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31.
The hydrothermal ore-forming paleosystem of the Mnogovershinnoe deposit is reconstructed by defining lithothectonic elements constituting ore-bearing zones with account for their formation mechanisms and positions in the conditional geochronological scale of the hydrothermal activity and isotopic data. The use of lithotectonic elements for deciphering ore genesis events made it possible to take into account both synchronously and successively formed parts of ore bodies, which substantially improved the quality of the reference data for developing a dynamic model of the deposit. The approach proposed for reconstructing the hydrothermal paleosystem of the Mnogovershinnoe deposit may be used for developing models of other ore objects. 相似文献
32.
文章采用沉积学、岩石学、地球化学原理,对柴达木盆地石炭系葡萄状缝洞分布特征与成因机理进行了研究,并与四川盆地灯影组缝洞进行了对比分析。研究结果表明：柴达木盆地石炭系东部石炭系葡萄状缝洞与四川盆地灯影组葡萄状缝洞具相似的岩石学特征,可见复式纹层花边皮壳,网状泄水通道,以及大气淡水方解石、陆源砂屑、泥以及硅质自生矿物等缝洞内包卷物等岩石学标志。地化分析显示缝洞皮壳碳酸盐矿物成岩流体为海水,缝洞碳酸盐充填物的成岩流体为大气淡水。最终认为两地葡萄状缝洞皆为大气水作用的产物,柴东石炭系葡萄状灰岩缝洞是四川盆地灯影组葡萄状白云岩缝洞早期形式。二者演化过程如下：由于周期性海退使潮坪相等环境下形成的碳酸盐岩暴露而遭受溶蚀,海侵时溶蚀缝洞内形成针柱状方解石胶结,当海水进一步蒸发,胶结的针柱状方解石在海水中发生模仿交代,形成同生期白云石,这种周期性的海退海侵形成在剖面上的多套葡萄状缝洞旋回。 相似文献
33.
总结了金川公司园林公司6年来在戈壁地区建设葡萄园形成的一整套技术。阐述了在戈壁地区栽培葡萄,进行带状客土栽培,采用连体大棚架独龙干超短枝整形修剪,合理施用有机肥和化肥,连通固定防寒沟及土加覆盖物防寒,苗期搭小拱架加速生长等关键措施。分析了本套技术适应特点及在改造戈壁生态中的优势,认为本套技术适用于葡萄需埋土防寒地区开发荒漠,对推广应用应注意的问题提出了建议。 相似文献
34.
The Early Cretaceous coal‐forming plants of southern part of East Siberia and Russian Far East 
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下载免费PDF全文 For the first time the plants that gave rise to the Early Cretaceous coals of Transbaikalia (Khilok, Chita‐Ingoda, Bukachacha, and Turga‐Kharanor basins), Amur River region (Bureya Basin), and Primorye region (Razdolnaya River and Partizansk River basins) have been obtained. The plants that produced coals mainly belong to the ginkgoaleans (Pseudotorellia, Sphenobaiera, and Baierella), bennettites, and conifers having pinaceous, taxodiaceous, araucariaceous affinity, as well as extinct cheirolepidiaceous and miroviaceous plants. A parallel palynological study has identified a number of the same elements in addition to the cyatheaceous, gleicheniaceous, osmundaceous, and schizaeaceous ferns. 相似文献
35.
Floodplain wetlands in the China side of the Amur River Basin (CARB) undergone consistent decreases because of both natural and anthropogenic drivers. Monitoring floodplain wetlands dynamics and conversions over long-time periods is thus fundamental to sustainable management and protection. Due to complexity and heterogeneity of floodplain environments, however, it is difficult to map wetlands accurately over a large area as the CARB. To address this issue, we developed a novel and robust classification approach integrating image compositing algorithm, objected-based image analysis, and hierarchical random forest classification, named COHRF, to delineate floodplain wetlands and surrounding land covers. Based on the COHRF classification approach, 4622 Landsat images were applied to produce a 30-m resolution dataset characterizing dynamics and conversions of floodplain wetlands in the CARB during 1990–2018. Results show that (1) all floodplain land cover maps in 1990, 2000, 2010, and 2018 had high mapping accuracies (ranging from 90 %±0.001–97%±0.005), suggesting that COHRF is a robust classification approach; (2) CARB experienced an approximately 25 % net loss of floodplain wetlands with an area declined from 8867 km2 to 6630 km2 during 1990–2018; (3) the lost floodplain wetlands were mostly converted into croplands, while, there were 111 km2 and 256 km2 of wetlands rehabilitated from croplands during periods of 2000–2010 and 2010–2018, respectively. To our knowledge, this study is the first attempt that focus on delineating floodplain wetlands at a large-scale and produce the first 30-m spatial resolution dataset demonstrating long-term dynamics of floodplain wetlands in the CARB. The COHRF classification approach could be used to classify other ecosystems readily and robustly. The resultant dataset will contribute to sustainable use and conservation of wetlands in the Amur River Basin and provide essential information for related researches. 相似文献
36.
以吐鲁番主要农区为试验区，运用多源遥感数据融合图像进行土地利用现状调查及葡萄种植面积遥感调查。运用IHS变换方法进行了研究区多光谱与全色高分辨率图像的融合工作，生成了质量较好的图像。用于土地分类及葡萄面积提取。在对研究区土地利用类型的分类中，本文采用的分类方法是结合目视判读的经验，在无监分类法和有监分类法的基础上，辅以地面数据，在遥感图像处理常规分类方法的范畴内，采取最大程度的有利于提高分类精度的措施，得到了全试验区相对最高的计算机自动分类精度65％；然后采取分区分类或人工解译改进分类结果，可使研究区的土地利用分类精度超过90％。因此，此方法在土地利用现状调查及作物面积监测中是可行的。 相似文献
37.
Jurassic and Early Cretaceous Radiolaria of the Lower Amurian Terrane: Khabarovsk region, far east of Russia 总被引：3，自引：0，他引：3
New data on biostratigraphy, sedimentology and tectonics of the Russian Far Eastern region (Lower Amurian terrane) are presented. This study shows that sedimentary sequence of the terrane consists of interbedded Radiolaria-bearing siliceous and volcaniclastic sediments spanning an interval of over 90 million years. It is shown that accumulation of radiolarian deposits on an oceanic plate was associated with alkaline (intraplate) volcanism in the Jurassic, while the plate was drifting, and with some arc volcanism during the Early Cretaceous. The younger siliceous rocks contain volcaniclastic material and indicate that the studied sequence approached the trench in the Early Cretaceous (Hauterivian-Barremian) and became accreted in the late Albian–early Cenomanian. We describe and illustrate radiolarian species extracted from 21 samples. A taxonomic list of 194 taxa and nine plates of Jurassic–Early Cretaceous Radiolaria are presented. 相似文献
38.
V. I. Sinyukov V. A. Glukhov O. V. Rybas A. N. Makhinov V. I. Kim N. V. Berdnikov 《Russian Journal of Pacific Geology》2008,2(6):545-552
The dynamics of river channel processes were analyzed in the region of complex floodplain-channel branching of the Amur River near Khabarovsk using remote sensing data of the Earth’s surface. Zones of steady accumulation and long-term erosion of the river channel are established within the Khabarovsk water junction over the period of 1964–2004. The main problems related to restoring the Amur River back to its initial channel were distinguished in the course of these works. A map of individual streams formed in the Amur River channel under the influence of large tributaries (the Sungari and Ussuri rivers) was developed. The importance of this map for forecasting the spreading of anthropogenic pollution in the channel of the Amur River is shown using the example of the emergency situation that resulted from the explosion at the chemical plant in the Sungari River basin (Jilin, China; November 2005). 相似文献
39.
Leaves of Dalembia jiayinensis sp. nov. are reported from the Santonian Yong'ancun Formation exposed along the Heilongjiang (Amur) River in Jiayin County, Northeast China. The leaves are compound, odd-pinnate, consisting of five leaflets. Leaflets are pinnately-lobed, trilobate or unlobed, elliptic, oblong, elliptic-rhomboid or ovate in outline, with blunt or rounded apex and the leaflet base is variable being cuneate, slightly decurrent, truncate or slightly cordate and sometimes asymmetric. Margin is entire or lobed. Lobes are short, simple, decreasing upwards, with wide and rounded sinuses. Apices of the lobes are usually rounded, sometimes notched. Venation is pinnate or palmately-pinnate, craspedodromous or semi-craspedodromous. The new species D. jiayinensis extends both the geographical and stratigraphic ranges of the genus Dalembia. This is the first occurrence of Dalembia in China and the most southern and youngest (Santonian) occurrence of this genus. 相似文献
40.
漠河盆地上侏罗统沉积特征与构造背景 总被引：2，自引：0，他引：2
对晚侏罗世漠河盆地的沉积特征进行了分析,并探讨了其构造类型和成因机制。详细的沉积学研究表明:晚侏罗世漠河盆地主要发育冲积扇、扇三角洲和湖泊相沉积,属于前陆盆地的陆相磨拉石部分。晚侏罗世漠河盆地的物源来自南北两个方向,具有典型前陆盆地双向物源特点:北部物源区是蒙古-鄂霍茨克造山带,位于西伯利亚板块南缘;南部物源区是下伏板块基底,位于大兴安岭北部。根据沉积特征、区域大地构造背景和俄罗斯上阿穆尔盆地有关资料认为:晚侏罗世漠河盆地为漠河-上阿穆尔前陆盆地的南半部分,形成和演化受蒙古-鄂霍茨克造山带制约;晚侏罗世二十二站期和额木尔河期是漠河盆地的主要成盆期,该时期湖泊面积广阔、暗色泥岩发育,是烃源岩的重要形成期。 相似文献