Jackfork Sandstone (ARPAj;0)

State	Arkansas
Name	Jackfork Sandstone
Geologic age	Phanerozoic \| Paleozoic \| Carboniferous Pennsylvanian-Early [Morrowan]
Original map label	&j
Comments	Sandstone with interbedded shale, some as olistolithic intervals. Approximately 6000 ft. maximum thickness.
Primary rock type	sandstone
Secondary rock type	shale
Other rock types
Lithologic constituents	Major Sedimentary > Clastic > Mudstone > Shale (Bed) Sedimentary > Clastic > Sandstone (Bed)
Map references	Haley, B. R., Glick, E. E., Bush, W. V.; Clardy, B. F.; Stone, C. G.; Woodward, M. B., Zachry, D.L., 1993, Geologic Map of Arkansas: U.S.Geological Survey Special Geologic Map. Scale 1:500K
Unit references	Moore, R. C., 1934, The origin and age of the boulder-bearing Johns Valley shale in the Ouachita Mountains of Arkansas and Oklahoma: American Journal of Science, vol.27, no.162, pp.432-453 Stone, C. G. and Bush, W. V. 1982, Summary of the geology of the eastern Ouachita Mountains, Arkansas: Guidebook - Arkansas Geological Commission, vol.82-2, 24 pp.
Geographic coverage	Clark - Faulkner - Garland - Hot Spring - Howard - Montgomery - Perry - Pike - Polk - Pulaski - Saline - Scott - Sevier - Yell