Diorite Sill

McALESTER TEXARKANA- Diorite, light-greenish-gray, medium- to fine-grained, quartz-free, with much andesine plagioclase and ferromagnesian minerals altered to chlorite and limonite; occurs in sections 10 and 15, Township 5 South, Range 23 East, in Womble Formation, striking North, 45 degrees East and dipping 10 degrees to 20 degrees Northwest; thickness, 2 to 10 feet. Occurs in POTATO HILLS, BROKEN BOW UPLIFT or ADJACENT SMALLER UPLIFTS IN SOUTHEASTERN PART OF OUACHITA MOUNTAINS.
State Oklahoma
Name Diorite Sill
Geologic age Late Ordovician ?
Lithologic constituents
Igneous > Plutonic > Dioritic > Diorite (Dike or sill)

Heran, W.D., Green, G. and Stoeser, D.B., 2003, A Digital Geologic Map Database of Oklahoma: USGS Open File Report 03-247, scale 1:250,000.


Marcher, M.V. and Bergman, D.L., 1983, Reconnaissance of the water resources of the McAlester and Texarkana quadrangles, southeastern Oklahoma: Oklahoma Geological Survey, Hydrologic Atlas 9, scale 1:250,000, 4 sheets. (Geology on sheet 1 compiled by M.V. Marcher and D.L. Bergman, in 1971 and revised by R.O. Fay, in 1978.)

Cederstrand, J.R., 1996h, Digital geologic map of McAlester-Texarkana quadrangles, southeastern Oklahoma: U.S. Geological Survey Open-File Report 96-377, (3 diskettes), URL address is: http://ok.water.usgs.gov/gis/geology


NGMDB product
Counties McCurtain