About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

AAPG Special Volumes

Abstract


Memoir 103: Critical Assessment of Shale Resource Plays, 2013
Pages 71-80

Chapter 4: Method for Characterizing Source Rock Organofacies Using Bulk Rock Composition

Jonathan C. Evenick, Tony McClain

Abstract

We present a straightforward and effective method to predict source rock organofacies using basic compositional data and a ternary discriminant plot prior to the availability of suitable pyrolysis data. Associating compositional data with organofacies can tie into previously correlated depositional environments and expulsed hydrocarbon types. Using this methodology to preliminarily establish organofacies can help classify source rocks and reduce the practice of comparing source rock plays based solely on production characteristics.

Four basic source rock affinities have been noted: (1) clay-quartz affinity with minor carbonate, (2) clay-quartz affinity with carbonate, (3) carbonate affinity, and (4) bimodal clustering and affinities. Trends in the compositional data can also aid in the prediction of lateral and vertical changes in depositional systems and help ascertain the presence or absence of specific organofacies in an area. Each source rock may have multiple organofacies, and these can vary within or between basins. Ternary plots also distinguish the relative brittleness of lithofacies and, therefore, more suitable unconventional reservoirs. This technique does not directly indicate quality of the source rock; standard geochemical analyses are still needed to identify high-quality source rocks.


Pay-Per-View Purchase Options

The article is available through a document delivery service. Explain these Purchase Options.

Watermarked PDF Document: $14
Open PDF Document: $24