Paleoceanography and Paleobiogeography Patterns of the Turonian-Campanian Foraminifers from the Abderaz Formation, North Eastern Iran

• 作者: Abbas Sadeghi Meysam Shafiee Ardestani Mohammad Vahidinia
• 来源期刊: 地质学期刊(英文)
• 学科: 地球科学
• 关键词: Kopeh-Dagh Basin Abderaz FORMATION Planktonic FORAMINIFER MORPHOTYPE Sea Level Change PALAEOSALINITY
• 年，卷（期）: 2013,（1）
• 页码范围: 19-27
• 页数: 9页
• 分类号: P5

摘要

In this research, the Turonian-early Campanian sedimentary succession of the Abderaz Formation with 510 mthick (comprising: light grey shale and marls) was studied in the type section in eastern Kopeh-Dagh basin. The statistical analysis of the morphotype groups of the identified planktonic foraminifers shows that most of them are shallow water forms (SWF) and deep water forms (DWF). The high planktonic to benthic ratio indicates particular oligotrophic conditions and sedimentation in relatively deeper zones of a marine environment. The salinity of sea water during Coniacian was in the minimum level, whereas it reached maximum in Coniacian-Santonian boundary. Comparing Planktonic assemblages from the study formation with those from the Cretaceous biogeographical provinces reflects a close relationship between the identified species and the planktonic forms of the Tethyan provinces.