The paper considers probabilistic approach application to assess zonal oil and gas potential of the Visimskaya monocline area. The earlier studies have shown that the processes of generation, migration and accumulation of hydrocarbons (HC) shall be most effectually assessed from a probabilistic standpoint. Generation processes are best described by a complex probabilistic criterion – PcompG
, migration and accumulation processes – by PcompMAC
[1]. These criteria were used to develop a multivariate statistical model – Pcompzon
, acting as an estimate of the system emergence regarding the zonal oil and gas potential. The values were ranked from maximum to minimum to assess the effect of PcompG
and PcompMAC
indicators on Pcompzon
at different ranges of its values. We successively built and analysed 379 models. The analysis of these models has shown that at Pcompzon>0.5 there is a congruent effect of PcompG
and PcompMAC
on this indicator, the effect being different at Pcompzon<0.5. A pattern of its variation over the area was built based on Pcompzon
values, which allowed differentiating the area of the Visimskaya monocline into a high-potential western part and a lower-potential eastern part.