Simultaneous attribute visualization to define connectivity between reservoirs
José Ricardo B. da Silva, Yuri Fieschi L. C. G. Bezerra, Rogério Santos · 2015
Definition of reservoir connectivity using conventional 3D seismic data is an old and hard challenge for geoscientists when characterizing properties associated to permeabilities, isolated production blocks and drainage of hydrocarbons. To help on this characterization, many seismic attributes have been used by the industry trying to establish a consistent link between seismic properties and different behaviors of reservoirs. One difficult on overcoming the interpretation of many attributes at “same time” is the way to visualize them according to some geologic sense for any method. In Teal South field, GOM, Pennington et al (2001) show that time-lapse seismic observations have revealed that one undrilled reservoir (Reservoir B) near a producing reservoir (Reservoir A) was exhibiting time-lapse changes consistent with expansion of a free gas phase, with oil being lost trough the spill point. They conclude that both reservoirs were communicated and they both were suffering a regional pressure decline across faults. In the same area, Ezawi et al (2012) studying the connectivity of the same reservoirs using Instantaneous Amplitude have concluded that the declined pressure was due the escape of hydrocarbons to one of the neighboring reservoirs (Reservoir B) with the intrusion of water from the base of the producing reservoir (Reservoir A). Here in this paper, about the same area of Teal South Field, 4D seismic data were used, one Base (year of 1995) and a Monitor (Phase 1- year of 1997), to understand the possible ways that water could go between the reservoirs A and B. For such an understanding was applied a simultaneously visualization of inverted seismic data and geometric attributes post-stack. The results show new possibilities of connectivity between Reservoir A and B and the advantage of using simultaneous display of different seismic attributes, to provide spatial perspectives of interpretation of reservoir characteristics and possible connectivity, identified by 3D seismic data.