Distribution and clay mineralogy of organic-rich mud sediments in the Pamlico River estuary, North Carolina / by Thomas Scott Hartness.
| Author/creator | Hartness, Thomas Scott author. |
| Other author | Tien, Pei-lin, degree supervisor. |
| Other author | East Carolina University. Department of Geology. |
| Format | Theses and dissertations |
| Production | 1977. |
| Description | 45 leaves : illustrations, maps (3 folded in pocket) ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | The Pamlico River estuary is a funnel-shaped, oligohaline water body extending from the mouth of the Tar River southeastward where it empties into Pamlico Sound. This 50 km-long estuary formed from inundation of the easternmost Tar River drainage system by the rising of sea level during the Holocene transgression. The estuary floor is rather flat, and is composed of brown to black silty organic-rich mud. Sediment thickness data indicate that this mud is an infilling of the drowned stream valleys within the estuary. The distribution and thickness of the mud are primarily controlled by the geomorphical configuration of the infilled stream valleys. Greatest accumulations of the mud occur in the lowermost reaches of the estuary where it is probably more than 20 m thick. The mud is thickest in local areas overlying the deeper portions of the underlying sub-mud topography. The drowning and mud infilling of the eastern Tar-Pamlico drainage system has apparently migrated upstream through time in response to the rising of sea level. Clay mineralogical studies of the organic-rich mud indicate that the westernmost part of the estuary is characterized by a mixed kaolinite and dioctohedral vermiculite assemblege which decreases in abundance downstream. Illite and smectite occur in minor concentrations in the upper estuary, but increase in abundance downstream. Clay mineral assemblages of the mud in the lateral estuaries along the Pamlico are identical. with those found in mud sediments of adjacent open-water areas, suggesting a similar sediment source for both the trunk and lateral estuaries. The relative abundance of clay mineral species does not significantly change with depth in the mud. The concentration of organic matter in the mud is quite variable. Concentrations in the upper estuary and lateral estuaries are greatest, usually exceeding 15% by weight. Subsurface mud samples generally contain more organic matter than overlying surface sediments. The source of organic-rich mud is primarily fluvial in the upper estuary, but the lower estuary probably receives the greatest sediment input from erosion of local shoreline sediments and salt marsh peats. Transportation of muddy sediments from Pamlico Sound by wind-induced currents may also be an important source for the organic-rich mud. |
| General note | Presented to the faculty of the Department of Geology. |
| General note | Advisor: Pei-lin Tien |
| Dissertation note | M.A. East Carolina University 1977 |
| Bibliography note | Includes bibliographical references (leaves 31-34). |
| Genre/form | dissertations. |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Joyner | NC Stacks | QE389.625 .H3X | ✔ Available | Place Hold |
| Electronic Resources | Access Content Online | ✔ Available |