The conglomerates developed in the Middle-Upper Devonian of the Fengxian-Shanyang area,Shaanxi Province, include mud conglomerates, dolostone conglomerates, ore conglomerates, and albite conglomerates. These conglomerates are closely associated with hydrothermal sedimentary bodies in space. Their petrochemical compositions were also affected by hot water activity. The petrological and petrochemical characteristics indicate that the formation of these conglomerates was controlled by growing faults during the metallogenic epoch. These growing faults not only resulted in the formation of the deep water basin where the conglomerates were deposited as a result of deep water mass flows, but also carrying heat flows for the mineralisation of these conglomerates. The lead-zinc deposits are products of the synsedimentary hydrothermal sedimentation. Through studying petrology and petrochemistry (including isotope dating) of mud conglomerates in the Chigou formation (D2ch), the author suggests that the hydrothermal ore deposit series (siderite-silver-multi-metal-gold deposits) in the Daxigou formation (D2d) are of natures of secondary hydrothermal sedimentation.
About author: Duanmu Heshun, born in 1960, graduated from Lanzhou Institute of Geology, Academia Sinica and has obtained his Master degree in 1987. Now he is a lecturer in the Department of Material Engineering, Xi'an University of Science & Technology, and is mainly working on Petrological research.
Cite this article:
. THE CONGLOMERATES IN THE MIDDLE-UPPER DEVONIAN OF THE FENGXIAN-SHANYANG,SHAANXI PROVINCE[J]. JOURNAL OF PALAEOGEOGRAPHY, 2000, 2(3): 92-98.
. THE CONGLOMERATES IN THE MIDDLE-UPPER DEVONIAN OF THE FENGXIAN-SHANYANG,SHAANXI PROVINCE[J]. JOPC, 2000, 2(3): 92-98.
[1]曾允孚,夏文杰.沉积岩石学。北京:地质出版社,1984.106-109
[2]王俊发,张复新,炎金才,陈苓.秦岭泥盆系层控金属矿床.西安:陕西科技出版社,1991.9-14
[3]杨志华.边缘转换盆地的构造岩相与成矿.北京:科学出版社,1991.18-38,80-87
[4]梅志超,孟庆任.秦岭造山带的沉积体系与古地理格局演化.古地理学报,1999(1):33-39
[5] Rust B.R. Pebble orientation in fluvial sediments. J. Sediment. Ptrol., 1972,42:384-388
[6] Gloppen T. G. and Steel R. The deposits, internal structure and geometry in six alluvial fan-fan delta bodies (Devonian-Norway), a study in the significance of bedding sequence in conglomerates. Soc.Econ.Paleontal.,Spec.Publ.1981,31:49-69
[7]涂光炽.中国层控矿床地球化学,第3卷.北京:科学出版社,1988 131-168
[8]端木合顺.凤太矿田“三位一体”成矿环境模式. 1996.西北大学学报(增刊)