Estimation of oil and gas prospects of Western Absheron Oligocene-Miocene sediments based on paleogeology analysis

Oligocene-Miocene sediments are one of the major spread deposits of Azerbaijan. They were deposited in conductive paleotectonical, paleostructural and geochemical conditions. They are widespread and have big thickness. These sediments had a big amount of organic material which turned to hydrocarbons and after the accumulation and migration processes they formed oil and gas fields. Existing in the western part of Absheron peninsula during Oligocene-Miocene period regenerative geochemical conditions are considered favorable for hydrocarbon formation. The analysis of geotectonic development of Western Absheron show that in Oligocene-Miocene and Pliocene-anthropogene periods intensive submergence zones were in the central parts of Baku and Guzdak synclines. Based on the researches it is possible to make a conclusion that during Oligocene-Miocene period in areas of western and northern parts of Absheron peninsula was not favorable conditions for oil and gas deposits formations. Considering with consedimentation development of anticline folds, formation of lithostratigraphic and tectonically screened reservoir is no exception. Reckoning with spread reservoir of Miocene period small area of the western part of Absheron peninsula it is necessary to admit a wide circulation of not anticline types of traps. This can be caused by lithological factor. Traps are formed in clay thickness including sand and siltstone modifications. They are located in cave parts or on wings and slopes of anticline structure. Research works show that in Western Absheron Maykop and Jhokrak and other deposits of Miocene are syngenetic in oil and gas formation. Prospects of oil and gas in Western Absheron are connected with lithological and stratigraphic types of traps which concluded in sand and siltstone layers.