Current Abstract

November 13th, 2025 Meeting Abstract

“Fractures and Drainage Mechanisms: North Midway Sunset Diatomite“

Presented by: 

Hanaga Simabrata and Adam Cox, Berry Corporation

Abstract: 

Fractures are important conduits in diatomite reservoirs, given their low matrix permeability (< 5 mD). This study integrates multiple datasets (e.g., pre- and post-steam cores, image logs, and comparisons between original wells and sidetracks/infills) to elucidate the relationship between fractures and depletion mechanisms. The results indicate that the primary fractures in diatomite reservoirs are oriented parallel to bedding and are likely critically stressed, accompanied by secondary fracture sets oriented orthogonal to bedding. Consequently, the main depletion pathway in the Opal-A phase follows bedding planes, resulting in thin bed-bounded depletion bands along completions. In contrast, within the deeper diatomite transition zone (Opal-A/CT phase), depletion bands are considerably thicker, suggesting the presence of larger, bedding-orthogonal, throughgoing fractures that connect multiple pay intervals. As a result, transition zones tend to exhibit higher early recovery factors despite their limited areal extent.

Biography: