Barrier/Interbed Quantitative Characterization and Modeling in M Block in Orinoco Heavy-Oil Belt

摘要

Block M is located in the eastern part of the Orinoco heavy oil belt.Morichal member is the main oil-bearing layer in this area.It is braided river-delta sedimentary system.The reservoir is mainly composed of medium-fine block sandstones at different stages.It is very thick and it has complex internal structure,so there are some low permeability barriers.The oilfield is developed by horizontal wells,and therefore,the distribution of the Barrier/interbed is an important factor which affects the productivity of a single well and it is the main controlling factor of remaining oil distribution.Based on core observation and physical property analysis,barrier/interbed identification criterions are ascertained using well logs,and there are mainly two types of barrier/interbed,which are muddy barrier/interbed and physical barrier/interbed.Deleveling is the main factor controlling the sedimentation of barrier/interbed.The physical barrier formed the regional barrier together with the muddy barrier,while the interbed is in limited distribution and could be only a local impermeable barrier.Based on above,using the identification results of single well,the spatial distribution of barrier/interbed is characterized controlled by seismic data,which provides geological basis for oilfield development by horizontal well.