Globotruncanella Havanensis Research Articles

ХАРАКТЕРИСТИКА ВІДСЛОНЕНИХ РОЗРІЗІВ ТУРОНУ-МААСТРИХТУ ПЕНІНСЬКОЇ ЗОНИ УКРАЇНСЬКИХ КАРПАТ ЗА ДРІБНИМИ ФОРАМІНІФЕРАМИ

Purpose. Micropaleontological characteristics of individual exposed sections of Turonian-Maastrichtian sediments of the Pieniny Klippen Belt in the Ukrainian Carpathians with detailed age determination by foraminifera. Method. Field geological and stratigraphic research, foraminiferal analysis. Results. In the studied sections, Turonian, Coniacian, Campanian and Maastrichtian deposits were identified. The deposits of the Lower Turonian are determined by the disappearance of the genus Rotalipora and the appearance of the species Dicarinella hagni; the Upper Turonian was identified by the distribution of representatives of the genus Marginotruncana. According to the division of the Upper Cretaceous of the Ukrainian Carpathians after planktonic foraminifera, the Dicarinella concavata Zone (top of the Turonian-most of the Coniacian) and the sequence of zones in the Campanian-lower Maastrichtian interval were identified: Globotruncanita elevate Zone; Contusotruncana morozovae Zone, Globotruncanita stuarti Zone. The established subdivisions are correlated with the biochronozones of the modern Geologic Time Scale such as Dicarinella concavata Zone (top of the Turonian – most of the Coniacian), Globotruncanita elevate Zone, Contusotruncana plummerae Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Gansserina gansseri Zone within the Campanian-lowermost Maastrichtian. Scientific novelty. For the first time, exposed sections of the Turonian-Maastrichtian of the Pieniny Klippen Belt of the Ukrainian Carpathians were studied and correlated with modern regional and international foraminiferal scales for the appearance of index species. Practical significance. The results obtained are important for the compilation of regional stratigraphic schemes and interregional correlation of sediments.

Biostratigraphy of the Late Cretaceous-Early Paleocene Succession in Selected Wells, Jambur Oil field, Kirkuk, Northern Iraq

The Late Cretaceous-Early Paleocene Shiranish and Aliji formations have been studied in three selected wells in Jambur Oil Field (Ja-50, Ja-53, and Ja-67) in Kirkuk, Northeastern Iraq. This study included lithostratigraphy and biostratigraphy. The Late Campanian-Maastrichtian Shiranish Formation consist mainly of thin marly and chalky limestone beds overlain by thin marl beds, with some beds of marly limestone representing an outer shelf basinal environment, the unconformable contact with the above Middle Paleocene-Early Eocene Aliji Formation contain layers of limestone with marly limestone and chalky limestone which represents an outer shelf basinal environment. Five Biozones in the Shiranish Formation were determined which are: 1.Globotruncanita calcarata Range Zone (part). 2.Globotruncanella havanensis Partial Range Zone. 3.Globotruncana aegyptiaca Interval Zone. 4.Gansserina gansseri Interval Zone (Part). 5.Abathomphalus mayaroensis Range Zone. While in Aliji Formation there were two biozones determined which are: 1.Guembelitria Cretacea Partial-Range Zone. 2.Parvularugoglobigerina eugubina Total-Range Zone.

Planktonic foraminiferal biostratigraphy and determination of the Santonian-Campanian boundary in the Zagros sedimentary basin, SW Iran

The carbonate-dominated Upper Cretaceous Ilam Formation is representative of an important reservoir in the Zagros Basin. In this study, planktonic foraminiferal biostratigraphy of the Ilam Formation was investigated in the Kuh-e-Surgah section in western Iran. In the studied section, the 170 m thick Ilam Formation is mainly composed of imestones with shale intercalations. The formation conformably overlies and underlies the Surgah and Gurpi formations, respectively. Twelve genera and 24 species of planktonic foraminifera were identified. The following planktonic foraminiferal biozones were identified: the Dicarinella asymetrica Total Range Zone (latest Coniacian- late Santonian), the Globotruncanita elevata Partial Range Zone (Santonian to early Campanian), the Globotruncana ventricosa Interval Zone (middle to late Campanian.), the Radotruncana calcarata Total Range Zone (late Campanian.), the Globotruncanella havanensis Partial Range Zone (late Campanian) and the Globotruncana aegyptiaca Interval Zone (late to latest Campanian). In general, the biozones show that the Ilam Formation in the studied section is latest Coniacian-late Campanian in age. The Santonian-Campanian boundary in the Kuh-e-Surgah section correlates with the Globotruncanita elevata Partial Range Zone. The recognized biozones in the Ilam Formation are comparable with those recorded in other parts of the Tethyan Realm. The crinoid species Marsupites testudinarius is absent in the studied section. Generally, the last occurrence of this cosmopolitan species indicates the base of the Campanian stage. The Santonian/Campanian boundary was placed in the lower part of the Globotruncanita elevata Partial Range Zone at the base of the Ilam Formation in the studied section.

Planktonic foraminiferal distribution of the Late Cretaceous to late Paleocene deposits of the Bandar Abbas area (Zagros Belt, SW Iran): An update of the bio- and lithostratigraphic framework

In this paper, we present a biostratigraphic study of the planktonic foraminiferal associations of the Gurpi Formation outcropping in the Bandar Abbas area of the Zagros Belt (SW Iran). Two stratigraphic sections, Kuh-e Khush and Kuh-e Khamir, were logged and sampled, and the identification of the planktonic foraminiferal assemblages has allowed the recognition of eight Cretaceous biozones, namely Dicarinella asymetrica Zone, Globotruncanita elevata-Globotruncana ventricosa Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Radotruncana calcarata–Globotruncana aegyptiaca Zone, Globotruncana aegyptiaca-Gansserina gansseri Zone, Gansserina gansseri Zone and Contusotruncana contusa-Abathomphalus mayaroensis Zone. This planktonic foraminiferal zonal framework reveals a latest Coniacian to late Maastrichtian age for the deposits of the Gurpi Formation in the two studied sections. The Cenozoic Interval of the studied sections, represented by the Pabdeh Formation, is attributed to the P3–P6a integrated Zone in the Khush section and the P4c Subzone (Acarinina soldadoensis) in the Khamir section. The data show that the Gurpi Formation at the Khamir locality rests disconformably upon the shallow neritic facies of the Ilam Formation, while in the Khush section this formation disconformably overlies the shallow carbonates of the Sarvak Formation. In addition to the in situ biota, reworked microfossils, such as calpionellids, calcareous algae and benthic foraminifera from older Jurassic (Surmeh Formation) and Cretaceous formations (Surgah equivalent, Sarvak, Kazhdumi and Dariyan formations) are recorded within several stratigraphic levels of the Gurpi Formation.

Late Campanian-Maastrichtian foraminiferal biostratigraphy and paleoecology at Wadi Tarfa (North Eastern Desert, Egypt)

The upper Campanian-Maastrichtian (from Globotruncanella havanensis to Plummerita hantkeninoides zones) foraminiferal assemblages at the Wadi Tarfa section in the Egyptian North Eastern Desert are studied to infer paleoenvironments and relative sea-level changes. The multivariate R-mode hierarchical clustering and the Q-mode Nonmetric Multi-Dimensional Scaling (NMDS) of the benthic foraminiferal dataset have been attempted to quantify the vertical variations in paleobathymetry, oxygenation, and trophic conditions. The inferred foraminiferal-based sea-level curve reveals paleodepth fluctuations ranging from middle neritic to upper bathyal and distinguishes five 3rd order sequences, two in the upper Campanian and three in the Maastrichtian. The development of the inferred relative sea-level curve expresses greater control of the eustasy. Also, the regional impact of the Syrian Arc Orogeny (SAO) subordinately led to amalgamation and repositioning of some sea-level events. The lowermost part (Gl. havanensis Zone) was deposited under stressed, low oxygenated, weakly eutrophic bottom-water conditions. However, well‑oxygenated oligotrophic conditions occurred around the level of the Campanian/Maastrichtian (C/M) boundary, as inferred from the predominance of heavily calcified epibenthic oxic species. We attributed this oligotrophy to the oceanic circulation change and the accompanying climatic cooling experienced at that time. The remainder of the early Maastrichtian through late Maastrichtian experienced an environmental shift toward mesotrophic conditions without considerable oxygenation change. The latest Maastrichtian, however, reveals low-oxic mesotrophic-weakly eutrophic bottom-water conditions, which is likely owed to the Deccan volcanism induced food detritus enrichment.

Biozonation and paleobathymetry of the Gurpi Formation in the Dasht-e Arjan section , Zagros area , based on foraminifera

In this research the Gurpi Formation in the Zagros Basin outcropping in the Dasht-e Arjan section, Shiraz province ,for the purpose of biozonational and Paleobathymetric studies were investigated. The thickness of these sediments is about 130 m and consists of Limestones and Shales.To determine the palaeobathymetry of the Gurpi Formation, Planktonic and benthic foraminifera were investigated . A depth of about 270m to 510m was determined for these sediments based on the ratio of planktonic foraminifera to the total assemblages of foraminifera after omitting infaunal benthic foraminifera (%P*) by using the equation D = e (3.58718+(0.03534 × %P* )).In this study sixty-two species of planktonic foraminifera belonging to eighteen genera were recognised .According to the studied planktonic foraminifera the Upper Cretaceous deposits in this area were divided into nine biozones as following :biozone1- Dicarinella concavata Interval Zone. Biozone2- Dicarinella asymetrica Total Range Zone. Biozone3- Globotruncanita elevata Partial range zone .Biozone4- Globotruncana ventricosa Interval Zone. Biozone5- Radotruncana calcarata Interval zone. Biozone 6- Globotruncanella havanensis Partial Range Zone. Biozone7- Globotruncana aegyptiaca Interval Zone. Biozone 8- Gansserina gansseri Interval Zone. Biozone 9- Contusotruncana contusa Interval Zone Based on the studied planktonic foraminifera the Early Santonian to Maastrichtian ages were determined for the sediments .

Biostratigraphy of planktonic foraminifera in the Abtalkh Formation and determination of the Santonian/Campanian Boundary in the Kopeh-Dagh Sedimentary Basin

ABSTRACT:We studied the Abtalkh Formation from five outcrops (Sheikh, Hajgelichkhan, Qarehso, Muzduran, and Deraz-Ab) in the Kopeh-Dagh sedimentary basin. A total of 30 species of planktonic foraminifera belonging to 21 genera were recorded. These species were used to subdivide the Abtalkh Formation into seven biozones (Dicarinella asymetrica Zone, Globotruncanita elevata Zone, Contusotruncana plummerae Zone, Radotruncana calcarata Zone, Globotruncanella havanensis Zone, Globotruncana aegyptiaca Zone, and Gansserina gansseri Zone). The Abtalkh Formation was deposited during the late Santonian-latest Campanian and the Santonian-Campanian boundary is identified based on the last occurrence of Dicarinella asymetrica. The base of the Campanian stage was delineated by the extinction of the marginotruncanid group, the first occurrences of Pseudotextularia nuttalli and Rugoglobigerina rugosa, and on the last occurrence of Dicarinella asymetrica.

Planktonic foraminiferal biostratigraphy and lithology of the Upper Cretaceous (upper Campanian-Maastrichtian) and Palaeogene succession of the Palmyrides (Syria)

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.

Upper Cretaceous planktonic foraminiferal biostratigraphy of the Zagros Basin (West Iran) with reference to sea-level changes

In this study, an Upper Cretaceous sedimentary sequence in the Anaran Anticline (located in the central Zagros) is investigated to assess planktonic foraminiferal biozonations and implications for sea level changes. The thickness of this sequence is about 215 m, characterized by shales and limestones with thin marly limestone intercalations. In total, 51 species and 22 genera of planktonic foraminifera in 12 biozones spanning the middle Campanian to late Danian ages were delineated in the studied sequence. Additionally, planktonic foraminiferal morphological models, species abundance percentages, and the planktonic/benthonic foraminiferal ratio (P/B) ratios were assessed to reconstruct changes in sea level. The statistical studies on the different genera and species and the P/B ratio from the base to the top of the sequence indicate sea level transgressions during the middle Campanian and Maastrichtian in the Contusotruncana plummerae Interval Zone, Radotruncana calcarata Total Range Zone, Globotruncanella havanensis Partial Range Zone, Globotruncana aegyptiaca Interval Zone, Contusotruncana contusa Interval Zone, and part of the Abathomphalus mayaroensis Interval Zone.Moreover, species belonging to the deep-water morphotype (G. arca, G. hilli, G. linneiana, and G. ventricosa) are mostly present. Furthermore, two intervals of this sequence are associated with falling sea levels: 1) at the Campanian/Maastrichtian boundary in the middle of the Gansserina gansseri biozone; 2) from the late Maastrichtian close to the Cretaceous/Paleogene boundary with marly lithology.

Planktonic Foraminifera Biostratigraphy of Shiranish Formation in Piramagroon Anticline, NE Iraq

67 planktonic foraminiferal species were identified from the Shiranish Formation. On the basis of the stratigraphic distribution of the planktonic foraminiferal assemblages recognited of six biozones within the Shiranish Formation representing an age ranging from Middle Campanian – Early Maastrichtian, these zones are from older at base: 6 -Planoglobulina acervulinoides Interval Zone. 5 - Contusotruncana contusa Total Range Zone. 4 -Gansserina gansseri Interval Zone. 3 - Globotruncana aegyptiaca Interval Biozone. 2 -Globotruncanella havanensis Interval Biozone. 1 -Globotruncana ventricosa Interval Biozone

Calcareous nannofossils and other proxies define the Santonian–Campanian boundary in the Central Crimean Mountains (Alan-Kyr section)

The taxonomic composition and detailed stratigraphic distribution of the calcareous nannofossils from the Santonian and Campanian of the Crimea have been studied for the first time. The identified assemblage of calcareous nannofossils in the Alan-Kyr section consists of 85 species, including all primary and additional zonal markers. The following calcareous nannofossil zones and subzones have been recognised and correlated with planktonic (PF) and benthic (BF) foraminifera zones: transitional Santonian–Campanian CC17 or latest Santonian UC13 (Dicarinella asymetrica/D. concavata PFZone and the lower part of Globotruncanita elevata/stuartiformis PFZone), lower Campanian CC18a/UC14a, CC18b–c and CC19/UC14b–UC15a (Globotruncanita elevata/stuartiformis PFZone), lower Campanian CC20/UC15b (Contusotruncana plummerae/Globotruncana ventricosa PFZone), upper Campanian CC21/UC15c (Contusotruncana plummerae/Globotruncana ventricosa PFZone and Globotruncanella havanensis PFZone) and upper Campanian CC22/UC15d (Globotruncanella havanensis PFZone). Using magnetostratigraphic data as the primary source for definition of the base of the Campanian, we place the Santonian–Campanian boundary in the Alan-Kyr section at the level of the base of Chron C33r and inside the nannofossil transitional Santonian–Campanian CC17 or lower Campanian UC14 Zone and the planktonic foraminifera Santonian D. asymetrica/D. concavata Zone. This conclusion is supported by the relative position of other microfossil bioevents: the first occurrence of Broinsonia parca parca, which happens just above the highest occurrences of both Dicarinella asymetrica and D. concavata, as well as the lowest occurrence of the benthic foraminifera Neoflabellina asema.

Depositional environment, sequence stratigraphy and biostratigraphy of the Gurpi formation in Fars zone, Zagros Basin (SW Iran)

To study the Gurpi Formation deposits in Fars area, 230 thin-sections which belong to Well No. 43 have been studied. The Gurpi Formation is 155 m in thickness. Lithology of the Gurpi Formation is mainly composed of thin to medium limestone, argillaceous limestone and shale. Lower boundary of the Gurpi Formation with the Ilam Formation is continuous and its upper boundary with the Pabdeh Formation is disconformity. In biostratigraphy analysis, 14 species belonging to 31 genera of planktonic and benthic foraminifers were identified, and 6 biozones were recognized based on planktonic foraminifera as follow: (1) Globotruncanita elevata Partial range Zone, (2) Globotruncana ventricosa Interval Zone, (3) Radotruncana calcarata Total range Zone, (4) Globotruncanella havanensis Partial range Zone, (5) Globotruncana aegyptiaca Interval range Zone, (6) Gansserina gansseri Interval range Zone. Based on the fossil contents and the identified biozones, the relative age of the Gurpi Formation is Early Campanian–Maastrichtian. Petrographic studies of the Gurpi Formation led to recognition of six facies including five carbonate facies and one shale facies. All facies of the Gurpi Formation belong to the open marine environment, which are deposited in a shelf model. Based on facies analysis and sea level curves, three depositional sequences along with four sequence boundaries due to discontinuities and relative levels of sea level falling were identified. The sequence boundaries at the lower boundary and in the middle part of the Gurpi Formation are type II sequence boundary (SB2). Only the upper boundary of depositional sequence 3 (the boundary between the Gurpi and Pabdeh formations) due to exposure and presence of erosion effects is revealed as a type I sequence boundary (SB1).

Earliest Campanian - latest Maastrichtian sequence stratigraphy based on planktonic foraminifera, Fars province, Zagros, Iran

The Gurpi, Tarbur and Sachun formations have been investigated in the studied section in the Fars Province, in order to determine their sequence stratigraphy. On the basis of done studies on the cores of borehole, four main microfacies have been recognized in four stratigraphic sequence deposited during the Campanian to Maastrichtian. The lowermost sequence, was deposited in the early Campanian-early late Campanian which include wackestone to packestone texture with Globotruncanita elevata Zoneand Globotruncana ventricosa Zonethatrepresentative of the deep marine and outer ramp. The intermediate and uppermost sequences (sequences two, three and four) display well developed deposits formed in the end of the Campanian (Radotruncana calcarata Zoneand Globotruncanella havanensis Zone), formed during the Maastrichtian (Globotruncana aegyptiaca Zoneand Gansserina gansseri Zone) and the end of the Maastrichtian (Omphalocyclus macroporus - loftusia sp assemblage Zone) on pelagic, hemipelagic, outer and middle ramp. On the basis of the sequence stratigraphic chart, the transgression of the upper Cretaceous sea started since the early Campanian and continued gradually until the early Maastrichtian. Then, until the end of Maastrichtian, the area has been emerged. The sequence stratigraphic architecture of Campanian/ Maastrichtian Gurpi, Tarbur and Sachun formations model is in a good agreement with global sea level changes.

Timing of depositional regime changes during the Late Cretaceous evolution of the Southern Pontides (Ankara, Central Anatolia, Turkey)

During the Cretaceous, vast amounts of marine sediments were deposited along the south-facing active margin of the Eurasia. A stratigraphic section of 91 m was analyzed for planktonic foraminifera (75 samples), with the aim of establishing a refined biostratigraphy of Cenomanian–Campanian deposits in Central Anatolia. A biostratigraphic framework comprising nine biozones was established. In ascending order, the Rotalipora cushmani, Whiteinella archaeocretacea and Helvetoglobotruncana helvetica zones were defined in the uppermost Cenomanian–Turonian interval. The lack of Coniacian index markers suggests the existence of a hiatus for this interval. In the upper part of the section, the Dicarinella asymetrica, Globotruncanita elevata, Contusotruncana plummerae, Globotruncanella havanensis and Globotruncana aegyptiaca zones were identified for the Santonian and Campanian deposits. The presence of Gansserina gansseri, Globotruncanita angulata, G. conica and G. pettersi in the uppermost part of the section shows that the section ends at the base of the Gansserina gansseri Zone, indicating uppermost Campanian. The planktonic foraminifera biozonation framework provides strong evidence for the timing of the depositional history of the active continental margin that developed south of the Pontides. These phases are mainly the formation of olistostromes of pre-Santonian age, following condensed carbonate deposition during the Santonian and finally the switch from forearc deposition to the formation of a thick sequence of siliciclastic succession starting in the Campanian.

Biostratigraphy of Upper Cretaceous planktonic foraminifera of the Abtalkh Formation in an east-west transect, Kopet-Dagh Basin, northeastern Iran

The Upper Cretaceous Abtalkh Formation of the Kopet-Dagh Basin (northeastern Iran) was studied in four stratigraphic sections (Bahadorkhan, Hammam Galeh, Type section and Shorab). All sections display limestones, shales and calcareous shales. The Bahadorkhan section is approximately 480 m thick. We identified 32 planktonic foraminifera species belonging to 13 genera in 6 biozones: 1. Dicarinella asymetrica Total Range Zone, 2. Globotruncanita elevata Partial Range Zone, 3. Contusotruncana plummerae Interval Zone, 4. Radotruncana calcarata Total Range Zone, 5. Globotruncanella havanensis Partial Range Zone and Globotruncana aegyptiaca Interval Zone. Based on foraminiferal biostratigraphy, the Bahadorkhan section was dated to the latest Santonian to late Campanian. This study identifies 11 genera and 25 species of planktonic foraminifera in the 1500m thick Hammam Galeh section, spanning 7 biozones: 1. Dicarinella asymetrica Total Range Zone, 2. Globotruncanita elevata Partial Range Zone, 3. Contusotruncana plummerae Interval Zone, 4. Radotruncana calcarata Total Range Zone, 5. Globotruncanella havanensis Partial Range Zone, 6. Globotruncana aegyptiaca Interval Zone, 7. Gansserina gansseri Interval Zone. Latest Santonian to late Campanian ages have been established for the Abtalkh Formation. The type locality of the Abtalkh Formation is 750mthick and contains 31 planktonic foraminiferal species belonging to 12 genera. Based on this fossil content, we identified 6 biozones. The age of the formation is estimated to be the latest Santonian to late Campanian, as for the Bahadorkhan type section. The Shorab section of the Abtalkh Formation is 990m thick. In this section, 19 species belonging to 10 genera were identified, as were 5 biozones: 1. Globotruncanita elevata Partial Range Zone, 2. Contusotruncana plummerae Interval Zone, 3. Radotruncana calcarata Total Range Zone, 4. Globotruncanella havanensis Partial Range Zone, 5. Globotruncana aegyptiaca Interval Zone. Based on this fossil assemblage, the Shorab section dates to the early to late Campanian.

Foraminiferal biostratigraphy of Upper Cretaceous (Campanian – Maastrichtian) sequences in the Peri-Tethys basin; Moghan area, NW Iran

The Upper Cretaceous sediments in the Moghan area, NW Iran, contain diverse planktonic and benthic foraminifera, with a total of 33 genera and 53 species (17 genera and 38 species of planktonic foraminifera and 16 genera and 15 species from benthic foraminifera), which led to the identification of six biozones spanning the middle Campanian to late Maastrichtian. A detailed paleontological study and biostratigraphic zonation of these sequences has been carried out in four surface sections. This study shows that there are two different facies in the Moghan area, based on the faunal content. A deep open marine condition exists in the Molok, Selenchai and Nasirkandi sections. In these sections, Upper Cretaceous sequences have diverse planktonic foraminiferal species including the Globotruncana ventricosa (middle to late Campanian), Globotruncanella havanensis (late Campanian), Globotruncana aegyptiaca (latest Campanian), Gansserina gansseri (latest Campanian to early Maastrichtian), Contusotruncana contusa- Racemiguembelina fructicosa (early to late Maastrichtian) and Abathomphalus mayaroensis (late Maastrichtian) zones. This deep open marine setting grades laterally into shallower marine condition dominated by large benthic foraminifera such as Orbitoides media, Orbitoides gruenbachensis, Orbitoides cf. apiculata, Lepidorbitoides minor, Pseudosiderolites sp., Siderolites praecalcitrapoides, Siderolites aff. calcitrapoides and Siderolites calcitrapoides. This facies is mainly recorded in the Hovay section. A detailed biostratigraphic zonation scheme is presented for the studied sections and correlated with the results of other studies in the Tethyan realm. This is the first biozonation scheme for Upper Cretaceous sequences of the Moghan area that can be used as a basis for ongoing studies in this area and other parts of Tethys basin.

Biostratigraphy and Sequence Stratigraphy of Campanian and Maastrichtian Succession, Qutbabad Well, Zagros (Iran)

The Qutbabad section of the Gurpi, Tarbur and Sachun Formations in the Fars Province (Zagros Basin) has been studied, in order to determinate its microfacies and sequence stratigraphy. On the basis of thin section studies of cores from Qutbabad Well in the Gurpi, Tarbur and Sachun Formations of the Zagros Basin, four main microfacies have been recognized within four stratigraphic sequences deposited during the Campanian to Maastrichtian. Depth and sea level changes were the main controls on the distribution of these microfacies. The microfacies are: Pelagic; Hemi-Pelagic; Outer ramp; and Middle ramp. The lowermost sequence was deposited in the Early Campanian-early Late Campanian and includes wackestone to packestone textures with biozones Globotruncanita elevate and Globotruncana ventricosa representative of the Pelagic, Hemipelagic and Outer (ramp/shelf). The intermediate and uppermost sequences (sequence two, three and four) display well developed deposits formed at the end of the Campanian (Radotruncana calcarata zone and Globotruncanella havanensis zone), beginning of the Maastrichtian (Globotruncana aegyptiaca zone and Gansserina gansseri zone) and the end of the Maastrichtian (Omphalocyclus macroporus - loftusia sp assemblage zone) on the Pelagic, Hemipelagic, Outer and Middle ramp. On the basis of the sequence stratigraphic chart, the transgression of the Upper Cretaceous Sea started from the Early Campanian and continued gradually towards the Early Maastrichtian. Then, until the end of Maastrichtian, has had regression. This resulted that the sequence stratigraphic model of the Campanian- Maastrichtian Gurpi, Tarbur and Sachun Formations has architecture similar to those that have developed from global sea level changes.

Biostratigraphy of the Gurpi Formation (Santonian–Maastrictian) by using Globotruncanidae, Zagros Mountains, Iran

The study of Globotruncanids of the Gurpi Formation at Sepidar anticline in Zagros Mountains led to distinguishing Santonian to Late Maastrichtian biozones. Eight biozones were determined: biozone I (Dicarinella asymmetrica Zone) belongs to Santonian. Biozone II (Globotruncanita elevata Zone), biozone III (Globotruncana ventricosa Zone), biozone IV (Radotruncana calcarata Zone), biozone V (Globotruncana stuarti Zone) and biozone VI (Globotruncanella havanensis Zone) are of the Early to Late Campanian. Biozone VII (Gansserina gansseri Zone) and VIII (Contusotruncana contusa Zone) suggest the latest Campanian to Late Maastrichtian.

Late Cretaceous/Early Paleocene Biostratigraphy of the Northern Portion of the Bornu Basin, Nigeria

Ditch cutting samples from Kasade-1 well were processed for microfauna, nannofossil and palynomorphs to throw more light on biostratigraphic events in the northern portion of the Bornu Basin, Nigeria. The lower section of the well within interval 990 - 1565 m yielded fairly abundant foraminifera species, while the upper section was barren. Palynomorph distribution follows the same pattern as observed for foraminifera except that few fresh-water algal species, Botryococcus braunii, were recovered from the upper section. The samples are devoid of nannofossil but contain few ostracod species, echinoid remains and fish tooth. Recognition of two planktonic foraminifera zones, Globotruncanella havanensis and Globotruncana aegyptiaca, enabled the delineation of the Campano-Maastrichtian and Maastrichtian boundary. The Cretaceous Tertiary boundary was inferred based on the top occurrence of palynomorph Dinogymnium euclaense. An abrupt truncation in the distribution of foraminifera species at a depth of about 990 m suggests unconformity, a widely reported event that followed the Santonian squeeze in the entire mega-Chad Basin.

Stratigraphic correlation of the Late Cretaceous Simsima Formation United Arab Emirates and Akveren Formation, northwest Turkey

Latest Cretaceous (Campanian-Maastrichtian) microfossils are used to correlate the carbonate rocks of the Simsima Formation in the northeastern part of the Arabian Peninsula (Northern Oman Mountains, United Arab Emirates and Oman) with the Akveren Formation in Kandira (northwest Turkey, near Black Sea region). Both formations have characteristically rich planktonic foraminiferal and calcareous nannofossil faunal assemblages that permit the recognition of the Globotruncanella havanensis Zone and Quadrum sissinghii Zone CC22. The palaeontological data is used to build an appropriate palaeoenvironmental model for the latest Cretaceous Aruma Group in the Oman Mountains foreland basin. The study reveals that the Late Cretaceous formations of UAE and Turkey can be divided into an open marine carbonate shelf facies (planktonic foraminifera/calcareous nannofossil biomicrite) and a shallow-marine carbonate facies (rudistids, coralline algal foraminiferal biomicrite).