2013年 24卷 第2期
The Gujingling Section in Xiaodong, Guangxi Zhuang Autonomous Region, China, consists of cherts and siliceous siltstones, which belongs to the Bancheng Formation of the Qinzhou allochthon. Three successive radiolarian assemblage-zones related to the Guadalupian (Middle Permian) appear in the section in the following ascending order:...
The Machari Formation ranges from the ”upper Series 3” (Middle Cambrian) to Furongian (Upper Cambrian) in the Yeongwol area, Korea. It has been known to yield relatively diverse invertebrate fossils. Particularly, the trilobite biozones of the formation have been well defined. On the other hand, little has hitherto been studied on conodont microfossils for the formation.
This study provides the n-alkane and pollen records of the Holocene loess at Balong Town, Dulan County, Qinghai Province, and the environmental changes reconstructed from both records agreed well. Three stages of past climate change were deciphered by variations of the n-alkane and pollen proxies. Before 5 370 a BP, the climate was warm-dry
New data on a zonal structure of the Koupol deposit fahlores grains are given, and features of their chemism are shown. The fahlores chemical composition within the zones evolves from essentially arsenious (Fe-tennantite and Zn-tennantite), through mixed fahlores (Zn-tennantite-tetrahedrite arsenious and Zn-tennantite-tetrahedrite antimonous), to essential
ABSTRACT: The Suoerkuduke (索尔库都克) Cu (Mo) deposit, in the same metallogenic belt with Xilekuduke (希勒库都克) Cu-Mo deposit, is located in the Armantai (阿尔曼太) island arc belt on the northern margin of East Junggar, Northwest China. Rhenium and osmium isotopic analysis of seven molybdenite samples from the deposit was used to determine the age of mineralization. A seven-point isochron age of 317.7±7.6 Ma, which is consistent, within analytical error, with the average model age of 323.3±1.9 Ma indicates ...
The Zhenyuan gold orefield is located in the Ailaoshan gold belt, Sanjiang metallogenic region, China. The fluid inclusions (FIs) in mineralized quartz samples, collected from four deposits, i.e., Laowangzhai, Donggualin, Kudumu, and Daqiaoqing, in the orefield, were studied to reveal ore-forming process. Only aqueous-type and H2O-NaCl-type FIs were observed in the samples.
Wide distribution of Cambrian salt-bearing basins is a prominent feature of older strata in Asia. The Cambrian salt-bearing sequences are mainly distributed in East Siberia of Russia, Iran, Oman, India, Pakistan, and China. The Cambrian was one of the most important epochs of potash deposition in the world. Potash salts are found in East Siberia, Iran, India
Motivated by the potential flood outburst of Lake Gojal in the ungauged highly glacierized (27%) upper Hunza River Basin (HRB) in Pakistan that was dammed by a massive landslide on 4 January 2010, we attempt to analyze the characteristics of water inflow to the lake employing remote sensing data, two hydrological models, and sparsely observed data. One ...
This research uses eigenvalue characteristics of nonlinear principal component analysis (NLPCA) and principal component analysis (PCA) to investigate total electron content (TEC) anomalies associated with Taiwan’s Chi-Chi earthquake of 21 September 1999 (LT) (M-w=7.6). The transforms are used for ionospheric TEC from 01 August to 20 September 1999 (local time) using data from 13 GPS ..
Geofluid, driven by tectonic stress, can migrate and aggregate in geological body. Thus, numerical simulation has been widely used to rebuild paleo-tectonic stress field and probe oil/gas (one type of geofluid) migration and aggregation. Based on geological mapping, structural data, and mechanical parameters of rocks, we reconstruct the traces for gas/oil ...
Geochemical descriptors (carbon, nitrogen contents, and their isotopes) of sedimentary organic matter (OM) were investigated in the Pearl River estuary (PRE) and adjacent coastal waters. The comprehensive geochemical data of surface and deep sediments were provided, and the sources of sedimentary OM were discussed in this area mainly impacted by human
Chlorinated aliphatic hydrocarbons (CAHs), significant contaminants in groundwater, can be characterized by stable isotopic compositions of carbon and chlorine. Previously published methods were of low analytical sensitivity or not ideal for natural samples with low concentrations of CAHs. This method is reported here to carry out simultaneously carbon and chlorine
The Wenchuan earthquake triggered cascading disasters of landslides and debris flows that caused severe vegetation damage. Fracture zones can affect geodynamics and spatial pattern of vegetation damage. A segment tracing algorithm method was applied for identifying the regional fracture system through lineament extractions from a shaded digital