遥感与地理信息系统在三峡库区城镇迁建选址中的应用研究

根据山地城镇建设的发展现状,运用遥感和地理信息系统技术工具,在获取、分析三峡库区综合环境指标的基础上,以巫山县为例,建立了巫山县空间环境数据库,并提出了巫山县县城修建性选址模型。此模型的建立可以为其他三峡库区城市迁建综合环境研究提供合理的方案和措施。       

南极布兰斯菲尔德海峡表层沉积物烷基芳烃化合物

芳烃化合物广泛分布于沉积物(古老和现代)、石油和煤炭中,它与沉积有机质的演化与成熟度有着密切的关系,如二甲基素的相对丰度变化,反映了有关沉积物成熟度的信息;又如二甲基带与三甲基察的相对丰度可作为原油成熟度的标志,它优于以生物标志物作为依据的指标[1].     

利用 ASP 技术搭建台站地震设备管理平台

借助网络,利用 ASP 技术,整合近几年台站地震设备采购及维修情况,提出基于 Web 方式的录入、查询、修改管理平台。     

福建明溪锆石的改色研究

福建明溪的锆石以灰褐色为多，通过热处理可将其改成浅蓝色或无色。本文讨论了热处理的温度、时间、氧化还原条件以及样品的性质对热处理结果的影响，认为热处理的温度过高过低，时间过长都不利于锆石颜色的改善，交替改变氧化还原条件，锆石颜色的改变可逆。在相同的热处理条件下，不同样品的改色效果不同。在此研究基础上提出了锆石的“二步法”改色工艺，并对改色结果的稳定性和热处理对锆石性质的影响进行了评估。     

滇东北Pb-Zn-(Ag)多金属矿床找矿突破关键基础地质问题

梳理过去几十年对滇东北地区铅锌（银）多金属矿的科学研究成果和找矿勘查经验发现,一些影响找矿突破的关键基础地质问题始终难以达成共识或长久未被解决。文章以“三位一体”找矿预测方法为指导,围绕成矿地质体、成矿构造及成矿作用特征标志等直接影响推测矿体（床）全部地质特征的内容进行系统论述,综合分析认为：滇东北地区主要产出以茂租铅锌矿为代表的层控型矿床和以乐红铅锌矿为代表的构造控矿型矿床,成矿地质体为高原陆核地体系统内的坳陷盆地,成矿构造主要为SN向深断裂带、NW向深断裂带及NE向深断裂所引起的次生构造,矿床成因与沉积及后期热液改造有直接关系,成矿时代主要集中在晚三叠世,成矿物质主要来源于震旦系碳酸盐岩地层,成矿机制为古特提斯向扬子板块西南缘俯冲驱动陆内盆地的热、气、液反复循环,不断改造-萃取-富集成矿。     

吉林省白头山火山岩的岩石学研究

白头山火山位于吉林省东部,主要由一套粗面岩—钠闪碱流岩组成。岩石中长石斑晶的成分表现出逐步富Or的趋势。单斜辉石早期向富Fe,而晚期表现为向富NaFe³⁺Si₂O₆的方向演化。矿物成分变化规律的研究揭示了白头山火山岩与长白山玄武岩之间的成因联系。岩石主要元素化学成分在过碱性酸性岩系统的Q—Ab—Or相图及SiO₂—Al₂O₂—Na₂O+K₂O图上的投影,表明了白头山火山岩的演化主要是受碱性长石的分离结晶所控制,但在从粗面岩到石英粗面岩的演化过程中涉及少量斜长石组分的分离结晶。用最小二乘法对白头山火山岩的成因及其演化过程进行了定量模拟。所得结果与岩相学和岩石化学的分析结果相吻合,证实了白头山火山岩是由长白山玄武岩分离结晶形成的成因假说。根据热力学计算和过碱性岩石的高温高压实验,推测岩浆形成温度分别为1074—928℃,形成压力约在2-3kb。     

The origin of spongy texture in minerals of mantle xenoliths from the Western Qinling, central China

Spongy textures are observed in mantle peridotite xenoliths hosted in Cenozoic kamafugites from the Western Qinling, central China. These textures are mainly developed in clinopyroxenes and spinels, and occur as spongy rims consisting of low-Na clinopyroxene, ilmenite, and bubbles, enclosing nonspongy cores. The ilmenites and bubbles exhibit shapes and sizes that vary with the width of the spongy rims. The spongy-textured minerals preserve primary shapes and well-defined grain boundaries and do not show apparent interaction with contact minerals or observed melts except the subsequent melts forming melt pockets. The xenocrysts display reactive zoning textures with host magmas rather than spongy textures. Compositionally, the spongy rims are enriched in Ca, Ti, and most trace elements, have high Cr#, and are depleted in Na, Al, Fe, Al^VI, and Al^IV/Al^VI compared with the cores. These observations suggest that melts/host magmas did not play any significant role in the formation of the spongy textures. We therefore propose that spongy-textured clinopyroxenes and spinels in Western Qinling peridotite xenoliths developed from a decompression-induced partial melting event prior to formation of melt pockets and xenolith entrainment in host magmas.     

地面伽马能谱测量在我国地质填图中的初步应用

近年来,由于核技术的发展和认识的转变,地面γ能谱测量等放射性方法在我国地质填图工作中已得到广泛应用。本文介绍地面伽马能谱测量等放射性方法在我国地质填图中的作用及应用情况。     

重庆市区冬季热岛和湿岛效应的研究

1989年12月15日——1990年1月15日,重庆雾害课题组在市区进行了包含地面气象、边界层气象和大气污染等多种项目的外场综合观测。本文利用此观测资料,分析了城市热岛的水平分布,热岛和湿岛的垂直结构及其成因。     

中国东北耕地物候期对气候变化的响应(英文)

We investigated the responses of cropland phenophases to changes of agricultural thermal conditions in Northeast China using the SPOT-VGT Normalized Difference Vegetation Index (NDVI) ten-day-composed time-series data, observed crop phenophases and the climate data collected from 1990 to 2010. First, the phenological parameters, such as the dates of onset-of-growth, peak-of-growth and end-of-growth as well as the length of the growing season, were extracted from the smoothed NVDI time-series dataset and showed an obvious correlation with the observed crop phenophases, including the stages of seedling, heading, maturity and the length of the growth period. Secondly, the spatio-temporal trends of the major thermal conditions (the first date of ≥10℃, the first frost date, the length of the temperature-allowing growth period and the accumulated temperature (AT) of ≥10℃) in Northeast China were illustrated and analyzed over the past 20 years. Thirdly, we focused on the responses of cropland phenophases to the thermal conditions changes. The results showed that the onset-of-growth date had an obvious positive correlation with the first date of ≥10℃ (P < 0.01), especially in the northern part of the Songnen Plain, the eastern part of the Sanjiang Plain and the middle and eastern parts of Jilin Province. For the extracted length of growing season and the observed growth period, notable correlations were found in almost same regions (P < 0.05). However, there was no obvious correlation between the end-of-growth date and the first frost date in the study area. Opposite correlations were observed between the length of the growing season and the AT of ≥10℃. In the northern part of the Songnen Plain, the eastern part of the Sanjiang Plain and the middle part of Jilin and Liaoning Provinces, the positive correlation coefficients were higher than the critical value of 0.05, whereas the negative correlation coefficients reached a level of 0.55 (P < 0.05) in the middle and southern parts of Heilongjiang Province and some parts of the Sanjiang Plain. This finding indicated that the crop growth periods were shortened because of the elevated temperature; in contrast, the extended growth period usually meant a crop transformation from early- or middle-maturing varieties into middle or late ones.