Naslov
Biostratigraphical, lithological and paleoecological aspects of the Upper Cretaceous deposit from the Palmyride Area, Syria

Autori
Pecimotika, Gabrijela ; Cvetko Tešović, Blanka ; Premec Fuček, Vlasta

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Abstract Volume / Marchant, M. ; Hromic, T. - Lahti : Grzybowski Foundation, 2014, 114-115

ISBN
978-83-88927-35-5

Skup
International Symposium on Foraminifera, FORAMS 2014, Chile

Mjesto i datum
Čile, 19.01.2014. - 24.01.2014

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
Planktonic foraminifera; Biostratigraphy; Phosphatic grains; Upper Turonian–Maastrichtian

Sažetak
This study represents a detailed micropaleontological investigation of planktonic foraminiferal assemblages from the Upper Turonian to Maastrichtian interval of two deep exploration wells (Al Mahr-1 and Palmyra-1) in the Palmyride area of Syria. The investigated strata are divided into three units: 1) the upper part of the Judea Formation (Upper Turonian–Coniacian) ; 2) the Soukhne Formation (Santonian–Lower Campanian) ; and 3) the Shiranish Formation (Upper Campanian–Maastrichtian). The presence of rich and highly diverse foraminiferal associations enabled biostratigraphical zonation of the Upper Turonian to Maastrichtian deposits based on the presence of index-taxa and/or the entire microfossil assemblages. The results represent the first detailed biostratigraphic zonation based on planktonic foraminifera from the Palmyride area. Nine biozones have been established: 1) Dicarinella concavata Zone ; 2) Dicarinella asymetrica Zone ; 3) Globotruncanita elevaata Zone ; 4) Contusotruncana plummerae Zone ; 5) Radotruncana calcarata Zone ; 6) Globotruncanella havanensis Zone ; 7) Pseudoguembelina palpebra Zone ; 8) Racemiguembelina fructicosa Zone and 9) Abathomphalus mayaroensis Zone. The biostratigraphic zonation is compared with the standard zonation. Documenting changes in planktonic foraminiferal assemblages and lithological alterations are critical for paleoclimatic and paleooceanographic interpretations. The late Turronian to early Campanian foraminiferal assemblages (biozones I-III) suggest tropical to subtropical climate and deposition in outer shelf environments. The well-preserved and highly diversified late Campanian to early Maastrichtian foraminiferal assemblages (biozones IV-IX) imply a well-stratified water column while the lithological characteristics of the deposits indicate outer shelf to upper bathyal environments. A decrease in the number of planktonic species during the late Maastrichtian indicates cooling and deterioration of paleoceanographic conditions. Phosphate grains are present in the Soukhne Formation (Santonian–Lower Campanian) and are an important indicator of specific geological and paleoenvironmental conditions, such as oxygen deficiency, upwelling and transgression. The results of this detailed stratigraphic analysis, including biostratigraphy and litostratigraphy, provided insights into the nature of deposition along the northern passive margin of Gondwana during the Cretaceous, and the determinations of the composition and diversity of foraminiferal assemblages allowed important new paleoecological and paleoclimatic interpretations.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA