西秦岭造山带泥盆纪沉积地质学和动力沉积学研究:西秦岭南带泥盆纪裂陷槽盆地、摩天岭地体沉积特征和盆地格局

南秦岭裂陷槽位于中秦岭微板块和摩天岭地体之间．本文根据裂陷槽盆地三河回群和摩天岭地体泥盆系沉积学研究，结合火山作用和生物古地理的研究，探讨该区泥盆纪的盆地格局．三河口群以深水盆地和陆棚沉积为主，内夹拉斑玄武岩和硷性玄武岩，岩石化学和稀土元素的分配型式都反映其处于裂陷槽盆地背景。生物古地理分异也指示型陷槽盆地的存在．摩天岭地体泥盆系为滨岸－陆棚碎屑岩和陆棚－缓坡碳酸盐沉积，其为扬子板块北部大陆边缘的一部分．

SEDIMENTARY GEOLOGY AND DYNAMIC SEDIMENT-OLOGY OF THE DEVONIAN STRATA IN THE WEST QINLING OROGENIC BELT: SEDIMENTARY CHARACT-ERISTICS AND FRAMEWORK OF THE DEVONIAN RIFT TROUGH AND MOTIANLING TERRANE IN THE SOUTHERN BELT OF THE WEST QINLING OROGENIC BELT

The southern Qinling rift trough is installed between the Qinling mlcroplate and Motianling terrane.The stress in this article is put on the stratigraphy,sedimentology,volcan ism and palaeobiogeography of the Devonian strata in the rift trough and Motlanling ter rane,as well as tneir depositional systems and basin framework.The Devonlan Sanhekou Group in the rift trough consists of metamudstone,silty mudstone and thin-to thick-bed ded lime mudstone in deep-water basin and shelf environments interstratified with tholeiite and alkali basalt.The chemical analysis and REE distribution patterns of tholellte and al kali basalt indicate the existance of the rift trough during Devonlan time.TheDevonian strata in the Motianling terrane are made up of terrigenous nearshore and shelf deposition al system,and carbonate ramp and shelf depositional systems. The terrane is interpreted as part of the northern continental margin of the Yangtze Plate.