Similarities and Differences of Orbitoides & Omphalocyclus Microspheric Forms with Selected Examples from Northern Iraq and Turkey and Their New Morphometric Data


GÖRMÜŞ M., Al Nuaimy Q. A., Meric E.

1st Springer Conference of the Arabian-Journal-of-Geosciences (CAJG), Hammamet, Tunus, 12 - 15 Kasım 2018, ss.37-40 identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Doi Numarası: 10.1007/978-3-030-01452-0_9
  • Basıldığı Şehir: Hammamet
  • Basıldığı Ülke: Tunus
  • Sayfa Sayıları: ss.37-40
  • Anahtar Kelimeler: Aqra Formation, N Iraq, Turkey, Orbitoides, Omphalocyclus, Biometry
  • Ankara Üniversitesi Adresli: Evet

Özet

Aqra Formation sediment outcrops are widespread in the northern Iraq. There are different formations in various localities of Turkey which contain rich Orbitoides and Omphalocyclus genera. Megalospheric (A) forms are particularly predominant in the Campanian-Maastrichtian aged siliciclastic and carbonate sediments. External and internal parameters of both genera are correlated in selected specimens to bring out differences and similarities especially on microspheric forms of Orbitoides and Omphalocyclus. New morphometric data on more than one hundred individual equatorial thin sections from the carbonate samples of the Aqra Formation show that microspheric individuals of Omphalocyclus include semicircular equatorial chamberlets at the initial part. On later parts thick walled rectangular shaped chamberlets are shown. In contrast, microspheric individuals of Orbitoides mainly comprise semicircular and semi rectangular equatorial chamberlets. Biometrical data on the Orbitoides tests from the Aqra Formation show population abundance of Orbitoides megaloformis and O. gruenbachensis.