NEW GEOLOGIC MAPPING IN THE TULSA METRO AREA, NORTHEAST OKLAHOMA

The first round of detailed mapping of the Tulsa Metro Area, with the completion of the Claremore and Sageeyah 7.5’ Quadrangles, highlights a number of subtle lithologic and structural characteristics overlooked in previous studies of these areas, as well as providing a better understanding of the overall stratigraphic framework of the Desmoinesian section in northeast Oklahoma.

Of the lithologic changes, there are extensive Quaternary terrace deposits along the Verdigris River that were previously unreported in the Sageeyah Quad. There are also new occurrences of the Bluejacket Sandstone Member, an important subsurface marker horizon, and the underlying Savanna Formation in the Claremore Quad.

Structually, there are several broad anticlines and synclines that trend roughly northwest-southeast. These folds are best found by careful attention to outcrop pattern and noting subtle changes in bedding dip and dip direction in relation to contour of key marker horizons. Subsurface correlation of wire-line logs provides independent verification that these structures are present. Several northeast-southwest trending faults also occur. These faults appear to be normal, have displacements ranging from 15 to 50 feet, and the extension of fracture zones related to one fault may have locally influenced the course of the Verdigris River.

Some discrepancies in the overall Desmoinesian section are present. Currently, several small-scale maps of this area have erroneously place the Boggy-Senora contact at the base of the Chelsea Sandstone, at the Tiawah Limestone, or at the top of the Upper Taft Sandstone; however, in order to conform more closely to regional stratigraphic precedence, this contact was moved down to the base of the Weir-Pittsburg coal. Further up the Desmoinesian section, some reports have placed the Sageeyah Limestone at the base of the Oologah Limestone instead of at the top of the Labette Shale. Field characteristics of the Sageeyah Limestone consisting of textural, bedding, and color differences, coupled with a sharp, irregular upper contact suggestive of an unconformity, implies it is depositionally unrelated to the overlying Oologah Limestone.