浙江永康盆地朝川组泥灰岩段沉积特征及其古气候意义

位于浙江省东部的永康盆地是典型的白垩纪陆相红盆.本文作者发现在永康盆地北东部的朝川组红层沉积中发育较深水暗色泥灰岩沉积,与较浅水红色细碎屑沉积呈互层或夹层产出,具渐变式湖相碳酸盐岩与陆源碎屑岩混合沉积的特征.控制该混合沉积形成的主要因素是湖盆浪基面之下的静水环境及干旱与潮湿气候的交替变化.通过对朝川组泥灰岩段沉积环境及成因进行分析,结合该泥灰岩段中保存的孢粉和植物化石组合,笔者认为该套湖相碳酸盐岩与陆源碎屑岩的混合沉积反映了浙东地区早白垩世晚期总体可能处于干热气候环境,但存在短时间内的干湿气候交替.

Sedimentary characteristics and paleoclimatic significance of marl section from Chaochuan Formation in Yongkang Basin,Zhejiang Province

Yongkang Basin is a typical Cretaceous terrestrial red basin in eastern Zhejiang Province. Authors of the paper discovered that in the red beds of the Chaochuan Formation at the northeast part of the Yongkang basin there are developed deep-water facies dark marl sediments occurred as interbeds in the shallow-water facies red fine-grained clastic sediments, showing characteristics of mixed sediments of gradually varied lacustrine facies carbonatites and terrigenous facies clastic rocks. The main factors controlling the formation of the mixed sediments are the standing-water environment below the wave base and alternating change of dry and humid climate. Basing on the analyzing sedimentary environment and genesis of the marl section of the Chaochuan Formation, the authors consider that the mixed sediments reflect a xerothermic paleoclimate environment with short-time change of dry and humid climates in which the eastern Zhejiang Province was situated during the Cretaceous.