Planktonic foraminifera were quantitatively analyzed across the Santonian succession and their boundaries at the Jebel Ennahli and Ettout sections, northern Tunisia. The continuous sedimentary succession is dominated by hemipelagic facies, allowing a good biostratigraphic correlation for this time interval. Fifty-fi fe planktonic foraminiferal species belonging to 13 genera have been identifi ed. The distribution pattern of 17 heterohelicids and 38 trochospiral forms reveals the identifi cation of 12 major bio-events and allows establishment of three zones based on heterohelicids and fi ve zones based on trochospiral forms. Trochospiral based zones are from the base to the top: 1) Dicarinella primitiva Interval Zone, 2) Dicarinella concavata Interval Zone, 3) Dicarinella asymetrica Total Range Zone, 4) Globotruncanita elevata/Globotruncana arca Concurrent Range Zone, and 5) Globotruncanita ventricosa Interval Zone. The heterohelicid planktonic foraminiferal zones are: 1) Pseudotextularia nuttalli Interval Zone, 2) Sigalia carpatica Interval Zone, and 3) Ventilabrella eggeri/Planoglobuliina manuelensis Concurrent Range Zone. The bioevents and planktonic foraminiferal zones were correlated with previously published works especially on Tunisia and other areas. The lowest occurrence (LO) of Dicarinella asymetrica is the only planktonic foraminiferal datum recorded across the Coniacian/Santonian boundary (CSB). It occurs slightly below the LO of the inoceramid Platyceramus cycloides cycloides representing a good proxy for the CSB. The Santonian/Campanian boundary in the studied sections is characterized by a major faunal turnover represented by the LO of Ventilabrella and Planoglobulina and the LO of Globotruncana and Globotruncanita slightly above. The boundary interval is also characterized by the highest occurrence (HO) of Sigalia, Dicarinella, and Whiteinella.
An upper Campanian to upper Oligocene stratigraphic succession has been examined from six deep exploration wells in the Palmyrides area of Syria. Most of the sedimentary succession contains rich and well to moderately preserved planktonic foraminiferal assemblages that enable successful age determination. The upper Campanian and Maastrichtian planktonic fauna is highly diverse with domination of warm water taxa such as Globotruncana aegyptiaca, Gansserina gansseri, Globotruncanella havanensis, Globotruncanita angulata and Pseudotextularia elegans. The most dramatic turnover occurred across the Cretaceous/Palaeocene boundary when most planktonic foraminiferal species became extinct. The oldest Palaeocene planktonic foraminiferal assemblage, rich in the number of specimens, but not very diverse, includes the following species: Eoglobigerina eobulloides, Globanomalina archeocompressa, Chiloguembelina morsei, Woodringina claytonensis and Parasubbotina pseudobulloides. The late Palaeocene is marked by origination of the morozovellids, acarininids and globanomalinids, while the early Eocene is characterized by a tropical assemblage, dominated by muricate species, and by intensive speciation of Acarinina and Subbotina in the latest part. Most of these species continue into the middle Eocene and become a significant component of the planktonic community. The middle Eocene is characterized by intensive speciation and domination of warm water genera such as Acarinina, Morozovelloides, and to a lesser degree Turborotalia, Globigerinatheka and Hantkenina. The middle/late Eocene boundary is marked by double extinction of the last muricate taxa Acarinina mcgowrani and Morozovelloides crasssatus, which indicate a variable climate, water column instability, and loss of surface habitats. In contrast, Turborotalia and Globigerinateheka become more important in the late Eocene. The Eocene/Oligocene boundary is marked by the extinction of most warm water taxa including Turborotalia cerroazulensis group, Hantkenina, Globigerinatheka and some subbotinids. The beginning of the early Oligocene is indicated by the domination of cool water taxa such as Dentoglobigerina, Globorotaloides, Tenuitella and Chiloguembelina. Speciation of the spinose surface dweller Ciperoella ciperoensis group reflects warming in the late Oligocene. The combined observations of lithology with the diversity and composition of planktonic foraminifera assemblages indicate that the Palmyrides area in Syria was a Tethyan bioprovince with a tropical to subtropical climate from the late Campanian to the end of the Eocene with deposition in deep sea environments (upper bathyal to outer shelf). In contrast, Oligocene deposits and their microfossil content suggest temperate to warm climate conditions and sedimentation in middle to inner shelf environments.
By applying a palynological analysis of the Late Neogene sediments from one exploration well in the area of Eastern Slavonia, three vegetation zones (Z1, Z2, Z3) as conditioned by climate sensitivity were set. On the basis of mutual percentage relations of the occurrence of individual form-species and grouping them according to the results of cluster analysis, these zones reflect the changes of warm-cold and variable humidity periods. The age of zones has been determined: zone Z1 is Pontian, zone Z2 is Pliocene and zone Z3 is Pleistocene-Holocene. In the Pontian, 13 form-species of spores were determined that do not cross the Miocene/Pliocene boundary. In the Pliocene, 4 index form-species of spores were determined that were not found in the Quaternary in the study area. In the youngest sediments of the study area, i.e. Pleistocene and Holocene, 7 index form-species of spores were determined. Together with well logging (gamma ray and specific resistivity logs) of the formation, a model was constructed for the local routine provision of age in the study area. The results are generally consistent with other results obtained from Early Neogene sediments in adjacent areas in the central part of Paratethys, and may serve as a model for the correlation of contemporaneous sediments in other areas of Croatia, e.g. Sava and Drava Depressions , which in effect may contribute to the more efficient investigation of potential hydrocarbon reservoirs.
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