MORRIS, WILLIAM, R.¹ and WILLIAM R. NORMARK^2
1Arco Exploration and Production Technology, Plano, TX
²US Geological Survey

Abstract: Comparing Modern and Ancient Turbidite Channels and Channel-like Elements: Insight for a First Principle Approach to Exploration and Exploitation of Deep-Water Reservoirs

Turbidite elements are basic building blocks for deep-water depositional systems and are recognized from modern and ancient settings using outcrop observations, seismic-reflection profiles, or welllog and core data. Elements can be compared between systems to derive general sedimentologic parameters only if like elements are compared, requiring that their physical scales, shape characteristics, and time scales (duration of activity) are reasonably similar. An understanding of the geometric and sedimentologic characteristics of specific turbidite elements (e.g., channels, where there is an understanding both of their linkage to coeval elements, such as overbank or lobe deposits, and of the associated depositional processes) can allow development of dynamic models specific to each basin. This approach is preferred to forcing data to fit overly simplistic, ad hoc models.

Turbidite-channel elements are a common reservoir target. An understanding of the dimensions, facies, and stratigraphic development of modern and ancient turbidite channels can provide critical data both for exploration and development of resources occurring within channel systems and for distinguishing them from other similarly appearing, laterally-restricted channel-like features such as crevasse-splay channels, megascours and megaflutes. Examples of modern and ancient channels, channel fills, and channel-like features are compared to emphasize the key characteristics of these important turbidite elements. Channels and their fills can exhibit phases of erosion, aggradation or a combination of these histories. Understanding the controls, characteristics and occurrences of these different channel types will allow better prediction of their occurrences and fill types in the subsurface.

AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas