Favorable Areas to Focus Future Trenton Exploration in Indiana

Abstract

Public domain geological and geophysical data has been used to define basement structural features and to determine their influence on Trenton Formation structures and hydrocarbon production in Indiana. The study has identified several favorable areas to focus future exploration efforts.

The crust in Indiana probably formed from the accretion of island arcs to a NE/SW trending continental margin approximately 1.5 bya followed by rifting approximately 1.3 bya. Basement zones of weakness associated with the accretion and subsequent rifting caused much of the structural grain in the region. The crustal extension associated with rifting allowed the emplacement of intrusives, which caused partial melting of the crust and overprinting of the previous structural grain.

Numerous tectonic events along the eastern and southern margins of the craton subsequently reactivated basement structures in Indiana. The most significant events affecting the Paleozoic section were the Taconic and Alleghenian Orogenies.

The relationship between Trenton structure and basement structure is often profound on both regional and local levels. Of particular importance in northern and east central Indiana are basement calderas. In southern and west central Indiana, the interaction between linear faults is important.

Definition of favorable exploration trends can be refined as areas of interest are identified. Detailed potential field data can be used to define leads, minimizing the need for seismic data. In some areas the public domain magnetic data is adequate for this task. Detailed gravity data has been shown to be particularly useful for identifying Trenton structures.

AAPG Datapages/Search and Discovery Article #90258 © 2016 AAPG Eastern Section Meeting, Lexington, Kentucky, September 25-27, 2016