Geologic Map of the Witter Quadrangle, Madison County, Arkansas DGM-AR-00926 Geology by Richard S
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Arkansas Geological Survey Digital Geologic Quadrangle Map Bekki White, Director and State Geologist Witter Quadrangle, Arkansas Geologic Map of the Witter Quadrangle, Madison County, Arkansas DGM-AR-00926 Geology by Richard S. Hutto and Garrett A. Hatzell 2018 7256 III SE (HARTWELL) UNITED STATES DEPARTMENT OF THE INTERIOR WITTER QUADRANGLE ARKANSAS GEOLOGICAL SURVEY 7256 II SE Trace Creek Shale - dark gray to black shale, locally 7.5 MINUTE SERIES (TOPOGRAPHIC) o 7256 II SW Ùat 93 45' 4 000m HUNTSVILLE 7 MI. (KINGSTON) Correlation of Map Units interbedded with thin- to medium-bedded claystone, siltstone, Stratigraphic Column 33 E 434 4 4 o A 35 36 42'30" 2.7 MI. TO ARK. 74 o S (HUNTSVILLE) R 26 W 4 4 36 00' R 25 W 40' 40 1 510 000 FEET 42 443 93 37'30" and sandstone. Sandstone is very fine to coarse grained. o 36 00' Locally, near the base, a 20- to 25-foot (6- to 7-meter)-thick, Ùat Ùbd 610 000 thin- to thick-bedded or massive, friable sandstone unit is FEET Holocene & present. Unconformable with the underlying Kessler Limestone Qat Qls Quaternary SystemSeries Member Formation Pleistocene of the Bloyd Formation. Ranges from 80 to 240 feet (24 to 73 900 Unconformity meters) thick. Ùa o5 Ùa Bloyd Formation (Lower Pennsylvanian, Morrowan) - o o Atokan composed of shale, sandstone, and limestone units divided o Ù at Ù 250 3 o 3 at into several Members. From youngest to oldest they are: 5 800 3983000m N 3 3983 Kessler Limestone, Dye Shale, Parthenon sandstone, and Ùbp 3 o Unconformity Brentwood Limestone. In the Bloyd type area at Bloyd Mountain, 20 miles (32 kilometers) west in Washington Ùbd 6 County, the Woolsey Shale is present between the Brentwood Q Qat Limestone and Dye Shale. Here, this interval is occupied by ls o o Ù Qls bp the Parthenon sandstone. On the Witter quadrangle, the 700 Pennsylvanian Ùhc Parthenon sandstone is a prominent bluff-former along War 4 Unconformity Eagle Creek. Ranges from 140 to 180 feet (43 to 55 meters) Qls 200 thick. Ùbb Morrowan Ùat Kessler Limestone - sandy, fossiliferous, commonly Ùa Ù 39 bd oncolitic limestone. Light gray on fresh surfaces, weathers 82 Ù 3982 600 at Ùhp dark gray. Fossils include: crinoids, tabulate and rugose orals, Atoka brachiopods, trilobites, bryozoans, and shark teeth. Sandy Unconformity intervals are commonly cross bedded. Locally contains coal Atokan Ù 6 hp o Ùhc fragments, phosphatic pebbles, and conglomeratic beds. Because this unit is so thin, it is mapped with the Dye Shale. Qls Ùat Unconformity Areas where the Kessler crops out extensively in stream 500 150 Ùbp beds are marked with a black, stippled pattern. Ùbb Mp Chesterian Mississippian Conformable with the underlying Dye Shale. Ranges from 5 to 15 feet (1.5 to 5 meters) thick. Greenland 3981 3981 Dye Shale - mostly gray to black shale. Locally contains ironstone concretions. Locally interbedded with thin- to 5 400 o Ùbp medium-bedded sandstone and siltstone. Conformable with the underlying Parthenon sandstone. Ranges from 40 to 100 Ùbd Ùa Ozark Plateaus feet (12 to 30 meters) thick. Trace Creek Mp Parthenon sandstone - thin- to massive-bedded, very fine- 100 Ù bd Ùbp to coarse-grained, micaceous sandstone. Tan on fresh 300 surfaces, weathers tan to brown. Commonly exhibits tabular Ùhc Springfield Salem cross-bedding. Commonly contains white quartz granules and 4 Ùa Ùhp pebbles. Unconformable with the underlying Brentwood Kessler o Limestone. Ranges from 10 to 40 feet (3 to 12 meters) thick. 3980 o 3980 Brentwood Limestone - thin- to thick-bedded, Dye 200 Pennsylvanian 4 Ùbb fossiliferous limestone, locally interbedded with sandy 3 o Bloyd Boston Mountains limestone, dark-gray to black shale, and light-gray siltstone. 50 Parthenon 7 Limestone is light gray on fresh surfaces and weathers light o o o gray to white. Locally exhibits cross-bedding. Locally contains Ùhc Brentwood 57' 30" Qat Ùhp Witter quadrangle phosphatic pebbles and abundant invertebrate fossils, 4 57' 30" including: crinoids, tabulate and rugose corals, brachiopods, 100 Morrowan o 3 4 bryozoans, and blastoids. Conformable with the underlying Prairie Grove o Witter quadrangle location within the Boston Mountains. Prairie Grove Member of the Hale Formation. Shale. Ranges Hale S 5 from 30 to 40 feet (9 to 12 meters) thick. 3979 Cane Hill 7 o Hale Formation (Lower Pennsylvanian, Morrowan) - is Mississippian/Chesterian Pitkin 0 ft. 0 m Ùbb composed of interbedded sandstone, siltstone, shale, and JAPTON 4 MI. Introduction limestone units divided into two Members: the Prairie Grove Ùbp and the Cane Hill. Up to 160 feet (49 meters) thick. Harlow Hollow Monocline Ù bd Prairie Grove - thin to massive-bedded, very fine- to S This map depicts the bedrock and surficial geology of Ù unconformable sandstone cross-bedded shale hp medium-grained, limy sandstone or sandy limestone with o Q the 7.5-minute Witter quadrangle. In this area, approximately ls Ùat lenses of relatively pure fossiliferous and oolitic limestone. surface sandstone Ùat 940 feet (287 meters) of Mississippian (Chesterian) to 5 Light gray to light brown on fresh surfaces and weathers dark Ùa Pennsylvanian (Atokan) carbonate and clastic rocks are VENUS 2 MI. 39 S brown. Commonly cross-bedded, locally in a herringbone 78 exposed. These rocks formed from sediment deposited in distal Ùhc pattern. Honeycomb weathering is common. Fossils include: to near shore marine, tidal, deltaic, and fluvial environments. shale with calcareous limestone 5 crinoids, brachiopods, gastropods, tabulate and rugose corals, The quadrangle is situated on the northern part of the Boston siltstone sandstone ammonoids, and trilobites. Unconformable with the underlying o Mountains Plateau, the southernmost and highest of three Cane Hill. Ranges from 40 to 80 feet (12 to 24 meters) thick. 5 broad plateau surfaces in northern Arkansas known as the Cane Hill - interbedded, dark-gray silty shale, siltstone, Ozark Plateaus Province. This province is part of the Interior Ù (! (! o hc o and thin- to thick-bedded, very fine- to fine-grained, micaceous (! (! Highlands Physiographic Region and was developed by (! 4 (! sandstone. Tan to light gray on fresh surfaces, weathers tan to (! (! (! (! (! differential erosion of sedimentary units deposited on the (! Ù p gray. Flaser-bedding and ripple-bedding are common. Locally (! (! (! b (! (! (! (! ! (! (! ( flanks of the Ozark Dome, a volcanic structure formed during (! (! (! (! (! calcareous. The lower contact with the Pitkin Limestone is (! (! (! (! (! (! (! (! the Precambrian, which is centered in southeast Missouri. (! (! (! o (! (! (! unconformable and marks the Mississippian-Pennsylvanian (! 7255 IV NE IV 7255 (! (JAPTON) The Harlow Hollow Monocline and a small fault near (! (! 7255 I NE (! (! boundary in northern Arkansas. Just above this contact, a 2- (! (! (! (! o (! Slow Tom Hollow in War Eagle Creek are the only observed (! (! (! (! (! (! (! (WEATHERS) (! 6 o to 3-foot (0.6- to 0.9-meter)-thick conglomerate composed of (! (! (! structures in the mapped area. War Eagle Creek is a tributary (! (! Ù (! (! Ù o hp bd o black phosphate pebbles, gray to black limestone pebbles, (! 3 (! (! 7 to the White River which runs for approximately 13 miles (21 (! 3 o 5 oolitic limestone pebbles, oolitic phosphate pebbles, and (! Ùa kilometers) through the quadrangle and reveals excellent (! (! (! (! o crinoid fragments is locally present. Unconformable with the (!(! (! (! 3 4 (! exposures of bedrock. (! (! (!(! o (! (! underlying Pitken Limestone. Ranges from 40 to 80 feet (12 to (!(! (! (! (! (! Previous work in this area includes a geological (! 3 o 24 meters) thick. (! (! (! (! 7 (! (! (! (! (! worksheet by B. R. Haley, circa 1976, employing (!(! (! o (! (! (! (! (! (! (! photogeological methods and Master’s theses by R. A. Berry, (! (! (! (! (! o (! (! (! o (! (! (! 4 5 Pitkin Limestone (Upper Mississippian, Chesterian) - (! (! (! (! (! (! (! (! circa 1978, and M. R. Shinn, circa 1979. The current mapping (! (! ^ Mp micritic to coarsely crystalline, thin- to thick-bedded, (! (! 3976 5 3976 (! (! o project is based primarily on data collected from field (! (! (! 6 fossiliferous limestone. Light to dark gray on fresh and (! (! (!(! (!(! (! (! (! (!(! (! observations made between July, 2017 and February, 2018. (! (! 5 (! (!(! weathered surfaces. Exposures are limited to an area along (! (! (! Ùa (! (! These data, along with site locations, were recorded in a (! (! (! Qls (! (! Ù (! (! (! (! (! hc War Eagle Creek near Harlow Hollow. Up to10 feet (3 meters) (! (!(! (! (! (! 4 (! (! (! (! o (! (! (!(! (! (! (! ! geodatabase on a portable data collector/global positioning (!( (! (! ! 2 Ù thick. (!(! ( (! at (! (! (! (! (! o satellite receiver. Representative rock samples were collected at (! (! (! (! (! (! (! (! (! (! (! (! (! (! (! o Ù various sites to aid in classification and for future petrographic (! (!(! (! hp ( (! ! (! (! (! (! (! (! (! (! (!(! (!(! (! (! (! (! studies. (! (! (! (! (! Ù (! (! at (! (! (! (! (! 3 Qls (! (! (! (! (! (! (! o (! (! (! (! (! (! (! (!(! (! (! (! (! (! (!(! (! (! (! 39 39 (! (! (!(! (! 75 75 Description of Map Units (! (! (! (! (! (! (!(! (! (! T 15 N (! (! (! (! (! (! (! (! (! (! (! (! 55' (! (! (! (! (! (! (! Q 55' (! at Alluvium and terrace deposits (Quarternary) - (! (! (! (! Qat (! (! (! (! unconsolidated gravel, sand, silt, and clay deposited by (! (! (!(! (! (! (! (! (! (! (! (! (! T 14 N streams on one or more terrace levels. ! (! (! (! (! ( (! (! (! (! (!(! (! (! (! (! (! (! (! (! (! o T 15 N (! (! (! Landslide deposits (Quaternary) - unsorted,