摘要
广西石炭系大致可分为四个沉积区,三种沉积类型,即近岸滨海—浅海沉积型、台沟相沉积和远岸碳酸盐台地相沉积等。以上三种类型的沉积柳州地区都可见到。柳州地区的上、下石炭统界线,也有碎屑岩相和碳酸盐相两种类型。 本文还介绍了7个有代表性的地质考察点和剖面,通过这些考察点,可以看到沼泽与淡化泻湖相,台地生物滩相,台地前缘斜坡相等多种类型的沉积和两种类型上,下石炭统界线,这些考察点交通方便,实为地质考察和教学实习的极佳场所。
There were roughly four sedimentary areas and three sedimentary types in Guangxi during the Carboniferous. The first type is the littoral-neritic facies near seashore, which is distributed in Area Ⅰ and Ⅳ; the second type is the trench facies in platform, mainly in area Ⅱ ; the third type is carbonate platform facies far away from seashore, chiefly in Area Ⅲ (Fig.1).
The Liuzhou area, where three sedimentary types mentioned above have been recognized, is located between Area Ⅱ and Ⅲ.
The Lower - Middle Carboniferous boundary in the vicinity of Liuzhou is well exposed and rich in fossils, and two sedimentary types have been found, i.e., clastic rock facies and carbonate facies.
This paper also describes seven selected sites and sections for geological field trip, where can be seen various sedimentary types such as shoreline clastic rock facies, coastal swamp and fresh lagoon facies, carbonate platform facies, organic bank of platform facies, semi-restricted platform facies, platform front slope and trench margin in platform. As traffic is quite convenient at the sites and sections, they are ideal places for geological field trip and teaching practice of geology.
