AAPG Bulletin, Vol.96, No.2, 277-300, 2012
Quantification of static connectivity between deep-water channels and stratigraphically adjacent architectural elements using outcrop analogs
This article uses data from well-exposed outcrops and published information to document static connectivity in deepwater channelized systems. Two measures of static reservoir connectivity on outcrop analogs are proposed: margin connectivity and sand-on-sand connectivity. Margin connectivity (C-m) is the length between two stratigraphically adjacent elements not obstructed by a barrier normalized by the total length of the interface. Sand-on-sand connectivity (C-s) is the length of sand-on-sand contacts between two stratigraphically adjacent elements normalized by the total length of the interface. The C-m and C-s are analyzed with regard to four categories: (1) association of architectural elements, (2) stacking pattern of channel elements, (3) setting on the slope-to-basin profile, and (4) net sand content. Results are as follows. First, connectivity varies by association of architectural elements. Channel-lobe contacts have higher C-m and C-s than channel-channel and channel-levee contacts. Second, connectivity varies by stacking pattern of channel elements. Predominantly vertically stacked channel elements have higher C-m and C-s than predominantly laterally stacked channel elements. Also, disorganized nonsequentially stacked channel elements have higher C-m than organized systematically stacked channel elements. Third, connectivity varies by setting on the slope-to-basin profile. Channel elements in confined settings have higher C-m than both weakly confined and unconfined-distributive settings. Fourth, connectivity varies by net sand content. Channel elements with a high net sand content have higher C-m than those with a low net sand content. Therefore, knowledge of a reservoir's placement in these categories can be used to aid in the prediction of static connectivity.