Deep-Water Architectures and Statistics
Greater than 80 BBOE have been discovered in deep-water deposits. These include large discoveries in the Gulf of Mexico, offshore Brazil, North Sea, and offshore Africa that are mostly in young (Neogene) deposits. The play is also relatively immature with most of the discoveries coming in the last 15 years. However, many new prospects are being discovered in both young and in older, more consolidated, and harder to image reservoirs. In both of these settings a knowledge of the depositional setting, architecture, and reservoir statistics are essential guides to better reservoir models. A summary of statistics from over 100 deep water facies outcrops from all types of geographic and basinal settings as well as from sandy or more mud-rich systems were compiled in a database and have been analyzed. Importantly, many of the outcrops contain more than one type of architecture (sheets, channels, thin beds, and mass transport deposits). The association of architectures is important but also the reservoir aspect ratios, N:G, bed lengths (shales and sandstones), and bed thicknesses provide input and constraints on our models. A summary of the reservoir characteristics and statistics are presented for each architectural element, as well as comparative observations between structural setting, lithology and morphometrics.
AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009