Biostratigraphy and Paleoecological Study of Pabdeh Formation in Interior Fars, Zagros Basin, Iran

• 作者: Ebrahim Ghasemi-Nejad Fatemeh Hadavi Manooseh P. Khavari Khorassani Reza Mousavi-Harami
• 来源期刊: 地质学期刊(英文)
• 学科: 医学
• 关键词: BIOSTRATIGRAPHY Pabdeh FORMATION ZAGROS Ecozone NANNOFOSSIL
• 年，卷（期）: dzxqkyw_2014,（11）
• 页码范围: 571-581
• 页数: 11页
• 分类号: R73

摘要

The Zagros basin, which trends NW-SE, is covered by a sea during the Paleogene, resulting in deposition of the Pabdeh Formation in the deeper parts of the basin. The thickness of the Pabdeh Formation in Tang-e-Abolhayat is about 221 m and it consists of purple shale at the base, gray shale, marl and marly limestone with a few horizons of nodular limestone toward the top. Seventy-two samples were collected and processed for nannofossil studies. Based on the identified nannofossil zones the age of the formation in Tang-e-Abolhayat is Late Paleocene-Late Oligocene (NP9-NP24). Changes in the abundance of different genera over the studied interval have resulted in identification of three ecozones: Ecozone 1 is characterized by oligotrophic conditions with an abundance of warm water taxa;Ecozone 2 marks when conditions became more eutrophic and the abundance of temperate taxa increased;Ecozone 3 represents a return to oligotrophic conditions with an increase in warm water taxa.