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981.
982.
1 Introduction According to recent researches, the North China Craton consists of three parts: the eastern block, western block and central zone (Zhao, 2001; Wilde et al., 2002). Paleoarchean continental blocks and zircon residuals have only been found in a few regions, such as Anshan, East Liaoning (Liu et al., 1992; Song et al., 1996; Wan et al., 2002, 2005), Caozhuang, East Hebei (Liu et al., 1992) and Xinyang, West Henan (Zheng et al., 2004), which are mainly distributed in the east… 相似文献
983.
ZHANG Jiheng GE Wenchun WU Fuyuan LIU Xiaoming College of Earth Sciences Jilin University Changchun Jilin Institute of Geology Geophysics Chinese Academy of Sciences Beijing Key Laboratory of Continental Dynamics 《《地质学报》英文版》2006,80(1):58-69
1 Introduction Mesozoic volcano-intrusive rocks are widely distributed in the Da Hinggan Range of northeastern China, and are considered as one of the most spectacular geological sights in eastern Asia. Recently, studies on granites with high εNd(t) values and Phanerozoic crustal growth in the Centra Asian Orogenic Belt have greatly promoted fundamental research into the geology of this area (Jahn et al., 2000, 2001, 2004; Wu et al., 2000, 2002, 2003). However, work on the eruption time,… 相似文献
984.
MO Jinyou WANG Wei HUANG Zhitao HUANG Xin XU Xing 《《地质学报》英文版》2006,80(4):486-489
Based on a partial postcranial skeleton collected from the Lower Cretaceous Napai Formation of Guangxi, China, we erect a new sauropod taxon, Fusuisaurus zhaoi gen. et sp. nov. The holotype specimen consists of the left ilium, left pubis, anterior caudals, most of the dorsal ribs and distal end of the left femur. Fusuisaurus zhaoi is diagnosed by a unique combination of character states among the known sauropods. It displays several synapomorphies of Titanosauriformes but lacks many derived features seen in other titanosauriforms, suggesting that the new taxon represents the basalmost known titanosauriform and providing new evidence that Titanosauriformes originated from Asia. A size comparison suggests that Fusuisaurus zhaoi is among the largest Early Cretaceous sauropods, providing an important addition to the Early Cretaceous Chinese sauropod diversity. 相似文献
985.
1 Introduction The Gaojiacun intrusive complex is one of the numerous ultramafic-mafic intrusions in Sichuan Province of China. It was mapped during the 1970s and studied mainly by Chinese scientists (e.g. Geological Team 106, 1975; Shen et al., 1986, 1989; CGGJC, 1986; Yang et al., 1993; Li et al., 1995; Shen et al., 2003; Zhu et al., 2004a). Since the year 2000, China has become one of the largest PGE consumers. While the country can produce only less than 1 ton PGE/year, the Chin… 相似文献
986.
The First Mesozoic Heterodactyl Bird from China 总被引:1,自引:1,他引:0
ZHANG Zihui HOU Lianhai HASEGAWA Yoshikasu Jingmai O'CONNOR Larry D. MARTIN Luis M. CHIAPPE 《《地质学报》英文版》2006,80(5):631-635
1 Introduction Enantiornithines were the dominant birds nearly worldwide throughout the entire span of the Cretaceous (Chiappe, 1995; Feduccia, 1996). The adaptive radiation of opposite birds is little known besides the disparity of rostral morphology in Boluochia (Zhou, 1995), Longipteryx (Zhang et al., 2001), Longirostravis ( Hou et al., 2004), and the presence of stomach contents that reflect a diversity of diets. Like the structure of rostrum, differentiation of the locomotor apparatu… 相似文献
987.
中国西南喀斯特地区石漠化成因及防治初探 总被引:6,自引:0,他引:6
喀斯特地区石漠化,是我国西南地区生态环境最突出的问题。首先探讨我国西南地区喀斯特石漠化成因,主要有自然因素和人为因素两方面的原因,指出喀斯特石漠化引起的干旱缺水、土壤贫瘠、地质灾害等严重威胁当地人民的生产和生活;据此,提出防治喀斯特石漠化的基本措施,即缓解人口压力、加快生态建设、调整产业结构与布局等。 相似文献
988.
城镇化是西北地区发展的必由之路,然而最大的自然障碍因素是水资源严重短缺。国外较早地开展并已有效地利用了城市雨水,而我国起步比较晚。西北地区在推进城镇化建设中,宜把城市雨水资源化作为城市节水的方向之一。城市雨水资源的利用对西北地区城市可持续发展有重要的意义。 相似文献
989.
The giant Dahutang tungsten (W) deposit has a total reserve of more than 1.31 Mt WO3. Veinlet-disseminated scheelite and vein type wolframite mineralization are developed in this deposit, which are related to Late Mesozoic biotite granite. Four major types of alterations, which include albitization, potassic-alteration, and greisenization, and overprinted silicification developed in contact zone. The mass balance calculate of the four alteration types were used to further understanding of the mineralization process. The fresh porphyritic biotite granite has high Nb, Ta, and W, but low Ca and Sr while the Jiuling granodiorite has high Ca and Sr, but low Nb, Ta, and W concentrations. The altered porphyritic biotite granite indicated that the Nb, Ta, and W were leached out from the fresh porphyritic biotite granite, especially by sodic alteration. The low Ca and Sr contents of the altered Neoproterozoic Jiuling granodiorite indicate that Ca and Sr had been leached out from the fresh granodiorite by the fluid from Mesozoic porphyritic biotite granites. The metal W of the Dahutang deposit was mainly derived from the fluid exsolution from the melt and alteration of W-bearing granites. This study of alteration presents a new hydrothermal circulation model to understand tungsten mineralization in the Dahutang deposit. 相似文献
990.