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Upper Cretaceous Strata of Kopeh-dagh range, contains divers nannoplankton relative. Abundance and short strarigraphical range of planktonic features and their geographical wide distribution make them as suitable group for biostratigraphical subdivision of Mesozoic and Cenozoic beds and are as effective tools in interregional correlation by attention to the stratigraphical value of calcareous nannoplanktones for age determination of sedimentary beds kalat Formation shales have been studied in three section including Chahchaheh village, Khesht village and Entrance of Kalat city. 47 samples have been collected from these sections and in order to biostratigraphical and paleoecological studies after sampling, processed calcareous nannoplankton studies lead to identification of 14 genera and 28 species, according to these biostratigraphical studies, CC25-CC26 zones of Sissingh zonation for Khesht village and chahchaheh village section and CC25 zone of Sissingh zonation for Entrance of Kalat city are proposed. Base on these biozonation, age of Kalat Formation in Khesht village and chahchaheh village section ranges from late Maastrichtian to latest Maastrichtian and for Entrance of Kalat city section late Maastrichtian is determined. According to paleoecological studies, during deposition of Kalat Formation, Kopeh-dagh basin has been laid between low to medium geographical latitudes and worm climate is proposed for this basin.

The Cephalopod bed (Goniatit horizon) of Shishtu Formation is exposed in the Shotori Range, East of Tabas area. The studied sections were selected in Howz-e-Dorah, Niaz and Hormuk areas. The main Lithology in the Cephalopod bedconsists of red Oolitic limestone, sandy limestone, dark shale and sandstone. Due to it's special morphology and color, this unit is considered as a marker and index bed. In this study, 18 genera and 19 species were identified in which some of the genera is reporting for the first time. These are Warrenella, Spinatrypa, Clieothyridina, Ptychomaletoechia, Megalopterorhynchus, Productella, Tenticospirifer. The studied sections show remarkable changes in diversity, abundance of fossils and thickness of the Cephalopod bed. The lower and upper contact of the Unit can be observed only in Howz-e-Dorah area. Thin section studies of these areas, proves that the sedimentation has occurred in a shallow and high energy environment. According to paleogeography and fauna studies of the Upper Devonian, there are some similarities and relations between the examined sections and the Alborz area. Probably both areas belong to the same common sea at that time of sedimentation. Moreover, in a larger scsle. The similarities among Iran, Kazaghestan, China and most part of Europe moy be indicative of a similar latitude in Upper Devonian time. Taking the age of obtained brachiopods consideration, I suggest Middle Frasnian to Upper Famennian for the age of the Cephalopod bed in this area. It is worth mentioning that the Conodonts (Ashori, 1996) and Cephalopods (Yamini oral Conversation) have given the same age to this bed.

The studies on the paleontoligy and petrography of the northern Birjand sediments in Chahkand region indicates that the beds containing footprints are not flysch type. These sediments composed of three litho and eight sub-lithofacies wich are being explained in the following. The main facies cosist of a) siliciclastic facies including siltstone and sandstone subfacies, b) carbonate lithofacies including micrite and dolomicrite subfacies and c) pyroclastic lithofacies including crystal tuff, calcareious tuff and coarse grain tuff sub facies. The above mentioned main facies have been labed as A, B, and C and the subfacies as A1, A2, A3, B1, B2, C1, C2 and C3 in this research. The studies on the facies reveal that they have been formed in a back arc sedimentary region. The trace fossils of the vertebrates in the region under the investigation belong to pantodonts and dinoceratan wich are two classes of extinct herbivores. Their most famous genera are coryphodonts from order pantodonts, uintatheres and tithanitheres from order dinoceratan wich existed from the end of Paleocene to the end of E ocene. Thus, according to the present investigation the existence of perissodactyles in the region under the study formely suggested by Mirzaie Ataabadi and Sarjeant (2000) is open to doubt.

Both the Oligocene and Miocene sediments in Zagros basin include several formations with considerable lithological changes and fossil diversification. These formations include Pabadeh (Upper Eocene to Oligocene), Asmari, Gachsaran, Razak and Mishan (Guri Member). In order to lithostratigraphic and biostratigraphic studies, has been selected transection along NE to SW of Persian Gulf with 293.6 km in length. There are nine wells along this transection which are from East to west respectively consisting of: Hormuz-D1, Hulur -1, Gavarzin -1, Qeshm -4, Tusan -2, Ashkan 1, Sirri -E2, Sirri F1 and Sirri -D-C1. This transection has been selected based on lithostratigraphic and biostratigraphic viewpoint and boundaries identification. Therefore, 2860 microscopic thin sections were studied. The result of paleontologic studies led to identification of 10 genera and 30 species of planktonic foraminifera as well as 23 genera and 31 species of benthonic foraminifera and biozones separation. Considering the dominant frequency of planktonic foraminifera which is in Pabadeh Formation, biostratigraphy is based on planktonic foraminifera and compared with biozonation of Wynd and Adamz and Bourgeois. Finally according to newest and the most well-known biozonation of foraminifera, 22 biozones have been recognized by studing of thin sections of the wells. The results of this comparison are as follow: 6 biozones were adapted to Wynd, 3 biozones were adapted to Adamz and Bourgeois, 5 biozones were equivalent to Bolli and saunders, 4 biozones were equivalent to laccarino and Premoli Silva, 3 biozones were equivalent to Premoli Silva et al and 1 biozone was equivalent to wade et al. According to the biostratigraphical data and biozonation, the boundaries of Eocene-Oligocene, Oligocene-Miocene and age of deposits were identified. In lithological discution, deposits succession, thickness and distribution of succession, formations sequence and disconformities were identified. Based on the results, biostratigraphy and lithostratigraphy columns were loged. Finally, geography aspect, age and stratigraphic setting of salt have been determined.

In this study, four surface stratigraphy sections such as the foundations of the Bador bahman Kharman kooh,Ab morghan mountain,Asef mountain and one subsurface stratigraphy section called Sarvestan oil well (Iranian National Oil Company) related to Jahrom and Asmari formation have been selected. The total thickness of the sediments in these sections is 1517 meters. The shady areas are located in the interior Fars and based on litology leyering each sections is divided to the Lower, Middle, and Upper parts in the surface stratigraphy section Sadee hieman, Lower boundary of Axma ity with Jarom Semation and its Upper boundary is consistent with Racak. Lithologically, Jahrom formation and Aymari formation are divided into three parts, Jahrom formation age is Late Palnocene to Middle Focene and Asmari formation is Early Oligocene (Ruppelinn) to Early Miocene (Burdigalian) age .In the surface stratigraphic section of Kharman kooh, Jahrom formation is lithology divided to one part. The age of this section is considered of Middle Eocene. Lower boundary of Asmani formation is inconsistent unconformity with Jahrom formation and its Upper boundary is consistent with Razak. Besed on index foraminifera in this section, Asmani Formation age is of the Early Oligocene (Ruppelian) to Early Miocene (Burdigalian). In this section, Asmari fermation is lithologically divided into three parts. In the surface stratigraphic section of Ab morghan mountain, the Lower boundary of Jahrum formation is consistent with Sachun formation and the Upper boundary of Jahrum formation with Asmari formation is unconformity inconsistent, in this section the Upper boundary of Asmari formation with Razak formation is characterized with the marl layers. Based on the index Foraminifers in this section, the Jahrom formation age is the Late Paleocene to Middle Eocene and age of the Asmar formation is Oligocene (Ruppelian-Aquitanian). Jahrom formation is lithologically divided to three parts and the Asmari formation in this section is lithologically divided into two parts. In the surface stratigraphic section of Asef mountain, the Lower boundary of Jahrum Formation is consistent with Saohun formation and the Upper boundary of Jahrum formation is inconsistent unconformity with Asmari formation. Based on the index foraminifera, Jahrom formation age is Early Eocene to Middle Eocene, Jahrom Formation in Asef mountain is lithologically divided into three parts. In the subsurface stratigraphic section of Sarvestan, based on index foraminifers the age of the Jahrom formation is Middle Eocene to Upper Eocene and Asmari formation age is Ruppelian to Aquitanian. Jahrum formation into Srvestan, is lithologically divided into two parts and the age of this section is Late Eocene. Asmari formation in Sarvestan is lithologically divided into three parts and the age of this section is Aquitanian. According to the index foraminifera identified in the stratigraphic sections studied six biozones are related to Jahrum formation with the age of Late Paleocene to Late Eocene and eight biozones are related to the Asmari formation with the age of Ruppelian to Burdigalian. Also, the biostratigraphically review of Jahrom and Asmari formations boundary condition in the study stratigraphic sections showed that in the majority of sections, incisions have disconformity and it can be considered equivalent to the Pyrenean orogenic phase performance.

What is the present thesis is questionable. Brachiopods of A member Gachal formation in 70km of Southwestern of Tabas in Kalmard central zone (was of Kalmard fault). A member Gahal formation in the studied area have 82 thickness. And lithology mainsly include: Linestone, Linestone with inter bed of shale and small quantity quartzarenite and sandstone. This member is repose above of upper Devonian sedimentions of Rahdar formation and is covered by B member Gachal formation which is dolomitized. Totally 22 Genera and 28 brachiopod species have been introduced, which all for onset is reported from area. Introduced Brachiopods have relation with Alborz lower Carboniferous Brachiopoda funna. This is indicate which these areas has covered by common sea in the lower Carboniferous. This assemblage have similarities whith Brachiopod of other world such as France. Belgium, England, Kazaghestan and China. Therefor can say which mentioned areas with Similarity Brachiopnda fauna was settled in similar latitude. To object of study of microfacies and sedimentary invironment, is samplied from studied area. In the course of study microfacies thin sections, is distinguished two king of carboniferous and terrigenus facies.

Relative abundance and short stratigraphical rang of nannofossils has caused these fossils to be the most suitable group for biostratigraphical subdivitions of mesozoic and cenozoic beds. Planktonic feature and as the result thier geographical wide distribution are effective in the inter-regional correlation, By attention to the stratigraphical value of calcareous Nanrioplanktons for age determination of sedimentary beds Abderaz formation in Taherabad section was studied. This Formation crops out in Taherabad synclinal situated 80km North of Mashhad Taherabade-Turk village. With geographical coordinats of 60°,30.56°E and 30,37,30°N The formation conformably overlay placed to Aitamire formation. Lithologically the formation contains dark grey and olivaceaus calcareous marly, grey calcareous shales and grey chalky limestone. 24 samples were collected and shifted to the laboratory where they prepared in both ways (smear slides and centrifuging) and their nannofossils contents were studied and photographed by LM and SEM, 17 Family 42 genera and 83 species were determined. Three biozan erected, they coincide with CC14 to CC16 of Sissingh (1977). So age of this formation in Taherabad section is suggested late coniacian – santonian.

The current project investigates the sediment of Triassic system, determines the biozones of Conodonts, the quality of upper and lower boundaries and the studies of Lithostratigraphy in Til-Abad section(Northern Shahrood) Elikah Formation in Til-Abad includes 6 stone units including the lower and middle Triassic and a unit at the top which is actually the upper Triassic(the base of Shemshak Group), The lower boundary of Elikah Formation begins with a discontinuity of disconformity type in this section after a Dolomite and Limestone unit and finally a Bauxite Laterite horizon which indicates the period of water discharge and tropical weather conditions. After that, some traces of Claraia and Calcaire vermicular was seen on the Elikah base in the thin bedded limestones. At the end of first stone unit of this section, some traces of storm-bel was observed. Finally, the upper boundary of Elikah Formation faced a discontinuity of disconformity type by a unit of Coal bearing shale with Shemshak Group, In the conducted investigation on Triassic deposits in Til-Abad section, 67 stone samples were taken out of 325 meters, and 16 conodont species were pick out. Conodont elements were found only in 15 stone samples. Generally, from 250 Conodont elements and 16 species of Conodont, four biozones were identified which are as the following: 1) Hindeodus parvies Taxon range zone 2) Isarcicella isarcica Taxon range zone 3) Pachycladina longispinosa - Pachycladina symmetrica Assemblage zone 4) Hadrodontina anceps Taxon range zone In addition, these components were identified in this section: Hindeodus sp., Hindeodus parvus erectus, Hindeodus parvus, Hindeodus postparvus Hindeodus cristulus, Ellisonia sp. Pachycladina sp., Pachycladina symmetrica Pachycladina longispinosa, Hadrodontina sp., Hadrodontina anceps Parachirognathus ethingtoni, Lonchodina sp. Hindeodella sp., Cypriella mediocris Elikah Formation in Til-Abad section is the same age as Scythian - Anisian and includes six stone units. The existing Conodont elements in this study have CAI-4 which potentially go into last stage of dry gas production and lack hydro-carbon

Acid leaching method used for processing 48 geological on sample on a section in Mighan area (Eastern Alborz). The final result the age of this section is from M.Devonian-Early carbonifeorous. Collected fossils: Ostracods, bivalves, gasteropods, brachiopods, briozoa, Crinoids, Scolocodonts, Microvertebrate remains, tooth fish, Scales of fish and extracted from this section fifty species/sub species related to conodont were identified. Tuwnty-eight species/sub species related to tooth fish, scales of fish were identified as: Apatognathus spp, indet, clydagnathus ormistoni, lcriodus aff, iowaensis iowaensis, lcriodus alternathus alternathus, Icriodos sp. A, Icriodos sp. B, Icriodos sp.C, Icriodos sp.D. Palmatolepis triangularis, Palmatolepis sp., Polygnathus aequalis, Polygnathus evidens, Polygnathus sp.A, Polygnathus sp.B. Polygnathus sp.C. Polygnathus sp.D. Polygnathus sp., Polygnathus communis commnonis, Polygnathus ratebi, Polygnothus brevilaminus, Polygnathus capollocki, Polygnathus aff, mirficus, Scaphignathus velifer velifer, Polygnathus Semicostatus, Polygnathus nodocostatus, Polygnathus communis collinsoni, Polygnathus delicatulus, polygnathus cf. semicostatus, following zone can be Stubles, this section is assignable to? Givetian-Frasnian-Farmenian (older than transitans zone, transitans to linguiformis zones, triangularis to crepida zones, rhomboidea to postera zones, expansa to praesulcata zones.) There are significant Fossils in some limestone beds, for example at the base of the section remains of trilobite (Ncocalmonia (Bradocryphaeus) sharudensis) is present. Cephalopodes (Gomphoceras.sp) also can be collected with this trilobite in the base of section. Aboundant corals were collected from base of section. Near the upper part of the section several classdexrelated to: brachiopods, trilobites (phacops.sp), vertebrates, cephalopods and conolaridae are present. The D/C boundary in Mighan area can be corrleted to the Marakib section in the Morroco.

Cretaceous deposits in different part of Iran are not the same, because of the forming time condition. Therefore litologic units of upper cretaceous have not named officially and have got local names, except of Zagros and Kopedagh. In order to considering upper cretaceous deposit in the north of Alborz a section has chosen around Pole-Zoghad area at 21" Km. of the south of Chaloos. This section appears as a trench in the freeway of Marzan Abad-Chaloos with the geographic coordinates of 36° 31' N and 51° 20° E. Upper cretaceous deposits in this section has got 1585 m. thickness and it contains limestone, marL limestone and coverage of volcanic stones that placed on 3 m. siltstone that settled on the basaltic primes that are consider as Chaloos formation. The upper boundary of this section is covered by plants and it is not visible where it is finished. 51 samples were gathered from this section that 39 samples were used to study foraminifera and 12 samples (30 slides) were used for palynologic studies. According to inquires that had been doing on foraminifers in thin sections and also isolate foraminifers 43 species and 17 genus of foraminiferas were recognized and according to foraminifera studies 7 biozone were determined in late Coniacian-Masstrichtian age. Defining biozones are: 1. Hedbergella holmdelensia - Dicarinella concavara Interval Zone (Late Coniacian) 2. Dicarinella asymetryca Total Range Zone (Santonian) 3: Globotruncanita elevata Total Range Zone (Early Campanian) 4: Globotrimcanita calcarata Interval Zone (Middle Campanian-Late Campanian) 5: Globotruncanita calcarata-Gansserina ganssert Interval Zone (Early Maastrichtian) 6. Gansserina gansseri Total Range Zone (Late Maastrichtian) 7: Abathomphalus mayaroensis Total Range Zone (Late Maastrichtian) Also 78 species and 69 genus of dinoflagellate and some spore and pollens and algal pieces and algal spore and acritare have identified by using palynologic slides. In order to vertical expand of dinoflagellet in this section 3 palynozone have recognized that confirmed data of Toraminifera age. Defining palynozone are: 1- Isabelidinium cooksoniae-Ellipsodiniun rugoluvum Zone (Santonian) 2- Alisogimnium euclaense-Triblastida utinensis Zone (Maastrichtian) 3- Palaeoperidinium pyrophorum Zone (Campanian) For studying palynomorphs and the determining sedimentary environment the Tison Triple Diagram had used and then 4 palynological facies were determined. They are II, IV, VI, VIII. The environment was studied according to these facies it was a shallow into basin that gradually became deeper, the environment further the seashore was semi-oxide to non-oxide and finally deepness reduced and marginal basin became semi-oxide to non-oxide again. By using of palinological factors, organic protect factors and the factors that are resulted of foraminifera in the paleocology analysis it was defined that the basin was without oxygen to semi-oxide condition with slow rhythm of sedimentation existence of algal spores and pieces of alga confirm warm and humid climate in the late cretaceous. According to ecological studying and facies that had been recognized by palynomorphs and bentic and pelagic feraminifera the late cretaceous has had various of deepness in this area.