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D.C. Prowell

Publications and source records attributed to D.C. Prowell.

15 recordsLinked to original sources

A palynological biozonation for the uppermost Santonian and Campanian Stages (Upper Cretaceous) of South Carolina, USA

Five palynological biozones are proposed for the uppermost Santonian and Campanian Stages of South Carolina. In ascending stratigraphic order, these highest-occurrence interval zones are the Osculapollis vestibulus (Ov) Biozone, the Holkopollenites propinquus (Hp) Biozone, the Holkopollenites forix (Hf) Biozone, the Complexiopollis abditus (Ca) Biozone, and the Osculapollis aequalis (Oa) Biozone. These biozones are based on an analysis of more than 400 subsurface and outcrop samples throughout the Coastal Plain Province of South Carolina, and the adjacent states of Georgia and North Carolina. Integration of the biostratigraphy with lithostratigraphy and geophysical log data suggests that the lower and upper boundaries of each biozone are bounded by regional unconformities. Five new species are described, and an emendation is presented for one additional species. ?? 2009 Elsevier Ltd.

Cretaceous Research

The chrono- and lithostratigraphic significance of the type section of the Middendorf Formation, Chesterfield County, South Carolina

The name Middendorf Formation has been widely used in the Coastal Plain of South Carolina, eastern Georgia, and southern North Carolina since 1904, despite conflicting interpretations of the age and stratigraphic relations of the unit at its type locality. Between 1995 and 1998, the U.S. Geological Survey, in cooperation with the South Carolina Department of Natural Resources, drilled three continuously cored holes to the south and to the east of the type section of the Middendorf Formation, which is located in Chesterfield County, South Carolina. In addition, two outcrops to the northeast of the type section were sampled for biostratigraphic control. The litho- and biostratigraphic relations of the units in these cores and outcrops provide significant insights into the age of the Middendorf Formation at its type locality, and how this age impacts regional correlations of the formation. A projection of formational contacts and thicknesses from downdip areas into the type locality of the Middendorf Formation indicates that the type section is most likely a facies of either the uppermost Bladen Formation (of the Black Creek Group), or the uppermost Bladen and the lowermost part of the Peedee Formations. This report documents the evidence that support this interpretation. The implication of this interpretation is that the name "Middendorf" has been applied to a variety of units throughout the southeastern United States, all of which display a similar lithology, but differ significantly in stratigraphic position and age. For these reasons, we recommend that the name Middendorf be restricted for use with strata that occur only in the vicinity of the type locality, and use of the name "Middendorf" for units elsewhere in the Coastal Plain be reconsidered.

Southeastern Geology

A palynological biozonation for the Maastrichtian Stage (Upper Cretaceous) of South Carolina, USA

Three palynological biozones are proposed for the Maastrichtian Stage of South Carolina. In ascending stratigraphic order, the biozones are the Carolinapollis triangularis (Ct) Interval Biozone, the Holkopollenites chemardensis (Hc) Interval Biozone, and the Sparganiaceaepollenites uniformis (Su) Interval Biozone. Integration of the biostratigraphy with lithologic and geophysical log data suggests that within the study area, the upper and lower boundaries of each zone are bounded by regional unconformities, and that a three-fold subdivision of the Maastrichtian Stage is warranted. The biozonation is based on the analysis of 114 samples from 24 subsurface and three outcrop sections from the Coastal Plain of South Carolina; samples from an additional seven subsurface and 18 outcrop sections from North Carolina and Georgia were examined to evaluate the geographic extent of the biozones. One new genus and five new species of pollen are described, and emendations are presented for two genera and one species of pollen. ?? 2003 Published by Elsevier Science Ltd.

Cretaceous Research

Evidence for large-scale reworking of Campanian sediments into the Upper Maastrichtian Peedee formation at Burches Ferry, South Carolina

A 44-ft-deep corehole (FLO-311) was drilled at Burches Ferry, Florence County, S.C., in order to document the lithologic and paleontologic characteristics of the boundary between the upper Campanian Donoho Creek Formation and the upper Maastrichtian Peedee Formation. Palynomorph and calcareous nannofossil data provide detailed age control for these sediments. Examination of calcareous nannofossil assemblages shows that sediments from the type locality of the Peedee Formation consist largely of reworked Campanian materials. Robust Campanian species such as Reinhardtites anthophorus, Reinhardtites levis, and Stoverius asymmetricus commonly are found reworked into the Maastrichtian Peedee Formation in its entirety. Therefore, identification of lower upper Maastrichtian sediments is based on the presence of background assemblages rather than on the more traditional marker species. The presence of species restricted to the latest Campanian at the Donoho Creek-Peedee contact in outcrop indicates that the entire sedimentary package represented by calcareous nannofossil Zones CC23 and CC24 has been removed.

Southeastern Geology

Physical stratigraphy, paleontology, and magnetostratigraphy of the USGS-Santee Coastal Reserve core (CHN-803), Charleston County, South Carolina

The Santee Coastal Reserve core, a 545-ft-deep corehole in northeastern Charleston County, South Carolina, recovered sediments of Late Cretaceous, Paleocene, Eocene, and Quaternary age. The deepest sediments, the Donoho Creek Formation (545-475.7 ft), consist of 69.3 ft of muddy calcareous sand of marine origin. This formation is placed within the upper Campanian calcareous nannofossil Subzone CC 22c. The overlying Peedee Formation (475.7-367.1 ft) in the core consists of 108.6 ft of silty clay of marine origin. It is placed in upper Maastrichtian calcareous nannofossil Subzones CC 25b, CC 26a, and CC 26b. Combined fossil and paleomagnetic information indicates nearly continuous deposition. Foraminifers indicate an outer neritic paleobathymetric setting. The Rhems Formation sensu stricto (367.1-267.3 ft) consists of 99.8 ft of silty clay, muddy sand, and minor calcite-cemented, shelly sand of marine origin. It is apparently the product of rapid sediment accumulation during a short period of time in the early Paleocene (calcareous nannofossil Zone NP 1). The upper part of the Rhems Formation sensu Bybell and others (1998) (267.3-237.4 ft) consists of 29.9 ft of calcite-cemented muddy sand and burrowed fine sand of marine origin. It is placed in calcareous nannofossil Zone NP 4 and, because it shows normal polarity, likely represents the upper part of the lower Paleocene. This unit may be correlative with the lower part of the Lower Bridge Member of the Williamsburg Formation in its type area. The Lower Bridge Member of the Williamsburg Formation (237.4-125.0 ft) has an unconformable contact at 205.0 ft that divides the member into lower muddy sand beds and upper calcareous clay beds. Both are placed in the upper Paleocene calcareous nannofossil Zone NP 5. The Chicora Member of the Williamsburg Formation (125-51.5 ft) consists of 73.5 ft of muddy, shelly sand of marine origin. It is poorly dated but includes late Paleocene nannofossils (Zones NP 5 and NP 6). A mollusk-bryozoan limestone (51.5-42.0 ft) above the Chicora Member of the Williamsburg yields early Eocene calcareous nannofossils representing both Zone NP 9/10 and Zone NP 12, together with pollen and dinocysts that are younger. Sediments of middle and late Eocene, Oligocene, Miocene, and Pliocene ages were not recovered in the Santee Coastal Reserve core. The upper 42.0 ft of sediments represent Quaternary deposits and are included in the Wando Formation (42.0-28.0 ft) and the informal Silver Bluff beds (28.0-0 ft).

South Carolina

Physical stratigraphy, paleontology, and magnetostratigraphy of the USGS-Santee Coastal Reserve core (CHN-803), Charleston County, South Carolina

The Santee Coastal Reserve core, a 545-ft-deep corehole in northeastern Charleston County, South Carolina, recovered sediments of Late Cretaceous, Paleocene, Eocene, and Quaternary age. The deepest sediments, the Donoho Creek Formation (545-475.7 ft), consist of 69.3 ft of muddy calcareous sand of marine origin. This formation is placed within the upper Campanian calcareous nannofossil Subzone CC 22c. The overlying Peedee Formation (475.7-367.1 ft) in the core consists of 108.6 ft of silty clay of marine origin. It is placed in upper Maastrichtian calcareous nannofossil Subzones CC 25b, CC 26a, and CC 26b. Combined fossil and paleomagnetic information indicates nearly continuous deposition. Foraminifers indicate an outer neritic paleobathymetric setting. The Rhems Formation sensu stricto (367.1-267.3 ft) consists of 99.8 ft of silty clay, muddy sand, and minor calcite-cemented, shelly sand of marine origin. It is apparently the product of rapid sediment accumulation during a short period of time in the early Paleocene (calcareous nannofossil Zone NP 1). The upper part of the Rhems Formation sensu Bybell and others (1998) (267.3-237.4 ft) consists of 29.9 ft of calcite-cemented muddy sand and burrowed fine sand of marine origin. It is placed in calcareous nannofossil Zone NP 4 and, because it shows normal polarity, likely represents the upper part of the lower Paleocene. This unit may be correlative with the lower part of the Lower Bridge Member of the Williamsburg Formation in its type area. The Lower Bridge Member of the Williamsburg Formation (237.4-125.0 ft) has an unconformable contact at 205.0 ft that divides the member into lower muddy sand beds and upper calcareous clay beds. Both are placed in the upper Paleocene calcareous nannofossil Zone NP 5. The Chicora Member of the Williamsburg Formation (125-51.5 ft) consists of 73.5 ft of muddy, shelly sand of marine origin. It is poorly dated but includes late Paleocene nannofossils (Zones NP 5 and NP 6). A mollusk-bryozoan limestone (51.5-42.0 ft) above the Chicora Member of the Williamsburg yields early Eocene calcareous nannofossils representing both Zone NP 9/10 and Zone NP 12, together with pollen and dinocysts that are younger. Sediments of middle and late Eocene, Oligocene, Miocene, and Pliocene ages were not recovered in the Santee Coastal Reserve core. The upper 42.0 ft of sediments represent Quaternary deposits and are included in the Wando Formation (42.0-28.0 ft) and the informal Silver Bluff beds (28.0-0 ft).

Open-File Report

Effect of faults on fluid flow and chloride contamination in a carbonate aquifer system

A unified, multidiscipline hypothesis is proposed to explain the anomalous pattern by which chloride has been found in water of the Upper Floridan aquifer in Brunswick, Glynn County, Georgia. Analyses of geophysical, hydraulic, water chemistry, and aquifer test data using the equivalent porous medium (EPM) approach are used to support the hypothesis and to improve further the understanding of the fracture-flow system in this area. Using the data presented herein we show that: (1) four major northeast-southwest trending faults, capable of affecting the flow system of the Upper Floridan aquifer, can be inferred from structural analysis of geophysical data and from regional fault patterns; (2) the proposed faults account for the anomalous northeastward elongation of the potentiometric surface of the Upper Floridan aquifer; (3) the faults breach the nearly impermeable units that confine the Upper Floridan aquifer from below, allowing substantial quantities of water to leak vertically upward; as a result, aquifer transmissivity need not be excessively large (as previously reported) to sustain the heavy, long-term pumpage at Brunswick without developing a steep cone of depression in the potentiometric surface; (4) increased fracturing at the intersection of the faults enhances the development of conduits that allow the upward migration of high-chloride water in response to pumping from the Upper Floridan aquifer; and (5) the anomalous movement of the chloride plume is almost entirely controlled by the faults.

Georgia