Porosity and Permeability in Bioturbated Sediments - Trace Fossils as Indicators of Sedimentary Environments - page 830

FIGURE 12 Burrow-enhanced permeability in surface-constrained textural heterogeneities,
Cusiana-Cupiaugua Field, Llanos Basin (Colombia). Core width is 8.9 cm. Core of the Glossifungites
Ichnofacies at the base of the reservoir sandstone, Eocene Mirador Formation. Under ultraviolet light
(right), it is showing that the burrow systems are filled with hydrocarbons and constitute the primary
pathway for the migration of the oil (photos courtesy of A. Pulham).
Medicine Hat Member can be estimated using the arithmetic mean of the trace-
fossil and matrix permeabilities. This led the authors to suggest that the burrows
are intensely interpenetrating and, at the reservoir scale, fluid flow through the
burrowed intervals is analogous to bedded sandstone.
4.3.3.5 Alderson Member, Lea Park Formation (Cretaceous),
Alberta, Canada
The Alderson Member comprises bioturbated shale, mudstone, siltstone, and
fine-grained sandstone. The gas fields contained within the Alderson Member
produce from continuous and laterally extensive, thin-bedded, fine-grained
sandstone within muddy units at depths < 600 m ( Hovikoski et al., 2008;
Lemiski et al., 2011 ).