Stratigraphy and Structure of the Arbuckle Limestone in the Arbuckle Anticline: ABSTRACT

Abstract

The Arbuckle limestone of upper Cambrian and lower Ordovician age is 6,700 feet thick and is divided into eight formations which in ascending order are Fort Sill, Royer, Signal Mountain, Butterly (top of Cambrian), McKenzie Hill, Cool Creek, Kindblade, and West Spring Creek. These units crop out over 100 square miles of the Arbuckle anticline in the western Arbuckle Mountains. Principal features of Arbuckle limestone stratigraphy are: 1. The sequence is about 98 per cent carbonate rock, the remaining part being: (a) thin sandstone beds, and (b) shale, chiefly in the form of partings. 2. Limestone is the original deposit and dolomite in general is a replacement of it. The limestone types consist mostly of: (a) algal beds, (b) calcarentite or pellet limestone, grading into intraformational conglomerate, (c) fine-grained limestone, either laminated or massive, and (d) oolitic limestone. 3. Distribution of sand and chert is of value for subdivision and correlation. Sand is lacking in Cambrian strata except coarse arkose at or near the Cambrian-Ordovician boundary, whereas Simpson type sand in limestone is common in Ordovician formations. Chert is rare in Cambrian but prevalent in Ordovician strata. 4. No physical evidence for unconformity is recognized in the Arbuckle limestone. 5. Faunal zones are persistent laterally and are close approximations to true time horizons. 6. Major dolomite-limestone facies are chiefly in Cambrian beds and are regional in scope, the contacts changing progressively along strike at the rate of 5-17 feet per mile. The dolomite-limestone ratio increases eastward. Principal features of structural history are: 1. Anticlinal folding, overturning of the north limb and locally of the south, and accompanying thrust faulting, in post-Hoxbar, upper Pennsylvanian time, coinciding with major folding of the Ardmore basin. 2. Deposition of stratified limestone conglomerate more than 2,000 feet thick in the Turner Falls area, and folding of this conglomerate as part of the Arbuckle orogeny. 3. Later elevation and high-angle faulting, accompanied by only minor folding, in latest Pennsylvanian (Vanoss) time, resulting in deposition of the younger and thinner Pontotoc conglomerate as a bordering rim on the north and west flank of the Arbuckle Mountains. End_of_Article - Last_Page 621------------