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    Late Paleocene Orthophragminae (foraminfera) from the Haymana-Polatli Basin, central Turkey) and description of a new taxon, Orbitoclypeus haymanaensis
    (MICROPALEONTOLOGY PRESS, 2001) Ozcan, E; Sirel, E; Altiner, SO; Colakoglu, S
    A transgressive shallow-marine succession suggested as a reference-section for early Thanetian by the 'Early Paleogene working group' (IGCP 286) was studied for its orthophragminid foraminifera from Haymana-Polath Basin in central Anatolia. Orthophragminae, closely associated with Assilina yvettae and Operculina heberti, have been identified in a friable clastic-carbonate sequence which contains Glomalveolina in its different horizons. Basinal sediments with planktonic taxa overlie the shallow-water deposits and preclude the study of orthophragminae higher in the succession. Orthophragminae, studied in oriented sections, were grouped into four categories considering the qualitative and quantitative aspects of megalospheric embryo and morphologic elements of equatorial and lateral chamberlets in equatorial and partly vertical sections. Thus, Discocyclina seunesi, Orbitoclypeus neumannae and Discocyclina sp.l have been identified and a new species, Orbitoclypeus haymanaensis, is erected. These assemblages were dated to Thanetian based upon the calcareous nannofossil and planktonic foraminifera identified in the overlying basinal sediments and also the benthonic foraminifera either associated with orthophragminae or present in different horizons of the shallow-marine succession.
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    Orthophragminid foraminiferal assemblages from an Ilerdian-early Cuisian reference section (Sakarya section, Haymana-Polatli Basin, central Anatolia-Turkey)
    (UNIV STUDI MILANO, 2003) Colakoglu, S; Ozcan, E
    The Sakarya section represents a highly fossiliferous part of the Haymana-Polath Basin succession (central Anatolia), consisting of mainly nummulitid, alveolinid and orthophragminid foraminifera. This section formerly proposed to serve as a reference section for early Ilerdian-early Cuisian Shallow Benthic Zones in Turkey by the 'Early Paleogene working group' was studied for its orthophragminid foraminifera, and a sequence of populations has been subjected to biometric analysis of the embryo and equatorial chamberlets. Discocyclina, which occurs throughout the section, is mainly represented by primitive specimens of Discocyclina archiaci, D. archiaci bakhchisaraiensis and Discocyclina sp.1 in the lowermost part, which is regarded as of middle Ilerdian age (orthophragminid zone 3). Upwards, different developmental stages of D. archiaci; transitional developmental stages of D. archiaci bakhchisaraiensis-staroseliensis and D. archiaci staroseliensis are accompanied sporadically by unribbed Orbitoclypeus, O. schopeni suvlukayensis and Discocyclina sp.1. This part of the section is regarded as middle-late Verdian in age (orthophragminid zone 4). A more diverse assemblage, represented by Nemkovella, Asterocyclina, ribbed and unribbed Orbitoclypeus accompanied by different Discocyclina species occurs in the uppermost part, which is thought to represent the transitional late Ilerdian-early Cuislan orthophragminid zones (orthophragminid zones 4/5). In these horizons, N. strophiolata fermonti, N. evae, primitive developmental stages of D. augustae sourbetensis, O. douvillei douvillei, D. fortisi fortisi, A. stella and O. munieri munieri are accompanied by D. archiaci staroseliensis, transitional developmental stages of D. arcbiaci staroseliensis-archiaci, O. scbopeni suvlukayensis and Discocyclina sp. 2. Biometric data allow refinements with respect to the stratigraphic ranges of some discocyclinid and orbitoclypeid foraminifera. This paper records the first descriptions of orthophragminids from the middle-late Ilerdian/early Cuislan marine deposits of Turkey.
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    The genera Lepidorbitoides and Orbitcoides: evolution and stratigraphic significance in some Anatolian basins
    (WILEY-BLACKWELL, 1999) Ozcan, E; Ozkan-Altiner, S
    Early ontogenetic morphologic features previously recognized as evolutionary parameters in Lepidorbitoides and Orbitoides have been tested in several flysch successions of Anatolia. Increase in embryo size (Li + ii), number of epi-embryonic chambers (E) and organization of embryonal chamber arrangement from 'quadrilocular' to 'bilocular' and multilocular in Orbitoides, increase in deuteroconch size (D), in deuteroconch-protoconch ratio (D/P) and in number of adauxiliary chambers (Ad) in Lepidorbitoides have been recognized as the main evolutionary trends, thus allowing the correlation of these features with time. The different developmental stages in Lepidorbitoides, i.e. L. pembergeri, L. campaniensis, L. bisambergensis, L. minor, L. socialis, and in Orbitoides, i.e. O. media, O. megaloformis, O. gruenbachensis, O. apiculata and O. gensacicus, have been described and illustrated based on the biometry of the populations. The values observed in some horizons, however, may not reflect the true phylogenetic stage of the orbitoidal taxa, especially in the species of Orbitoides, which usually show a wide variation of evolutionary parameters in the same population. A correlation scheme of phylogenetic development in Lepidorbitoides and Orbitoides with the planktonic foraminiferal zones is proposed. Lepidorbitoides populations with highly asymmetric 'quadriserial' nepionts occurring stratigraphically below the symmetric ones in Early Maastrichtian are thought to deserve a particular taxonomic status. In Orbitoides, a new embryonal chamber morphology previously undescribed from horizontal sections has been discovered. Copyright (C) 1999 John Wiley & Sons, Ltd.
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    The synthesis of four new bis(amino-p-chlorophenylglyoximes) and their polymeric complexes
    (MARCEL DEKKER INC, 1997) Pekacar, AI; Mercimek, B; Ozcan, E
    In this study, four new bis(amino-p-chlorophenylglyoximes), 1,2-phenylenebis(amino-p-chlorophenylglyoxime) L(1)H(2), 1,5-naphthylenebis(amino-p-chlorophenylglyoxime) L(2)H(2), 3,4-tolylenebis(amino-p-chlorophenylglyoxime) L(3)H(2), and 2,6-pyridylbis(amino-p-chlorophlenylglyoxime) L(4)H(2), have been synthesized from anti-p-chlorophenylchloroglyoxime and the corresponding aromatic diamines. Their polymeric complexes with Ni(II), Co(II) and Cu(II) have been prepered. The Ni(II) and Cu(II) complexes of these ligands have been found to be square-planar, while the Co(II) complexes are octahedral with water molecules as axial ligands. H-1 NMR, AAS, IR, magnetic susceptibility and elemental analytical data of the complexes and ligands are discussed.
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    Upper Cretaceous planktonic foraminiferal biostratigraphy from NW Turkey: calibration of the stratigraphic ranges of larger benthonic foraminifera
    (WILEY, 1999) Ozkan-Altiner, S; Ozcan, E
    Planktonic and larger benthonic foraminifers of the Upper Cretaceous (Santonian-Maastrichtian)-Lower Tertiary (Danian) rock units from north, northwest and central Anatolian fore-are basins have been investigated in order to improve the biostratigraphic resolution of this time interval. Total abundance and diversity of planktonic foraminifers vary from rare (the sequence from the Haymana region) to high (the sequences from the Cide, Caycuma, Hanonu and Yenikonak regions) and preservation is poor to moderate due to lithologic variation. First and last appearances of the planktonic foraminifera evaluated as major bio-events have been used to establish the biostratigraphic framework. Planktonic foraminiferal zonation from bottom to top of the succession consists of zones defined by Dicarinella concavata, Dicarinella asymetrica, Globotruncanita elevata, Globotruncana, ventricosa, Radotruncana calcarata, Globotruncanella havanensis, Globotruncana aegyptiaca, Gansserina gansseri, Abathomphalus mayaroensis and Morozovella pseudobulloides. Ten Orbitoides and Lepidorbitoides species have been identified. The different phylogenetic development stages of Orbitoides and Lepidorbitoides populations and other larger benthonic foraminifers, Pseudosiderolites vidali, Siderolites calcitrapoides, Siderolites denticulatus, Omphalocylus macroporus, Cideina sozerii, Hellenocyclina beotica, and Clypeorbis mamillata have been calibrated with the planktonic foraminiferal zonation established in the same successions. Hence, an integrated zonational scheme composed of planktonic foraminifers and larger benthonic foraminifers has allowed a detailed stratigraphy of these successions to be erected. Copyright (C) 1999 John Wiley & Sons, Ltd.