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塔里木地区奥陶纪岩相古地理 总被引：11，自引：5，他引：6
本文是《塔里木地区寒武纪岩相古地理》一文的延续。塔里木地区是以当今的塔里木盆地为主体并包括其周边山地的广大地区,北至中天山,南至西昆仑山,西至我国国界,东至阿尔金山,面积逾100万km2 。在98个露头剖面和钻井剖面的各种单因素定量及定性资料的基础上,采用单因素分析多因素综合作图法,编制出了塔里木地区奥陶系下奥陶统两河口阶和红花园阶、中奥陶统大湾阶和牯牛潭阶、上奥陶统庙坡阶、上奥陶统宝塔阶、上奥陶统临湘阶和五峰阶5个作图单位的各种单因素图,并在此基础上编制出了相应的5个地质时期的岩相古地理图。这些岩相古地理图的最主要特征是定量,即每个古地理单元的划分和确定都有确切的定量资料及定量单因素图为依据。这种定量的岩相古地理图在塔里木地区还是首次出现。在早奥陶世两河口期和红花园期,塔里木地区主要是碳酸盐台地,其中散布着各种滩。其北部为南天山盆地,东部为塔东盆地,南部为西昆仑台地,其东侧为东昆仑台地和柴达木台地。无陆地和云坪,盆地面积相当大。这与该地区寒武纪的岩相古地理格局大不相同。这表明早奥陶世的海进比寒武纪的更甚了。中奥陶世大湾期和牯牛潭期的岩相古地理面貌与两河口期和红花园期的相似,但南天山盆地西部扩大了,从而形成了柯坪盆地。这是一个重要变化。庙坡期的古地理面貌与大湾期和牯牛潭期的相似,但滩少了,这标志着海进又发展了且可能到达了盛期。至宝塔期,在塔里木台地的东南部,碎屑岩发育,这是塔里木碳酸盐台地向碎屑岩台地变化的预兆,是海退的标志。到晚奥陶世的临湘期和五峰期,塔里木台地基本上变成了1个碎屑岩台地。这是一个重大变化。这标志着塔里木地区寒武纪和奥陶纪海进海退旋回的终结。 相似文献
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根据水量平衡理论,计算出研究区可利用水资源总量为91.04×10~8m~3。对用水量、水资源利用效率及影响因素进行研究。结果表明:成都市2000~2014年水资源利用效率整体呈Ⅴ型分布,2009年水资源利用效率达到最低值。城镇化的发展对水资源利用效率具有明显的负相关性,而工业水平及经济水平的发展能明显提高水资源利用效率。通过对用水结构的分析发现,城镇化的发展对农业用水影响不大,主要由于成都市水资源充沛,城市和工业的发展对农业用水的挤占不明显。采用BP神经网络模型预测2020年成都市需水量为40.02×10~8m~3,研究区水资源总量满足要求。 相似文献
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Feng Zengzhao Bao Zhidong Wu Maobing Jin Zhenkui Shi Xiaozhang 《Frontiers of Earth Science》2007,1(3):265-274
The Tarim area in this paper refers to the present Tarim Basin and its surrounding mountains, bounded on the north by the
Middle Tianshan Mountains, on the south by the Kunlun Mountains, on the west by the national boundary of China, and on the
east by the Altun Mountains. It covers an area of more than 1 000 000 km2. Based on the quantitative and qualitative data from the stratigraphy and petrology of outcrop and well sections, and according
to the single factor analysis and multifactor comprehensive mapping method, the single factor maps of the Lower, Middle and
Upper Cambrian, and the lithofacies palaeogeography maps of the Early, Middle and Late Cambrian of the Tarim area, are compiled.
The most important character of these lithofacies palaeogeography maps is quantification, i.e. the determination of each palaeogeography
unit based on accurate quantitative data and the quantitative single factor maps. The study marks the first time that this
quantitative method has been applied in the Tarim area. In the Early Cambrian, the present Tarim Basin was mainly a carbonate
platform, in which there were penebank, dolostone flats, and gypsum-halite lake. The South Tianshan Basin and East Tarim Basin
were siliceous rock-limestone-mudstone basins. The Kunlun Platform was situated in the south, where there were two small lands.
The Altun Land was situated in the southeast. In the Middle and Late Cambrian, the framework of lithofacies palaeogeography
was similar to that in the Early Cambrian; the land area was gradually reduced; the basin area was enlarged; while the Tarim
Carbonate Platform changed little. The transgression continued from the Early Cambrian to the Late Cambrian.
Translated from Journal of Palaeogeography, 2006, 8(4): 427–439 [译自: 古地理学报] 相似文献
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1 INTRODUCTION Soil erosion is serious in Western China. With the implementation of a development strategy for western China, soil and water conservation and ecological restoration in western China earn more attention because economic development requires parallel efforts on ecological restoration. To protect the ecology of the upper reaches of the Yangtze River, integrated management of sediment and ecological restoration are being conducted in Sichuan Province. The Yufeng Watershed… 相似文献
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