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David T. Poynter

Publications and source records attributed to David T. Poynter.

3 recordsLinked to original sources
USGS1998

Altitude of the top of the Sparta Sand and Memphis Sand in three areas of Arkansas

The Sparta Sand and Memphis Sand form the second most productive aquifer in Arkansas. The Sparta Sand and Memphis Sand range in thick- ness from 0 to 900 feet, consisting of fine- to medium-grained sands interbedded with layers of silt, clay, shale, and minor amounts of lignite. Within the three areas of interest, the top surface of the Sparta Sand and Memphis Sand dips regionally east and southeast towards the axis of the Mississippi Embayment syncline and Desha Basin. Local variations in the top surface may be attributed to a combination of continued development of structural features, differential compaction, localized faulting, and erosion of the surface prior to subsequent inundation and deposition of younger sediments.

Water-Resources Investigations Report↗
USGS1994

Water-level maps of the Mississippi River Valley alluvial aquifer in eastern Arkansas, spring 1992

Water-level maps of the Mississippi River Valley alluvial aquifer are presented for spring 1992 in this map report. The alluvial aquifer consists of sand and gravel in flood-plain and terrace deposits of Quaternary age and supplies much of the water used for irrigation and aquaculture in eastern Arkansas. The map of the potentiometric surface, 5-year water-level change, and depth to water illustrates the effects of large with- drawals for irrigation on water levels in the aquifer. One large area of depression in the potentiometric surface, caused by large with- drawals of ground water for irrigation, occurs in Arkansas, Lonoke, and Prairie Counties, and another extends from Monroe County to western Craighead County.

Open-File Report↗