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 This research for introduce and paleontology of Early Cretaceous Rudist in the Middle Tethys Ocean, stratigraphic section of the kalleh pahnoo has been selected from the Shahkouh Formation in Central Iran (Khor and Biabank region). The studied section consists of 120 m thin layer to massive limestone. Studies on 106 specimens collected and prepared from this section have led to the identification of specimens from the Hippuritoid class. Overall, 2 genera and 5 species of Radiolitidae family and 1genera and1 species from Requienidae family were identified. According to studies age of Kalle pahnoo deposits, late Aptean-Albian was suggested. Paleoecology studies on growth form and shapes of rudist communities indicate relatively warm environment with low salinity in this region. elevated rudists' morphology revealed a relatively calm and quiet environment, with continuous deposition.

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In this resaerch for introduction of late Cretaceous calcareous nannofossils in Middle Tethys Ocean, Azizabad stratigraphic section of the the Farokhi Formation in Central Iran has been selected. Thickness of formation in this section is 233 meters and consists of marl and marly limestone. In this research 42 species belong to 25 genera of nannofossils with good preservation were identified. Based on the index nannofossilspecies and nannofossil assemblages, CC21-CC26 for Farokhi Formation determined. Deterrmined biozones indicate early late Campanian – late late Maastrichtian age for Farokhi Formation in Azizabad section.

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Ophiolite complexes are interpreted as remnants of oceanic lithosphere that have emplacement along the edges of continents after an oceanic basin close. Iranian ophiolites, considered as remnants of closure of the Tethys (or Neo-Tethys) Ocean and its branches. These ophiolites are outcrop in two distinct regions: 1) Ophiolites coeval with the Zagros orogenic belt, and 2) Ophiolitic assemblages surrounding the Central Iranian Microcontinent. The comparison of these two ophiolite complexes indicates noticeable differences between them. Therefore, in order to understanding the tectonic sitting of their formation, initially, the geological, petrological, geochemical features, and the age of these rock units were examined and compared. Subsequently, to delineate the boundary between the two mentioned ophiolite complexes, field surveys were conducted, and geological maps of the region were prepared.Based on results, the ophiolite complexes surrounding the Central Iranian Microcontinent include the Sabzevar ophiolites in the north, the Neyriz-Dehshir-Baft ophiolites in the west, the Kahnuj ophiolites in the southwest, the Makran ophiolites in the south, and the Turbat Heydariyeh - Tchehel-Kureh ophiolitic belt in the east demonstrate similar features and it seems they have formed in a same tectonic environment. They exhibit fundamental differences from the Zagros ophiolites and have formed at different geological time, too. The ophiolites around the Central Iranian Microcontinent mark remnants of oceanic lithosphere that formed as a result of the opening of a rift basin between two continental blocks and its expansion into an intracontinental oceanic basin that known as a branch of Tethyan Ocean. This Ring Ocean existed during late Mesozoic, and as a result of its closure, these ophiolite complexes were formed