莫116井区水平井钻井设计优化与应用

莫116井区在水平井钻井施工过程中,面临着“缩、卡、塌、漏、喷、硬”等难题,为避免井下复杂事故、缩减钻井周期、降低作业风险,在该区开展了水平井优化设计与轨迹优化控制技术研究工作。通过井区已钻井资料论证分析,针对性地对井身结构和井眼轨迹控制提出了优化方案;根据前期实钻情况和钻柱力学分析,优化了水平井钻井钻具组合和钻井参数;通过优化泥浆体系,解决定向作业井段了井壁稳定性差、定向施工摩阻大、粘附卡钻几率高等问题。通过对上述研究成果的现场应用,实现了水平井优快钻井目标,二开定向段和三开井段平均机械钻速相比优化前水平分别提高27%、30%,其中M614等井实现了“一趟钻”完成了水平段钻进目标。     

浙江近海横带髭鲷(Hapalogenys mucronatus)表型性状与体重的通径分析及曲线拟合

横带髭鲷(Hapalogenys mucronatus)是我国优质近海岛礁性鱼类,具有较高的经济、营养和观赏价值,有着良好的发展前景。为研究横带髭鲷野生群体的表型性状对体重的影响效果,测定了全长(X₁)、体长(X₂)、头长(X₃)、躯干长(X₄)、尾部长(X₅)、眼径(X₆)、体高(X₇)、尾柄高(X₈)、体宽(X₉)、眼间距(X₁₀)10个表型性状及体重(Y),利用相关分析、通径分析、回归分析等方法探究了表型性状对体重的影响,并建立多元回归方程,分别以列入回归方程的4个表型性状为自变量,体重为因变量进行曲线模型拟合,筛选出最优拟合模型。结果表明,体重的变异系数最大,而表型性状则相对较小。横带髭鲷各性状之间均呈现极显著正相关关系(P<0.01),全长与体长的相关系数(0.967)最大,体高与体重的相关系数(0.958)次之。通径分析发现体高对体重的直接作用最大(0...     

Anastamosing channels in the lower Neches River valley,Texas

Active and semi‐active anastomosing Holocene channels upstream of the delta in the lower valley of the meandering Neches River in southeast Texas represent several morphologically distinct and hydrologically independent channel systems. These appear to have a common origin as multi‐thread crevasse channels strongly influenced by antecedent morphology. Levee breaching leads to steeper cross‐valley flows toward floodplain basins associated with Pleistocene meander scars, creating multi‐thread channels that persist due to additional tributary contributions and ground water inputs. Results are consistent with the notion of plural systems where main channels, tributaries, and sub‐channels may have different morphologies and hydrogeomorphic functions. The adjacent Trinity and Sabine Rivers have similar environmental controls, yet the Trinity lacks evidence of extensive anastomosing channels on its floodplain, and those of the Sabine appear to be of different origin. The paper highlights the effects of geographical and historical contingency and hydrological idiosyncrasy. Copyright © 2014 John Wiley & Sons, Ltd.     

Expression of strain and rotation tensor in geodetic coordinates

In this paper, unit moving trihedron is first constructed for a point on the surface of a revolution ellipsoid. Via translation, the origin of the trihedron coincides with that of Cartesian coordinates established at the center of the ellipsoid, and then through two coordinate rotations, the trihedron completely coincides with the Cartesian coordi-nates. Transformation formulae between the moving trihedron and unit Cartesian coordinate frameworks as well as transformation of point displacement between two unit coordinate frameworks are presented. Based on the above transformation formulae between two different coordinate frameworks, due to the fact that the displacement and moving trihedron of the point are both functions of the geodetic coordinates, components in the corresponding axis for differential of displacement vector and geodetic curves arc differential at the point in geodetic system can be obtained through complicated derivation. Displacement gradient matrix at the point in geodetic system is also given. Finally, expressions of strain and rotation tensor in geodetic coordinates are presented. Geometric meanings of the rotation tensor are explained in detail. The intrinsic relationship between strain tensors of sphere and ellip-soid are also discussed.     

生命线工程网络抗震可靠性算法研究

现代城市的迅速发展对生命线工程系统依赖性逐渐增强。地震后生命线工程系统的性能直接决定了灾后生活和生产的恢复以及抢险工作的进行,因此对生命线工程系统进行地震作用下的可靠性分析具有十分重要的意义。本文中主要介绍2种求解大型网络抗震可靠度算法———最小路递推分解算法和最小割递推分解算法。在此基础上,利用这2种算法对沈阳市供气系统进行了分析。研究结果表明,合理选择使用这2种算法可以有效的进行不同地震烈度条件下的大型生命线工程系统的可靠性分析。     

天山南侧喀什地区冰雹潜势预报及预警指标的研究

利用2008-2017年5~8月天山南侧喀什地区气象台站观测记录、人工防雹作业点记录、灾害调查等资料,喀什探空站08时、20时探空资料,喀什雷达探测资料及其基数据反演产品,对冰雹的年分布、月分布及日变化特征进行了分析,归纳出冰雹云的雷达回波特征及移动路径,依据百分位数方法确定了以0℃层高度、-20℃层高度、冻结层厚度、全总指数、杰弗逊指数、K指数、沙氏指数为代表的冰雹预报指标,以及以回波顶高及其与当日0℃层高度差、40~50 dBZ回波高度及其与当日0℃层高度差、组合反射率、垂直积分液态水含量为代表的雷达特征预警指标。     

Petrogenetic grid for ultrahigh-pressure metamorphism in the model system CaO-MgO-SiO2-CO2-H2O

Abstract Petrogenetic grids for ultrahigh-pressure (UHP) metamorphism were calculated at different X_co2 conditions in the model system CaO-MgO-SiO₂-CO₂-H₂O involving coesite (Co), diopside (Di), dolomite (Do), enstatite (En), forsterite (Fo), magnesite (Ms), quartz (Qz), talc (Tc), tremolite (Tr) using a published internally consistent thermodynamic data set. Two P-T grids at X_co2= 0.01 and 0.5 are described. In the calculated P-T grid at X_co2= 0.01, four out of 10 stable invariant points, Co-En-Ms-Tc, Co-Di-En-Tc-Tr, Co-Di-Ms-Tc-Tr and Di-En-Ms-Tc-Tr lie within the stability field of coesite. If the fluid phase has X_co2= 0.5, no invariant point is stable under UHP conditions. Some magnesite-bearing assemblages are stabilized by the following three reactions: Di + Ms = Do + Fo + CO₂, Ms + Tr = Do + Fo + CO₂+ H₂O and Ms + Tc = Fo+ CO₂+ H₂O at X_co2= 0.01 and by reaction Ms + Tc = Fo + CO₂+ H₂O together with these three at X_co2= 0.5. Ten possible UHP assemblages for mafic and ultramafic compositions at very low X_co2 conditions include the following: Co-Do-Ms, Co-Di-Ms, Co-Di-Tc, Di-Ms-Tc, Di-En-Tc-, Di-En-Ms, Co-Di-En, Di-En-Fo, Di-Fo-Ms, Di-Do-Fo. Among them, talc-bearing assemblages are restricted to X_co2 < 0.02 and their high-P limit is 31.7 kb (749°C) at X_co2= 0.01. Dolomite-magnesite-silica assemblages have large P-T stability fields even if X_co2 is as low as 0.1, and could occur in cold subduction zones with very low geothermal gradients. Reported UHP coesite-dolomite assemblage is restricted only to a calc-silicate rock interlayered with marble where X_co2 is relatively higher; no such assemblage appears for mafic and ultramafic rocks with low X_co2 evidenced by the occurrence of diopside (or omphacite) at the expense of dolomite + coesite. The effect of X_co2 on the stability of coesite-dolomite-magnesite, diopside-enstatite-magnesite, diopside-talc assemblages is examined and the occurrence of coesite-dolomite, magnesite-bearing and talc-bearing assemblages in the Dabie UHP rocks are interpreted by employing the calculated P-T grids.     

Phase Equilibria of Hornblende-Bearing Eclogite in the Western Dabie Mountain,Central China

The high-pressure (HP) eclogite in the western Dabie Mountain encloses numerous hornblendes,mostly barroisite.Opinions on the peak metamorphic P-T condition,PT path and mineral paragenesis of it are still in dispute.Generally,HP eclogite involves garnet,omphacite, hornblendes and quartz,with or without glaucophane,zoisite and phengite.The garnet has compositional zoning with X_(Mg) increase,X_(Ca) and X_(Mn) decrease from core to rim,which indicates a progressive metamorphism.The phase equilibria of the ...     

饱和流沙和苔藓结皮在蒸发过程中的水分特征研究

利用Star-1微型水分蒸发测定系统（SC-DLO,Wageningen, Netherlands）研究了饱和流沙（后文简称流沙）和苔藓结皮（取自1956年人工固沙植被区）蒸发过程中水势、蒸发量和水分特征曲线的变化特点。研究发现,流沙和苔藓结皮的水势在蒸发过程中呈现出各自特点,而且其蒸发的持续时间也具有明显差异;流沙和苔藓结皮的蒸发量都经历了先稳定,后增加,最后又降低三个过程,但流沙的蒸发量比同期纯水稍高,而苔藓结皮与纯水基本无明显差异;在相同吸力条件下,流沙释放的植物可以利用的有效水比苔藓结皮多近1/5,故苔藓结皮的持水能力明显强于流沙。对流沙和苔藓结皮蒸发过程中的水势、蒸发量和不同吸力条件下土壤体积含水率所做的统计分析表明:流沙和苔藓结皮的水势和不同吸力条件下土壤的体积含水率具有显著性差异,而两者的蒸发量没有明显差异。     

大别山西段含蓝闪石-蓝晶石榴辉岩的相平衡研究

目前对于大别山西段超高压榴辉岩仍存在一些不清楚的问题和模糊的认识,如蓝闪石和蓝晶石组合的稳定范围,峰期温压条件和矿物组合,以及早期退变质过程的矿物演化和流体作用.本文对取自大别山西段新县高压-超高压榴辉岩单元内不同地点的超高压榴辉岩样品进行了详细的岩石学和矿物学研究,在此基础上使用相平衡定量分析方法的PT视剖面图对它们进行了正演模拟计算,结果表明含蓝闪石和蓝晶石榴辉岩处于相对低温或低压的蓝闪石榴辉岩和相对高温高压的蓝晶石榴辉岩的过渡区,其稳定的温压范围大致为温度590～700 ℃,压力1.7～3.3 GPa,而且压力大于2.5 GPa时温度范围很窄,为600～640 ℃.由石榴石边缘成分和PT视剖面图确定的榴辉岩峰期温压条件为压力2.85～2.95 GPa和温度625～630 ℃,峰期矿物组合为石榴石+绿辉石+蓝闪石+蓝晶石+硬柱石+柯石英±多硅白云母.峰期之后,榴辉岩经历了快速近等温降压(ITD)的早期高压退变质作用,这是一个非平衡过程,所发生的主要变化如下柯石英→石英,硬柱石→黝帘石+蓝晶石,在相对富镁岩石中出现滑石,当水含量较高时可以出现钠云母,蓝闪石在原来基础上有一定量的生长,并且绿辉石和多硅白云母很可能只部分地发生了成分变化,而石榴石几乎未发生改变.这样形成了目前观察到的矿物组成为石榴石+绿辉石+蓝闪石+蓝晶石+黝帘石/绿帘石+石英±多硅白云母±钠云母±滑石,它代表了UHP榴辉岩在早期高压退变质阶段结束时所具有的矿物组成,这一阶段结束时的温压条件大致为2.0～2.2 GPa和600～630 ℃;早期高压退变质阶段是脱水过程,流体是内部缓冲的.