TAXONOMICAL CONSIDERATIONS, PHYLOGENY, PALEOGEOGRAPHY AND PALEOCLIMATOLOGY OF THE MIDDLE EOCENE (BARTONIAN) PLANKTIC FORAMINIFERA FROM JABAL HAFIT, AL AIN AREA, UNITED ARAB EMIRATES

The taxonomical consideration, probable phylogeny and stratigraphic significance of twenty-eight middle Eocene (Bartonian) planktic foraminiferal species from the eastern limb of Jabal Hafit, Al Ain area, United Arab Emirates (UAE), Northern Oman Mountains (NOM) are presented, and twenty one of them are illustrated. Identification of these twenty-eight species belonging to ten genera Globoturborotalia, Subbotina, Globigerinatheka, Inordinatosphaera, Orbulinoides, Hantkenina, Acarinina, Morozovelloides, Pseudohastigerina and Turborotalia has led to the recognition of three biostratigraphic zones, in ascending order: Morozovelloides lehneri PRZ (E11), Orbulinoides beckmanni TRZ (E12) and Morozovelloides crassata HOZ (E13). Eight out of the identified species are recorded, in this study, for the first time from Jabal Hafit: Globoturborotalia martini, Subbotina gortanii, S. jacksonensis, S. senni, Globigerinatheca barri, Acarinina praetopilensis, A. punctocarinata and Morozovelloides bandyi. The second or third record of three species from J. Hafit outside its original records are recently documented by the present author: Inordinatosphaera indica, Hantkenina australis and H. compressa. The paleontology, paleoclimatology and paleogeographic distribution of the identified taxa at Jabal Hafit and other Paleogene outcrops in the UAE and Tethys are presented and discussed. The identified fauna emphasis the wide geographic areas in the Tethys, from Atlantic to Indian-Pacific Oceans via Mediterranean.

The Maastrichtian-Paleogene rocks in the United Arab Emirates (UAE) crop out as a discontinuous mountains belt (jabals) and hills (qarns) around the western front of the North Oman Mountains (NOM) and Jabal Hafit is one of these mountains (Lat. 24˚ 06ʹ and24˚ 09ʹ N, Long. 55˚ 46ʹ and55˚ 49ʹ E) and has a NNW-SSE asymmetrical double plunging anticline ( Figure 1). Many studies over nearly three decades have been carried out on Al Ain area (Jabal Hafit, J. Malaqet and J. Mundassa). The great abundance and wide distribution of planktonic foraminifera in marine sediments and their rapid evolution during middle Eocene time make them a powerful biostratigraphic tool for global biostratigraphy and precise regional and interregional correlation.

GEOLOGICAL SETTING
The Maastrichtian-Oligocene post-nape sediments crop out around the eastern part of the UAE at NOM. These mountains were formed in response to two main orogenic events. The regional hiatuses in the pelagic succession are also ascribed to the tectonic events, as the Late Cretaceous is a time of great tectonic activity in this critical area of Tethys, and the Eustatic sea-level changes may have had a secondary effect on the area. The first one resulted from the late Cretaceous (Coniacian-Maastrichtian) obduction of the Semail Ophiolite and associated sedimentary and volcanic rocks (Sumeini, Hawasna and Haybi groups), onto the eastern margin of the Arabian Platform. The second event reactivated in early Eocene and later times of Miocene and it is correlated to the Zagaros Orogeny in Iran (Ricateau and Riche, 1980;Searle et al., 1983). It was responsible for the formation of foreland folds and thrust faults and folding of Maastrichtian-Paleogene neoautochthonous units in the foredeep along the western front of the Oman Mountains (Glennie et al., 1974;Searle et al., 1983;Nolan et al., 1990;Warrak, 1996).
The Hafit structure formed after the Miocene as a result of the second late Paleogene deformation event, while noted that this structure is interpreted to be post-middle Eocene in age, and was the response to the collision of the Arabian-Eurasian Plates which began during the late Eocene and continues to the present day (Noweir, 2000;Zaineldeen and Fowler, 2003). Anan noted that the eastern limb of J. Hafit anticline exposes a nearly vertical dipping middle-upper Eocene succession along the Al Ain-Mazyad asphalted road (Anan, 2005). This succession is equivalent to the mappable rock unit, coded Tle4 (where T=Tertiary, l=lower, e= Eocene), or Ain Al Faydah Member of the Dammam Formation (Hunting Geology and Geophysics Limited, 1979;Hamdan and Bahr, 1992;Krumbein, 1942).

STRATIGRAPHY OF THE STUDY AREA
The eastern limb of J. Hafit anticline, east of Al Ain-Mazyad asphalted road, consists mainly of an alternated marl, nummulitic marly limestone and hard limestone beds, but some gypsiferous shale beds are found. One sample of the latter gypsiferous shales (sample no. 15, bed no. 4, about 15 m thick, Figure 2

Subbotina jacksonensis (Bandy, 1949) (Fig. 3.4) 1949 Globigerina rotundata jacksonensis
Remarks: This middle-late Eocene species probably evolved from early Eocene-early Oligocene Subbotina eocaena by developing more embracing chambers and a reduced ultimate chamber that projects over the umbilicus . It is recorded here, for the first time, from the middle Eocene of J. Hafit, UAE. Remarks: Many authors considered this species as a basic stock from which all Eocene Globigerina groups or lineages have been differentiated (Stainforth et al., 1957;Haggag and Luterbacher, 1991). It was originally described from the middle Eocene of New Zealand, and later from the early-middle Eocene in many parts of the Tethys: Pakistan, India, Libya, Egypt, Indian Ocean, UAE, Qatar, India, southern Indian Ocean and Iran (Haque, 1956;Samanta, 1970;Barr and Brggren, 1980;Youssef et al., 1983;Premoli Silva and Spezzaferri, 1990;Cherif et al., 1992;Beckmann, 1953;Mukhopadhyay, 2003;Vahdatirad et al., 2016). Remarks: This early-middle Eocene species has slightly embracing chambers of the last whorl and nearly closed umbilicus. Blow considered Subbotina senni as a possible ancestor of the genus Globigerinatheca (Blow, 1979). According to Toumarkine & Luterbacher, the value of it lies in its resistance to solution in very deep water (Toumarkine and Luterbacher, 1985). It is recorded here, for the first time, from the middle Eocene of J. Hafit, UAE.
Globigerinatheca subconglobata (Shutskaya, 1958 Remarks: This species is characterized by its evolute outline, four chambers in the last whorl, crown-like flatter final chamber not enveloping or covering previous one. A group researcher, fig. 6) figured this species gave rise to G. subconglobata curryi (Haggag and Luterbacher, 1991). In other study they has been noted that the early members of Globigerinatheca (G. subconglobata) appear for the first time in its nominate biozone E8 (Anan et al., 1992). A group scientist considered it an ancestral to all the other globigerinathekid lineage or groups in E9 (Premoli Silva et al., 2006). My specimen is here considered very similar, if not identical, to the lectotype of G. subconglobata. Remarks: Bolli noted that this species is the last Globigerinathekid to disappear in the late middle Eocene (Bolli, 1972). Haggag & Luterbacher (fig. 6) figured this species to be evolved from the middle Eocene G. i. index and gave rise to late middle Eocene G. index tropicalis (Haggag and Luterbacher, 1991).
Remarks: This species was originally recorded from India documented in Loeblich & Tappan ( Loeblich and Tappan, 1988;Mohan and Soodan, 1967 ; Mohan and Soodan, 1 ). It was also recorded and illustrated outside India, for the first time, from the Bartonian Orbulinoides beckmanni Zone from sample 15 of J. Hafit (UAE) (Anan, 2017). It is characterized by its spherical-subspherical test and irregular elongate meandriform bullae. A group researchers considered Inordinatosphaera indica as a problematic genus and species, unknown, possibly a highly unusual new form, while Loeblich & Tappan treated it as formal taxa in the Globigerinidae family, which is accepted in this study Loeblich and Tappan, 1988).

PALEOGEOGRAPHY AND EUSTATIC SEA LEVEL
The paleogeographic distribution in some countries in the Tethyan province ( Fig. 3): North America (USA, Mexico), Europe (Spain, France, Italy), North Africa (Tunisia, Libya, Egypt), West Africa (Tanzania), East Africa (Gulf of Guinea), West Asia (Qatar, UAE, Iran), Southern Asia (Pakistan, India). Based on that faunal distribution, the following remarks can be presented: 1. The Paleogene paleogeographic maps (partly or regionally), used by many authors, i. e.: show that the Tethyan Realm had been connected with the Indo-Pacific Ocean from the east to the Atlantic Ocean to the west (Berggren, 1978;Moore et al., 1978;Adam et al., 1983).

Haq & Aubry
added that the North Africa and Middle East firmed important parts of the Tethyan link between the Atlantic and the Pacific Oceans during the Early Cenozoic (Haq and Aubry, 1980). 3. Anan concluded that the Tethyan Realm during the middle-late Eocene extends to the southeast and connected with the Indo-Pacific Realm via seaway separating Arabia from Iran-India region (Anan, 1995).
5. Rögl noted that between the stable Eurasian Platform and the relics of the Tethys elongate deep basins had formed and north of India a marine connection stretched to the west Pacific (Rog, 1999). The western end of the relic Tethys connected the Indo-Pacific and Atlantic Oceans.
6. Meulenkamp and Sissingh noted that the Arabian Platform still largely covered by the sea in the early-middle Eocene times and was subject to a major regression in middle-late Eocene (Meulenkamp and Sissingh, 2003).
7. Anan suggested that the unconformity at the boundary between the Ain Al Faydah and Mazyad Members is associated with the major sealevel lowering (about 41 Ma), within T. rohri Zone (P14) (Anan, 2005). The global marked fall in the eustatic sea level took place at the end of the middle Eocene (~ 40 Ma) and J. Hafit.
2. To the west of UAE, 29 species were recorded from the Bartonian in Egypt by Haggag & Luterbacher [ 31 ] including two new Egyptian species Turborotalia nukhulensis and T. sinaiensis by the same authors. Only 8 species were recorded from Tunisia (Ben Ismail-Lattrache, 2000).
4. To the east of UAE, 11 species were recorded from India and Indian Ocean, but only 9 species from east of Japan at Pacific Ocean (Mohan and Soodan, 1970;Krasheninnikov and Hoskins, 1973).
5. The variation of foraminiferal numbers mostly related to different factors (depth, water temperature, water-column stability, salinity, dissolved oxygen, light penetration, etc.) between these vast localities.

PALEOCLIMATOLOGY
1. Gohrbandt recorded abundant, diverse, and typically tropical planktonic foraminifera assemblages in his study of Austria, indicating deposition in a relatively deep marine environment with connection to the open-sea, while the northern site of the sequence with nummulitic limestone suggesting shallower conditions (Gohrbandt, 1967).
2. Cherif & Boukhary noted that the synthesis of stratigraphical data on uppermost Lutetian and lowermost Bartonian exposures in Egypt enables to suggest the occurrence of a regional epeirogenic tectonic movement before the end of the Lutetian (Cherif and Boukhary, 1978). The general influx of clastic sediments noticed in most Bartonian exposures in northeastern Egypt suggests that a marked change of climates was probably arid, Bartonian climates rather wet.
3. Keller noted that general cooling trend between middle Eocene to early late Oligocene is indicated by the successive replacement of warm middle Eocene surface water planktic species by cooler late Eocene intermediate water species (Keller, 1983).

Cherif & El
Deeb noted that arid climate at the close of the middle Eocene became markedly wetter and seems to have been accompanied by a cooling of water temperature (Cherif and El-Deeb, 1984). Moreover, the climatic changes inferred from J. Hafit area seems to have been widespread, at least in part of the Middle East.
5. Anan noted that in the middle-late Eocene time, the UAE and surrounding area had been located in the tropical and warmtemperate region based on many faunal environmental elements such as the presence of keels, accessory apertures and tubular spines in some middle-late Eocene planktic foraminiferal assemblage (Anan, 1995).
6. Norris noted that the reproductive mechanisms and behavior must therefore play key roles in speciation rather than geographic barriers to dispersal (Norris, 2000).

7.
A group researcher noted that the evolution of Hantkenina (with tubular spines) occurred during the initial rapid phase of Cenozoic cooling (around early-middle Eocene boundary), which followed the extremely warm climate optimum of the early Eocene (Coxall et al., 2003).

8.
A group researcher noted that related species within genera tend to have similar isotopic characteristics, indicating that most speciation occurs without major changing in habitat (Pearson et al., 2004).
In this study, the middle Eocene (Bartonian) horizon at the eastern limb of J, Hafit in general has been located in the tropical and warm-temperate region based on many faunal environmental elements: presence of keel (Morozovelloides lehneri), accessory apertures (Acarinina rohri, A. topilensis, Globigerinatheka subconglobata and Orbulinoides beckmanni), tubular spines (Hantkenina alabamensis), but shallower conditions in rich Nummulitids horizons, particularly in the top of the study section. This conclusion is in accordance with Frerichs who noted that the presence of keels, accessory apertures, and tubular spines of some of planktic foraminiferal species suggests a tropical-subtropical sea (Frerichs, 1971).

SUMMARY AND CONCLUSIONS
Bartonian planktonic foraminiferal assemblages of the Dammam Formation in the eastern limb of Jabal Hafit, Al Ain area, UAE, have been analyzed in detail and the following conclusions have been presented: 1. Twenty-eight planktonic foraminiferal species belonging to ten genera have yielded three biozones. They are, in ascending order: Morozovelloides lehneri PRZ (E11), Orbulinoides beckmanni TRZ (E12) and Morozovelloides crassata HOZ (E13).
2. The middle Eocene in the eastern limb J. Hafit yields 28 planktic foraminiferal species in this study, compared with 21, but only 9 species for the same stratigraphic succession (Anan et al., 1992;Cherif et al., 1992).
6. The second or third record of three species from J. Hafit outside its original records are recently documented by the present author: Inordinatosphaera indica, Hantkenina australis and H. compressa (Anan, 2017;Anan, 2018).
7. The middle Eocene (Bartonian) horizon at the eastern limb of J, Hafit in general has been located in the tropical and warm-temperate region based on many faunal environmental elements: presence of keel (Morozovelloides lehneri), accessory apertures (Acarinina rohri, A. topilensis, Globigerinatheka subconglobata and Orbulinoides beckmanni), tubular spines (Hantkenina alabamensis), but shallower conditions in rich Nummulitids horizons, particularly in the top of the study section. This conclusion is in accordance who noted that the presence of keels, accessory apertures, and tubular spines of some of planktic foraminiferal species suggests a tropical-subtropical sea (Frerichs, 1971).

The intraformational conglomeratic bed (ends the Ain Al Faydah
Member) at the end of the Tle4 (bed no. 13, Fig. 2), suggests a minimal reworking and accumulating in low-energy environment in a short distance of transportation on a slight steepening paleoslope from the positive localized source area during the time of active tectonic (Fig. 4).

ACKNOWLEDGEMENT
I would like to express my thanks to Prof. Hanspeter Luterbacher, Tübingen University, Germany for kind help in photography of the fauna through Prof. Mona Haggag, Ain Shams University, Egypt and for her kindly review the illustrated species. The anonymous reviewers helped to improve the manuscript are greatly acknowledged. I also indebted to my daughter Dr. Huda H. Anan for her kind help in preparing the figures and plates.