阿尔卑斯—喀尔巴阡上白垩统大洋红层特征与对比

Characteristics and correlation of Upper Cretaceous oceanic red beds in Alps-Carpathian area

在前人研究的基础上,从时代、岩性、古生物、沉积速率、沉积环境等方面对阿尔卑斯—喀尔巴阡地区的上白垩统大洋红层进行了详细对比,发现研究区内上白垩统大洋红层最早出露于Cenomanian期,最晚可延续至古近纪,且在Campanian期出露最为广泛,其岩性以灰岩、泥灰岩和含泥灰岩为主,生物化石以浮游有孔虫为主,沉积速率较低且在各地不尽相似,在CCD面上、下均可以出现,沉积环境一般是大陆边缘盆地、斜坡和大洋盆地等远洋、半远洋环境。通过比较分析,为进一步深入研究上白垩统大洋红层提供较为全面的基础资料。

In this paper, the Upper Cretaceous Oceanic Red Beds (CORBs) of the Alps-Carpathian area are analyzed in detail based on the previous data from publications. The data about 15 sections of CORBs are collected and carefully correlated from their ages, lithologies, paleontologies, sedimentation rates and paleoenvironments. The most of the sections locate in Italy, Austria, Poland, Slovakia and Romania, respectively. CORBs distributed in these countries are of many similar characteristics. They present from the Cenomanian in Scaglia Bianca formation in Italy, Pustelnia marl member and Macelowa marl member in Poland, and continue to the lower Palaeogene in Nierental formation in Austria. CORBs present in Campanian strata in all areas but Macelowa marl member. Most of them are formed by limestones, marls and marly limestones. In Nierental formation they are intercalated with turbidite succession. High carbonate content (>50%) and low TOC content is the common feature of CORBs in the study area. The planktonic foraminiferas are found as main fossils in these strata. The sedimentation rates of CORBs range from 1~4 mm/ka (shallow marine sediment of Pustelnia marl member and Macelowa marl member) to 10~35 mm/ka (Gura Belei formation, Romania), which are relatively low and vary in different locations. It cannot be directly connected with sediment color. CORBs can present either above the CCD or below. Generally, the palaeoenvironments range from continent margin basin, continental slope to deep oceanic basin. More detailed data about CORBs are presented in this paper as well.