角洲繁盛发育期与活化发育期的叠加砂体厚度较大为原则。     

Study on Phase Behavior of CO2/Hydrocarbons in Shale Reservoirs Considering Sieving Effect and Capillary Pressure

The phase behavior of fluid is essential for predicting ultimate oil recovery and determining optimal production parameters. The pore size in shale porous media is nanopore, which causes different phase behaviors of fluid in unconventional reservoirs. Nanopores in shale media can be regard as semipermeable membrane to filter heavy components (sieving effect) in shale oil, which leads to the different distributions of fluid components and different phase behaviors. In addition, the phase behavior of fluid in nanopores can be significantly altered by large capillary pressure. In this paper, the phase behavior of fluid in shale reservoirs is investigated by a new two-phase flash algorithm considering sieving effect and capillary pressure. Firstly, membrane efficiency and capillary pressure are introduced to establish a thermodynamic equilibrium model that is solved by Rachford–Rice flash calculation and Newton–Raphson method. The capillary pressures in different pore sizes are calculated by the Young–Laplace equation. Then, the influences of sieving effect and capillary pressure on phase behavior are analyzed. The results indicate that capillary pressure can suppress the bubble point pressure of fluid in nanopores. The distributions of fluid components are different in various parts of shale media. In the unfiltered part, density and viscosity of fluid are higher. Finally, it is found that the membrane efficiency can be improved by CO₂ injection. The minimum miscibility pressure for shale oil–CO₂ system is also studied. The developed model provides a better understanding of the phase behavior of fluid in shale oil reservoirs.

     

新型地磁观测墩材料与结构的改进

海安地震台在地磁观测项目迁建过程中,对地磁观测墩体材料,尝试采用钢化玻璃替代弱磁性石材,取得良好效果,相关工作对今后地磁台站建设改造有一定借鉴作用。     

用积分法求取岩石孔隙结构特征值

针对图解法求取孔隙结构特征值使用条件严格,同时误差较大,而矩法饱和度范围又受限于试验。采用积分法求取特征值,即对孔隙半径进行积分求取特征值。积分法必须先获取孔隙半径数学表达式,即毛管压力数学模型。对毛管压力数学模型进行了探究,在双对数坐标系下推导并建立了毛管压力幂函数模型,采用最小二乘法求取模型参数,并通过对比Sami论文数据验证了推导的模型。深入分析矩法与积分法的联系可知,代入孔隙半径数学表达式即可用积分法求取岩石孔隙结构特征值。最后,对3种方法求取结果进行分析讨论,得出积分法算法严谨,更加接近真实值。这一研究加深了对岩石微观孔隙结构认识。     

以新疆于田2次M_S7.3地震为例探讨安居富民工程的减灾作用

2004年,新疆地区开展了安居工程。自开始实施以来主要分为2004~2010年的抗震安居工程和2010年至今的安居富民工程两个阶段。至今,已经整整10年。在这10年里,安居工程在抗震中起到了重要的作用。通过分析于田地区近10年地震活动背景,重点对比2008年和2014年2次于田MS7.3地震中安居工程破坏的相关参数,最终通过参数对比认为安居富民工程的建设不但降低了房屋的破坏程度,减少了经济损失和人员伤亡,而且救灾的安置成本和政府抢险救灾的投入相对减少。同时,由于安居房在地震中表现出好的抗震性能的客观鲜明的示范作用,增强了农民群众的防震减灾意识,具有重要的社会意义。