Morphology and oil-and-gas content of small amplitude anticlinal structures in the territory of the Mid-Ob oil and gas bearing region (Western Siberia)

The majority of hydrocarbons (oil, gas condensate) in the territory of the Mid Ob Oil and Gas Bearing Region in Western Siberia are attributed to anti-clinal traps. The Mid ObRiver Region is characterized by a high degree of resource prospection and one of the main activities is search and exploration of oiland gas deposits in small amplitude, small size local structures to ensure growth of the reserves. One of the ways to mitigate geological risks in the conduct of geological prospecting work, in a situation involving a depleted stockof large local elevations, is to find out the trends in the structure and location of small amplitude anti-clinal structures.
Materials and methods
To ascertain the nature of productivity depending on the morphology of structures, statistical analysis of the results of prospecting and exploratory drilling was made in respect of structures.
Results
The results of the research undertaken prove that oil and gas content ofthe structures, irrespective of their dimensions in the territory of the Mid Ob Oil and Gas Bearing Region, to a great extent, is driven by the influence of geotectonical factor.
Сonclusions
High productivity of small amplitude structures, especially linear ones, is caused by existence of heightened rock fracturing zones in reservoirs as well as discontinuous faults which create favorable conditions for vertical migration of hydrocarbons. In order to identify and prepare local structures, it is required to carry out detailed seismic exploratory operations next to large geotectonical faults.