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111.
鄂尔多斯盆地三叠系延长组7段(长7段)中—低熟(Ro<1.0%)页岩面积占该段页岩总面积的90%左右,中—低熟页岩油/油页岩资源丰富,原位转化作为实现其工业开采的有效途径日益受到各方的关注。生烃转化率和活化能是影响页岩原位转化和开采潜力的关键因素,前人研究表明研究区长7段页岩生烃活化能分布特征存在较大的差别,但其分布规律及其控制因素尚不清楚,尤其是有机质丰度、成熟度等对页岩生烃特征和动力学过程的控制作用及其成因机制尚不明确,这必将制约研究区页岩原位转化条件和资源潜力的评价。本次研究选取了长7段成熟度相近、不同有机质丰度的5块页岩样品以及有机质丰度相近、不同成熟度的5块页岩样品,通过开放热模拟实验确定了样品的生烃动力学参数,讨论了有机质丰度和成熟度对长7段页岩动力学特征的影响。根据烃源岩生烃过程的时间-温度补偿原理,将实验室条件下获得的动力学参数外推至页岩原位转化条件下,分析了有机质丰度和成熟度对长7段页岩原位转化温度区间的影响。结果表明,在成熟度相近的情况下,受有机质中藻类体等腐泥组的富集程度影响,烃源岩的生烃活化能随有机质丰度的增大而增大;在有机质丰度相近...  相似文献   
112.
根据已有地理信息地形数据,经过地形数据分析和计算,采用六边形连接方式扩张到整个区域的算法,通过坡度信息和行走速率,建立三维地理信息行走扩张域模型,然后对模型进行了优化研究,并在智慧城市及路径规划等方面进行了应用研究.  相似文献   
113.
研究利用高分辨率遥感影像,结合基础地理信息数据、规划数据、外业调查及其他参考资料,开展了全市建制镇建设用地人机交互式遥感解译,对建制镇建设现状及空间格局特征,建制镇与地形地貌、河流水系相关性,以及建制镇空间形态等进行了定量化分析研究.结果表明:全市建制镇现状建设大部分在0.5 km2以下,重点镇平均规模明显高于其他建制镇;空间上建制镇呈现西部、中部偏北等区域分布较为密集且建设规模较大,东南部和东北部区域较为稀疏且规模较小等特征;建制镇主要建设在丘陵和山地地貌上,建设数量占比超过65%,平原、台地上也有部分建设,河谷区域布局较少,且在高程200—400 m区间建设的建制镇超过一半;空间形态上,以组团型布局为主,具有集中型、带型、放射型等多样特征,建制镇的研究对于未来优化建制镇布局、统筹城乡一体化发展具有重要指导作用.  相似文献   
114.
惠民超大型铁矿床处在西南三江复合造山带中南段的昌宁-孟连结合带东侧,具有火山-沉积岩容矿、磁铁矿-菱铁矿矿化组合及普遍伴生热液蚀变的突出特点。目前,因其赋矿地层时代存在分歧,致使其矿床成因认识不清。野外地质调查表明,矿区内原划分为澜沧岩群惠民岩组的岩石组合可分为两个构造地层单元,即:下部为中—晚奥陶世弧火山岩组合,受到古特提斯洋俯冲增生作用的改造,显示一定的构造混杂特点,局部见铁铜矿化;其上被一套火山-沉积岩组合不整合覆盖。上覆火山-沉积岩由玄武岩、安山岩、凝灰岩及硅质岩组成,属于弧前环境沉积组合,是已知铁矿体的主要赋矿层位,至少可分为3个完整的火山沉积旋回,其间多为整合接触。铁矿体呈层状、似层状多层次产于火山岩、硅质岩中,显示同生沉积成矿特点,普遍伴生陡倾斜(细)脉状铁矿化。容矿火山岩上部火山岩及火山碎屑岩中岩浆锆石U-Pb测年结果显示,其结晶年龄位于235~214 Ma之间,峰期年龄为230~225 Ma,指示铁矿床成矿时代属晚三叠世。由此提出,惠民超大型铁矿床是一个早中生代火山沉积型矿床,其成矿严格受到晚三叠世(可早至晚二叠世)古特提斯洋向东俯冲消减(现今地理方位)有关弧火山活动...  相似文献   
115.
西沙西科1井第四系生物礁-碳酸盐岩的岩石学特征   总被引:1,自引:0,他引:1       下载免费PDF全文
孙志鹏  尤丽  李晓  刘立  廖静  刘娜  赵爽  于亚苹 《地球科学》2015,40(4):653-659
从西科1井生物礁-碳酸盐岩的岩心观察和岩石学特征的分析入手, 重点刻画了第四系全新-更新统乐东组生物礁-碳酸盐岩的岩石类型和生物礁类型.543片铸体薄片分析和214.89 m岩心观察表明: 岩石类型主要为粒泥灰岩、泥粒灰岩和骨架灰岩, 其次为粘结灰岩、颗粒灰岩、漂砾灰岩和砾屑灰岩.在纵向上, 埋深0~10 m层段以颗粒灰岩为主, 埋深10~22 m层段为生物碎屑砂分布段, 埋深22.00~214.89 m层段以粒泥灰岩、泥粒灰岩和骨架灰岩为主.生物礁类型以骨架礁为主, 造礁生物为珊瑚和少量珊瑚藻.骨架礁在埋深0~214.89 m均有发育, 丛状和块(段)状礁仅分布于埋深83~98 m.   相似文献   
116.
A variety of Earth observation systems monitor the Earth and provide petabytes of geospatial data to decision-makers and scientists on a daily basis. However, few studies utilize spatiotemporal patterns to optimize the management of the Big Data. This article reports a new indexing mechanism with spatiotemporal patterns integrated to support Big Earth Observation (EO) metadata indexing for global user access. Specifically, the predefined multiple indices mechanism (PMIM) categorizes heterogeneous user queries based on spatiotemporal patterns, and multiple indices are predefined for various user categories. A new indexing structure, the Access Possibility R-tree (APR-tree), is proposed to build an R-tree-based index using spatiotemporal query patterns. The proposed indexing mechanism was compared with the classic R*-tree index in a number of scenarios. The experimental result shows that the proposed indexing mechanism generally outperforms a regular R*-tree and supports better operation of Global Earth Observation System of Systems (GEOSS) Clearinghouse.  相似文献   
117.
基于菱形单元的球面离散格网具有结构简单和方向性一致等优点,使得其适用于全球多尺度空间数据建模与分析.本文提出一种球面菱形离散格网正二十面体剖分法.首先根据地球的主要地理特征确定正二十面体各个顶点在球面上的位置;其次针对南北两极处的极点奇异性,建立了球面经纬度坐标与三维直角坐标之间的转换关系,在此基础上提出球面菱形离散格网层次递归剖分算法,并从菱形格网单元面积、长短轴比两方面对剖分结果进行几何形变分析;最后验证了本文方法的可行性,试验结果表明,该方法可有效地构建基于正二十面体的球面菱形离散格网,其总体几何特性明显优于基于正八面体构建的球面菱形离散格网.  相似文献   
118.
针对气象信息网络常规运行监控业务需要,结合气象信息共享系统(China Integrated Meteorological Information Service System,简称CIMISS)的运维实际,设计开发了基于CIMISS的气象数据处理时效监视系统,实现了对13类上行气象观测数据处理主要的节点时效、自动站疑误数据处理、数据访问服务性能的实时监控,并可为部分气象观测设备的运维保障提供参考指引。文中从系统结构与数据流程、主要业务功能、技术实现等方面对系统的实现方式等进行了介绍。  相似文献   
119.
The status of fishery stocks in the coastal waters of China is far from ideal, mainly due to climate change and the impacts of human activities (e.g., pollution and overfishing). Thus, the restoration and protection of fishery resources have become critical and complex. The stability and balanced structure of the fish community is a basic foundation for the protection of fishery resources. Based on data collected from bottom trawls by the R/V Beidou in continental shelf of the East China Sea in November 2006 and February 2007, changes in the composition and diversity of fish species and functional groups were analyzed. The research area was divided into offshore waters and inshore waters by the two-way indicator species analysis (TWIA). The results showed that the dominant species were different between offshore waters and inshore waters and also varied with the survey time. The most abundant family was Sciaenidae and Teraponidae in November 2006, Sciaenidae, Engraulidae and Triglidae were most abundant in February 2007. The species belonged mainly to mobile piscivores (G6), benthivores/piscivores (G4), benthivores (G3) and planktivores (G1), and the dominant species in November 2006 were commercial species (e.g. Larimichthys polyactis and Trichiurus japonicus), but small-sized species were dominant in February 2007 (e.g., Harpadon nehereus, Benthosema pterotum, Champsodon capensis, and Acropoma japonicum). The species diversity showed a similar trend as the functional group diversity. Stations with higher diversity were mainly distributed in inshore waters in February 2007, whereas higher diversity was found in offshore waters in November 2006. The highest biomass and species number were found in G6 group, followed by the G4, G5 and G1 groups. The distribution of the number of individuals of each functional group showed the opposite trend as that of the biomass distribution. In addition, the size spectra were mainly concentrated around 3–29 cm, and the individual number of fish species gradually decreased with the increase in body size, but the relative biomass showed a moderate fluctuation in each size class. These changes showed that species with faster growth rate and earlier maturity age became dominant in continental shelf of the East China Sea. So the variations in biological characteristics of fish should be fully considered in maintaining sustainable utilization of fishery resource.  相似文献   
120.
The datasets of two Ocean Model Intercomparison Project(OMIP)simulation experiments from the LASG/IAP Climate Ocean Model,version 3(LICOM3),forced by two different sets of atmospheric surface data,are described in this paper.The experiment forced by CORE-II(Co-ordinated Ocean–Ice Reference Experiments,Phase II)data(1948–2009)is called OMIP1,and that forced by JRA55-do(surface dataset for driving ocean–sea-ice models based on Japanese 55-year atmospheric reanalysis)data(1958–2018)is called OMIP2.First,the improvement of LICOM from CMIP5 to CMIP6 and the configurations of the two experiments are described.Second,the basic performances of the two experiments are validated using the climatological-mean and interannual time scales from observation.We find that the mean states,interannual variabilities,and long-term linear trends can be reproduced well by the two experiments.The differences between the two datasets are also discussed.Finally,the usage of these data is described.These datasets are helpful toward understanding the origin system bias of the fully coupled model.  相似文献   
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