About This Item

Share This Item

The AAPG/Datapages Combined Publications Database

Dallas Geological Society


Petroleum Geology of the Fort Worth Basin and Bend Arch Area, 1982
Pages 157-177

Stratigraphy of the Barnett Shale (Mississippian) and Associated Reefs in the Northern Fort Worth Basin

James D. Henry


The Barnett Shale originated as a normal marine shelf deposit on the southwestern flank of the subsiding Southern Oklahoma aulacogen, probably due to the Middle or Late Mississippian collision of the North American plate with South America and/or North Africa. It is a hard, bituminous formation that is easily distinguished in drill cuttings or on electrical and porosity logs. Subsurface correlations allow the Barnett to be informally subdivided into four or five members which can be traced through most of Jack, Wise, and Montague counties. It unconformably overlies rocks of Early to Middle Ordovician age, and it is in turn — with a few local exceptions — conformably overlain by the shales and limestones of the Marble Falls Formation.

The growth of Mississippian pinnacle reefs was initiated with the inundation of North-Central Texas by the warm, shallow Barnett seas. The reef complexes are subdivisible into three constituent facies: the reef core, the reef flanks, and the interreef area. The reef cores are porous enough to serve as stratigraphic traps for oil and gas, and they have yielded excellent production in the northern part of the Fort Worth basin for several decades. The Barnett Shale, though itself unproductive, is believed to be the hydrocarbon source for the reef production.

Pay-Per-View Purchase Options

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

Protected Document: $10
Internal PDF Document: $14
Open PDF Document: $24