作 者:刘治成,张廷山,魏祥峰 |
单 位:西南石油大学资源与环境学院 |
基金项目: |
摘 要: |
在赤水地区嘉陵江组中共发现遗迹化石4 个属8 个种,其中有3 个未定种,即Palaeophycus tubularis(管状古藻迹),Palaeophycus curvatus(弯曲古藻迹),Palaeophycusisp.A (古藻迹未定种A),Palaeophycus isp.B(古藻迹未定种B), Planolites octichnus(八曲漫游迹),Helminithopsis abeli(阿伯尔拟蠕形迹),Helminithopsis isp(似蠕虫迹未定种),Phycodes pedum(足状拟藻迹)。这些遗迹化石主要为无脊椎动物的觅食迹和进食迹,其中多数为下浮雕保存,其次为上浮雕保存,少数为全浮雕保存。根据遗迹相组合特征,结合沉积相分析,可划分出两个遗迹组合院Palaeophycus 遗迹组合,代表的是水体较浅、受短期海平面变化影响较大的灰岩坪沉积环境;Planolites要Helminithopsis 遗迹组合,代表 的是与Palaeophycus 遗迹组合相比水体较深、能量较低的开阔海台地的台内洼地环境。 |
关键词:四川盆地;赤水地区;嘉陵江组;遗迹化石;沉积环境 |
Author's Name: Liu Zhicheng, Zhang Tingshan, Wei Xiangfeng |
Institution: Faculty of Resource & Environment, Southwest Petroleum University |
Abstract: |
Some Lower Triassic ichnofossils are first discovered in Chishui area, the southern part of Sichuan Basin. These fossils are attributed to 4 ichnogeneras and 8 ichnospecies, including 3 ichnospecies indeterminated, in Jialingjiang Formation, namely ,isp.A,isp.B, ,isp and pedum. All of these ichnofossils chiefly are invertebrate fodinichnia and agrichnia, in which the majority is preserved as hyporelief, the next as epirelief and the minority as full relief. According to the characteristics of ichnofacies assemblages, combined with the analysis of sedimentary facies,these fossils can be divided into two ichnoassemblags: (1)ichnoassemblage,representing the depositional environment of limestone flat during shallow water effected by short term change of sea level. (2) ichnoassemblage, representing the depositional environment of innerdepression within open sea platform with lower energy during deeper water than that of the ichnoassemblage. |
Keywords: Lower Triassic; Jialingjiang Formation; Ichnofossil; Sedimentary; Sichuan Basin |
投稿时间: 2008-02-24 |