Biostratigraphic, isotopic, and petrologic data from the Central Pontides document major southward growth of the Eurasian continental crust by subduction-accretion during the Cretaceous and Triassic Periods. A major part of the accreted material is represented by a crustal slice, 75 km long and up to 11 km thick, consisting of metabasite, metaophiolite, and mica schist that represent underplated Tethyan oceanic crustal and mantle rocks. They were metamorphosed at 490 °C and 17 kbar in mid-Cretaceous time (ca. 105 Ma). The syn-subduction exhumation occurred in a thrust sheet bounded by a greenschist facies shear zone with a normal sense of movement at the top and a thrust fault at the base. A fl exural foreland basin developed in front of the south-vergent high-pressure-low-temperature (HP-LT) metamorphic thrust sheet; the biostratigraphy of the foreland basin constrains the exhumation of the HP-LT rocks to the Turonian-Coniacian, ~20 m.y. after the HP-LT metamorphism, and ~25 m.y. before the terminal Paleocene continental collision. The Cretaceous subduction-accretion complex is tectonically overlain in the north by oceanic crustal rocks accreted to the southern margin of Eurasia during the latest Triassic-earliest Jurassic. The Triassic subduction-accretion complex is made up of metavolcanic rocks of ensimatic arc origin and has undergone a high pressure, greenschist facies metamorphism with growth of sodic amphibole. Most of the Central Pontides consists of accreted Phanerozoic oceanic crustal material, and hence is comparable to regions such as the Klamath Mountains in the northwestern United States or to the Altaids in Central Asia.

Biostratigraphic, isotopic, and petrologic data from the Central Pontides document major southward growth of the Eurasian continental crust by subduction-accretion during the Cretaceous and Triassic Periods. A major part of the accreted material is represented by a crustal slice, 75 km long and up to 11 km thick, consisting of metabasite, metaophiolite, and mica schist that represent underplated Tethyan oceanic crustal and mantle rocks. They were metamorphosed at 490 °C and 17 kbar in mid-Cretaceous time (ca. 105 Ma). The syn-subduction exhumation occurred in a thrust sheet bounded by a greenschist facies shear zone with a normal sense of movement at the top and a thrust fault at the base. A fl exural foreland basin developed in front of the south-vergent high-pressure-low-temperature (HP-LT) metamorphic thrust sheet; the biostratigraphy of the foreland basin constrains the exhumation of the HP-LT rocks to the Turonian-Coniacian, ~20 m.y. after the HP-LT metamorphism, and ~25 m.y. before the terminal Paleocene continental collision. The Cretaceous subduction-accretion complex is tectonically overlain in the north by oceanic crustal rocks accreted to the southern margin of Eurasia during the latest Triassic-earliest Jurassic. The Triassic subduction-accretion complex is made up of metavolcanic rocks of ensimatic arc origin and has undergone a high pressure, greenschist facies metamorphism with growth of sodic amphibole. Most of the Central Pontides consists of accreted Phanerozoic oceanic crustal material, and hence is comparable to regions such as the Klamath Mountains in the northwestern United States or to the Altaids in Central Asia.

Upper Permian marine carbonates are distinguished in two contrasting biofacies belts in Turkey. The Southern Biofacies Belt, represented by low-energy inner platform deposits of the Tauride Belt and the Arabian Platform, is rich in algae and smaller foraminifera but poor in fusulines. The Kubergandian and Murgabian stages are missing, although the rest of the Upper Permian consists of monotonous, shallow-marine carbonate deposits. The extremely tectonised and fragmented Northern Biofacies Belt includes the Upper Permian of the Karakaya Orogen and outer platform or platform margin deposits of the Tauride Belt. These deposits are rich in parachomata-bearing fusulines comprising Cancellina, Verbeekina, Afghanella, Sumatrina, Neoschwagerina and Yabeina. The reconstructed biostratigraphic scheme indicates that all Upper Permian stages (Kubergandian-Dorashamian) are present.The lateral continuity of the two biofacies belts is detected by the presence of tongues of he Northern Biofacies Belt pinching out in the Southern Biofacies Belt. Upper Permian blocks in the Karakaya Orogen display similar palaeontologic and biofacies characteristics, with the outer platform or platform margin deposits of the Taurides constituting the northernmost extension of the carbonate platform. This platform was probably facing a basin or a trough to the north. The lack of any transgressive Upper Permian deposits resting unconformably on the pre-Permian basement of the Sakarya Continent strongly suggests that such a basin was located between the Late Permian carbonate platform in the south and the basement rocks of the future Sakarya Continent in the north.

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The Aladag Unit is one of the main tectonic units in the Tauride Belt, located in southern Turkey. It includes a continuous Paleozoic carbonate sequence encompassing the mid-Carboniferous boundary, with outcrops being especially well exposed in the Hadim region. The boundary succession lithology is mainly composed of carbonates with intercalated quartz arenitic sandstone layers. Based on foraminifers, four biostratigraphic zones have been defined in the interval from the Upper Serpukhovian to the Lower Bashkirian. These zones are, in ascending order: the Eostaffella ex gr. ikensis-E. postmosquensis Zone (Zapaltyubinsky Horizon, Upper Serpukhovian); the Plectostaffella jakhensis-P. bogdanovkensis Zone, and the Millerella marblensis Zone (Bogdanovsky Horizon, lower Bashkirian); and the Semistaffella sp. Zone (Syuransky Horizon, lower Bashkirian). The mid-Carboniferous boundary occurs between the Eostaffella ex gr. ikensis-E. postmosquensis Zone and the Plectostaffella jakhensis-P. bogdanovkensis Zone. Boundary beds are characterized by eight, repeatedly occurring microfacies types, namely: (1) coated crinoidal packstone; (2) coated bioclastic grainstone; (3) oolitic grainstone; (4) oolitic packstone-grainstone; (5) intraclastic grainstone; (6) mudstone-wackestone; (7) quartz-peloidal packstone; and 8) quartz arenitic sandstone. Based on microfacies stacking patterns, various types of shallowing-upward cycles have been recognized. Depositional sequences and sequence boundaries are correlatable with those described from North America and Russia and Carboniferous global sea-level curves. The duration of cycles has been estimated as 100 ky, suggesting that cycle periodicities correspond to the Milankovitch eccentricity band.

The Cretaceous-Paleogene (K/Pg) boundary in the Haymana Basin, Central Anatolia, Turkey, was delineated using planktonic foraminiferal biostratigraphy, microfacies analysis, and sequence stratigraphy. An , 29 m outcrop consisting of limestone and marl was measured, and four planktonic foraminiferal biozones were identified spanning the boundary. Planktonic foraminiferal extinction across the K/Pg boundary was catastrophic and abrupt. The extinction level is overlain by a unit (Zone P0) showing an increase in echinoid fecal pellets and authigenic clay minerals such as glauconite, suggesting low sedimentation rates in the early Danian. Ten microfacies types were identified indicating inner-ramp to basinal paleoenvironments based on the sedimentological characteristics and microfossil and macrofossil assemblages. Maastrichtian carbonates contain large benthic foraminifera, calcareous red algae, bryozoans, fragments of echinoderms and mollusks, and planktonic foraminifera. Overlying Maastrichtian-Danian silty marls and silty limestones have common planktonic and benthic foraminifera. Progradation of carbonates into the basin took place during the highstand systems tract, and deposition of a silty marl succession occurred during the transgressive systems tract. The K/Pg boundary is in the upper part of the transgressive systems tract, below a maximum flooding surface. Sequence stratigraphic analysis of a second section, Campo Pit, New Jersey, USA, showed that the K/Pg boundary occurs within a transgressive systems tract in New Jersey as well, suggesting a global sea-level rise across the K/Pg boundary.

Planktonic and larger benthonic foraminifers of the Upper Cretaceous (Santonian–Maastrichtian)‐Lower Tertiary (Danian) rock units from north, northwest and central Anatolian fore‐arc 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, Çaycuma, Hanönü 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, Omphalocyclus macroporus, Cideina sözerii, 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 © 1999 John Wiley & Sons, Ltd.

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