缅甸英雄岛始新世-上新世浮游有孔虫及其古环境意义

英雄岛位于印度洋缅甸西海岸,前人在该区所做的工作较少,生物地层研究程度较低.围绕该区石油勘探的进行,作者分析了RM19-3-1井的29件钻井岩屑样品,根据所含浮游有孔虫识别出7次有孔虫生物事件.考虑到研究区处于低纬度地区,故采用Bolli和Saunders(1985)的分带标准建立了7个浮游有孔虫化石带:P12-P17带;P18/19-P21/N2带;P22/N3带,N4-N7带;N8-N10带;N11-N14带和N15-N20?带,其延限时代为始新世-上新世.根据所含有孔虫动物群的演替规律,可将研究区的沉积环境变化由下而上划分为6个阶段,总体具有大陆架-陆坡的沉积环境特征.

THE EOCENE-PLIOCENE PLANKTONIC FORAMINIFERA FROM RAMREE ISLAND, BURMA

The Ramree Island is located in the Indian Ocean and on the west coast of Burma. Previous work has provided little data about foraminifera and stratigraphy in that area. With the petroleum exploration the authors have processed 29 borehole cutting samples from the RM19-3-1 Well for the foraminiferal study. Eighteen genera and 83 species have been identified (including 17 undefined species, but only 4 important species have been listed in the table here). The study area situates in the low latitude, the present taxonomy is based on the criterion of Bolli and Saunders (1985), and 7 planktonic foraminiferal zones have been recognized as P12-P17, P18/19-P21/N2, P22/N3, N4N7, N8-N10, N11-N14 and N15-N20?, which are indicated by 7 bio-events. The zonation provides an age ranging from the Eocene to Pliocene to the studied interval. The succession of the foraminiferal faunas show 6 stages of sedimentary environmental changes from continental shelf to continental slope.