Characteristics of Pre-summer Daytime Cloud Regimes over Coastal South China from the Himawari-8 Satellite

Using the high spatiotemporal resolution (2 km-and-10 min) data from the Advanced Himawari Imager onboard the Himawari-8 satellite, this study documents the fine-scale characteristics of daytime cloud regimes (CRs) over coastal South China during the pre-summer rainy season (April–June). Six CRs (CR1–CR6) are identified based on the joint frequency distribution of cloud top brightness temperature and cloud optical thickness, namely, the optically thin-to-moderate cloud mixture, optically thin warm clouds with cirrus, optically thick warm clouds, weak convective cloud mixture, strong convective clouds, and extreme, deep convective clouds. The optically thick warm clouds are the major CR during April and May, with higher frequencies over land, especially along the urban agglomeration, rather than the offshore which may be an indicator of the higher aerosol concentrations being a contributing factor over the cities. The CRs with weak convective cloud mixtures and strong convective clouds appear more frequently over the land, while the two CRs with optically thinner clouds occur mainly offshore. Synoptic flow patterns (SPs) are objectively identified and examined focusing on those favoring the two major rain-producing CRs (CR5 and CR6) and the highly reflective CR with optically thick warm clouds (CR3). The two SPs favoring CR5 and CR6 are characterized by abundant moisture with low-level jets after monsoon onset, and a northwest high-southeast low pattern with strong dynamic convergence along the coastline, respectively. The non-convective CR3 with high reflectance is related to a SP that features the western North Pacific subtropical high extending more westward, leading to a moderate moisture supply and a wide range of convective available potential energy, but also, large convective inhibition.     

Tectonically‐controlled Evolution of the Late Cenozoic Nihewan Basin,North China Craton: Constraints from Stratigraphy,Mineralogy, and Geochemistry

The Late Cenozoic basins in the Weihe–Shanxi Graben, North China Craton are delineated by northeast-striking faults. The faults have, since a long time, been related to the progressive uplift and northeastward expansion of the Tibetan Plateau. To show the relation between the basins and faults, two Pliocene–Pleistocene stratigraphic sections(Chengqiang and Hongyanangou) in the southern part of the Nihewan Basin at the northernmost parts of the graben are studied herein. Based on the sedimentary sequences and facies, the sections are divided into three evolutionary stages, such as alluvial fan-eolian red clay, fan delta, and fluvial, with boundaries at ~2.8 and ~1.8 Ma. Paleocurrent indicators, the composition of coarse clastics, heavy minerals, and the geochemistry of moderate–fine clastics are used to establish the temporal and spatial variations in the source areas. Based on features from the middlenorthern basin, we infer that the Nihewan Basin comprises an old NE–SW elongate geotectogene and a young NW–SE elongate subgeotectogene. The main geotectogene in the mid-north is a half-graben bounded by northeast-striking and northwest-dipping normal faults(e.g., Liulengshan Fault). This group of faults was mainly affected by the Pliocene(before ~2.8–2.6 Ma) NW–SE extension and controlled the deposition of sediments. In contrast, the subgeotectogene in the south was affected by northwest-striking normal faults(e.g., Huliuhe Fault) that were controlled by the subsequent weak NE–SW extension in the Pleistocene. The remarkable change in the sedimentary facies and provenance since ~1.8 Ma is possibly a signal of either weak or strong NE–SW extension. This result implies that the main tectonic transition ages of ~2.8–2.6 Ma and ~1.8 Ma in the Weihe–Shanxi Graben are affected by the Tibetan Plateau in Pliocene–Pleistocene.     

藏南松多地区板多铅锌矿床流体包裹体特征及矿床成因

藏南松多地区板多铅锌矿床位于冈底斯成矿带东段,矿床产于松多岩组、花岗闪长岩与隐伏似斑状花岗岩的接触带及其附近,迄今共圈定3个矿体,矿体呈脉状、透镜状,受北东向断裂控制。矿石中主要金属矿物为方铅矿、闪锌矿与黄铜矿,其次为毒砂、黄铁矿、磁黄铁矿等;非金属矿物以石英、绢云母为主,其次为白云母与方解石。矿床可划分为3个成矿阶段:Ⅰ.石英-毒砂-黄铁矿-磁黄铁矿阶段;Ⅱ.石英-黄铁矿-闪锌矿-黄铜矿-方铅矿阶段;Ⅲ.石英-方解石阶段。其中,第Ⅱ阶段为主成矿阶段。为查明成矿物理化学条件和成矿流体特征,选取主要成矿阶段的石英开展流体包裹体岩相学和显微测温研究。结果表明,石英主要发育气液两相包裹体,并含有少量纯液相与纯气相包裹体;成矿流体属中温、低盐度、低密度的Na Cl-H2O体系;成矿早期存在沸腾现象,之后,流体的减压降温应是铅锌富集成矿的主要因素。综合成矿地质条件、矿床地质特征及流体包裹体研究,初步认为,板多铅锌矿属中温热液脉型铅锌矿床。     

长庆油田小套管二次固井工艺技术研究与应用

针对长庆油田?139.7 mm生产套管中下?88.9 mm小套管二次固井环空间隙小、固井施工压力高,水泥环薄、密封完整性难以满足后期措施需求,固井前井筒界面环境差、二界面水泥胶结不佳等技术难点,通过技术创新及改进,研制出适用于小套管二次固井的低摩阻耐压防漏水泥浆体系、热固性树脂水泥浆体系,结合自主研发的界面增强型冲洗液和固井压塞液体系,形成一套长庆油田小套管固井工作液体系。优选性能可靠的固井配套工具,优化小套管固井管串结构,按照平衡压力固井原理,采用一次上返固井工艺,总结出了一套小套管二次固井工艺技术。现场应用10口井,固井质量优良率95%,增产效果显著,为长庆油田老井增潜挖效及套损井治理提供了有力的技术支撑。     

Geochemical insights into contribution of petroleum hydrocarbons to the formation of hydrates in the Taixinan Basin,the South China Sea

Methane hydrate in the South China Sea(SCS)has extensively been considered to be biogenic on the basis of itsδ13C and δD values.Although previous efforts have greatly been made,the contribution of thermogenic oil/gas has still been underestimated.In this study,biomarkers and porewater geochemical parameters in hydrate-free and hydrate-bearing sediments in the Taixinan Basin,the SCS have been measured for evaluating the contribu-tion of petroleum hydrocarbons to the formation of hydrate deposits via a comparative study of their source inputs of organic matters,environmental conditions,and microbial activities.The results reveal the occurrence of C14-C16 branched saturated fatty acids(bSFAs)with relatively high concentrations from sulfate-reducing bacteria(SRBs)in hydrate-bearing sediments in comparison with hydrate-free sediments,which is in accord with the positive δ13C values of dissolved inorganic carbon(DIC),increasing methane concentrations,decreasing alka-linity,and concentration fluctuation of ions(Cl-,Br,SO2-,Ca2+,and Mg2+).These data indicate the relatively active microbial activities in hydrate-bearing sediments and coincident variations of environmental conditions.Carbon isotope compositions of bSFAs(-34.0％o to-21.2％o),n-alkanes(-34.5％o to-29.3％o),and methane(-70.7％o to-69.9％o)jointly demonstrate that SRBs might thrive on a different type of organic carbon rather than methane.Combining with numerous gas/oil reservoirs and hydrocarbon migration channels in the SCS,the occurrence of unresolved complex mixtures(UCMs),odd-even predominance(OEP)values(about 1.0),and biomarker patterns suggest that petroleum hydrocarbons from deep oil/gas reservoirs are the most probable carbon source.Our new results provide significant evidence that the deep oil/gas reservoirs may make a contribution to the formation of methane hydrate deposits in the SCS.     

基于MAPGIS二次开发的采矿权登记信息自动矢量化

以MAPGIS6.7为平台,结合VB6.0和ACEESS数据库进行二次开发,实现了采矿权登记信息数据库精确、快速的自动矢量化,为矿山遥感调查与监测项目提供了强有力的技术支持,有效提高了实际工作效率。     

电感耦合等离子体质谱法(ICP-MS)测定紫菜、螺旋藻中的硒

应用电感耦合等离子体质谱法测定了紫菜、螺旋藻中硒。采用微波消解,直接测定。其方法检出限低,准确度好。     

青藏高原典型盐湖硼矿床成矿条件对比与矿床模式研究

选取青藏高原扎仓茶卡和大柴旦典型盐湖硼酸盐矿床,分别从区域地质背景、气候条件、区域水文地球化学、同位素地球化学以及硼地球化学特征等方面开展研究。结果表明,扎仓茶卡和大柴旦盐湖固体硼酸盐矿床的形成受控于硼自身内在地球化学特性以及外在控制条件,特别是构造运动、第四纪以来的干旱气候条件以及丰富的物源等控制因素,青藏高原盐湖硼酸盐矿床的形成是内外条件耦合的结果。基于扎仓茶卡和大柴旦盐湖硼酸盐矿床的成矿条件和成矿模式的研究,确立青藏高原高寒干旱盐湖区盐湖硼酸盐矿床成矿模式为高山—深盆—浅水成矿模式。     

迭代EnSRF方案设计及在Lorenz96模式下的检验

本文利用非同步 (Asynchronous) 算法设计了一个包含迭代过程的集合平方根滤波方案 (迭代EnSRF),并在Lorenz96模式下详细对比分析了该方案和传统EnSRF方案的同化效果.与传统EnSRF方案不同,迭代EnSRF方案能够同时更新两个时次的背景场并通过迭代过程来改进分析结果.本文不仅检验了迭代EnSRF在同化不同类型观测资料时的效果,还检验了存在模式误差时该方案的同化效果,并且对同化结果的合理性进行了详细分析.试验结果表明:在完美模式下,迭代EnSRF能够显著加快同化常规观测时的收敛速度,并能够更加有效地同化非常规观测资料;在存在模式误差时,迭代EnSRF并不能有效改进分析结果;当对不准确的模式参数进行扰动后,迭代EnSRF能够更好地利用改进后的集合预报系统来提高其对部分类型观测的分析结果.进一步的分析表明,分析结果的改进主要得益于迭代EnSRF改进了背景误差协方差空间结构,并使得EnSRF的线性假设得到更好的满足.     

基于GIS的天津市滨海新区地下管线管理系统设计与实现

以天津市滨海新区为例,给出了城市地下管线管理系统的设计框架,分析了管线系统与一般GIS的差别,实现了管线信息的动态更新与维护、空间及属性分析与统计、各种数据输出等功能.