Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2014
Öğrenci: ALEV GÜRAY
Danışman: SEVİNÇ ALTINER
Özet:The Paleocene-Eocene sequences are widely distributed around onshore and offshore Black Sea. When the previous studies in the Turkish coasts of the Black Sea are considered, the deficiency of a detailed biostratigraphical framework attracts the attention. The taxonomy of the planktonic foraminifera and the benthic foraminifera assemblages are important for the establishment of the new biostratigraphical frame in the Paleocene-Eocene sequences of the Western and Central Black Sea regions. The Paleocene-Eocene interval was studied throughout the sequences including Akveren, Atbaşı and Kusuri formations. Taxonomical studies have been carried out on 327 samples collected from 9 stratigraphical sections for the high resolution biostratigraphy. 4 families, 18 genera, 87 species have been identified for the planktonic foraminifera and 30 families, 38 genera, 14 species were defined for the benthic foraminifera. By using the first and last occurrences of the planktonic foraminifera, 13 biozones and 4 subzones have been established in this study: (1) Parvularugoglobigerina eugubina-Praemurica uncinata Interval Zone (with Subbotina triloculinoides-Praemurica inconstans Interval Subzone and Praemurica inconstans-Praemurica uncinata Interval Subzone), (2) Praemurica uncinata-Morozovella angulata Interval Zone, (3) Morozovella angulata-Acarinina nitida Interval Zone, (4) Acarinina nitida-Globanomalina pseudomenardii Concurrent Range Zone, (5) Morozovella velascoensis Partial-range Zone, (6) Morozovella subbotinae Partial-range Zone (with Morozovella edgari Partial-range Subzone and Morozovella formosa/Morozovella lensiformis-Morozovella aragonensis Interval Subzone), (7) Morozovella aragonensis-Morozovella formosa Concurrent-range Zone, (8) Acarinina pentacamerata Partial-range Zone, (9) Acarinina cuneicamerata-Hantkenina spp. Interval Zone, (10) Hantkenina spp.-Acarinina boudreauxi Concurrent-range Zone, (11) Globigerina eoceanica Partial-range Zone, (12) Globigerina turkmenica-Globigerina azerbaidjanica Concurrent-range Zone and (13) Globigerina azerbaidjanica-Acarinina medizzai Interval Zone. The Paleocene-Eocene boundary has been recognized by the first occurrences of Acarinina wilcoxensis and Acarinina pseudotopilensis in Erfelek 1 and Kaymakam Kayası sections. Response of planktonic foraminifera to the environmental perturbations during the Paleocene-Eocene Thermal Maximum (PETM) is recorded by the absence of the excursion taxa (Acarinina sibaiyaensis, Acarinina africana and Morozovella allisonensis) besides the scarcity or absence of the other warm water surface dwellers during the latest Paleocene-earliest Eocene. The benthic foraminiferal extinction event, which is another important event on the boundary, is recorded by the extinction of Pullenia coryelli below the boundary in the Erfelek 1 Section. The XRD studies on the Erfelek 1 Section have recorded two levels for the carbonate dissolution during the PETM, whereas the clay mineralogy indicates different sources for the clay minerals, which show the effect of the tectonism in the region. The discrepancies in the stratigraphical ranges of the planktonic foraminifera have been recognized especially during the Middle and Late Eocene for the Black Sea region. These differences with respect to Mediterranean and Crimean-Caucasus realms emphasize the importance of the paleogeographical position of the Black Sea Region, as the connection between those two regions, to revise and recalibrate marker planktonic foraminiferal bioevents for the Black Sea region.