赣西北三叠系研究的新进展

NEW PROGRESS IN THE STUDY OF THE TRIASSIC IN NORTHWESTERN JIANGXI

分布于赣西北地区的三叠系嘉陵江组,以往虽未获充分的化石资料,但长期以来把它划归中三叠统。作者在1∶5万区调工作中,实测了嘉陵江组的地层剖面,按其岩性自下而上划分为四个岩性段,并首次采获牙形刺化石有:Naohindeodella cf.triassica,Pachycladina cf.Obliqua,P.cf.Sanxiaensis,Hadrodontina sp.,Loncho lina cf.hubeiensis,Furnishius?sp.等,以上牙形刺的属、种均为早三叠世奥伦期的重要分子。据此,作者将该地区嘉陵江组改属下三叠统上部的一个组。

The Jialingjiang Formation distributed in northwestern Jiangxi has long been assigned to the Middle Triassic though no adequate fossil data have been obtained. Jn the 1:50000 scale regional surveys the authors measured a stratigraphic section of the Jialingjiang Formation and divided the formation into four lithologic members according to the lithology. They for the first time collected conodont fossils: Neohindeodella cf. trassica, pachycladina cf. obiqua, P. cf. sanxiaensis, Hadrodontina sp., Lonchodina cf. hubeiensis and Fnrishiussp. The above-mentioned conodont general and species are all important elements of Olenekian (Warly Triassic) age. According to this, the authors consider that the Jialingjiang Formation should belong to a formation in the upper part of the Lower Triassic.