Late cretaceous (Campanian and Maastrichtian) sequence stratigraphy, southeastern North Carolina, USA
- UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
- Jessica A. Pierson (Creator)
- Institution
- The University of North Carolina Wilmington (UNCW )
- Web Site: http://library.uncw.edu/
- Advisor
- William Harris
Abstract: Sequence stratigraphic analysis using samples, geophysical logs, and biostratigraphic data from
U.S.G.S. core holes Kure Beach, Hilton Park, and Black Rock Landing identified four partial or
complete Late Cretaceous sequences. Sequence 1 (Campanian) is dominated by dirty calcareous
sand. Mean sand size is 1.93 f; mean carbonate wt. % is 25.9%. This partial sequence is
interpreted as a highstand systems tract (HST). A Type-1 sequence boundary separates
Sequence 1 from the next sequence; it is reflected by an irregular surface and the absence of
calcareous nannofossil zones CC24 and CC25a. Sequence 2 (Maastrichtian) is characterized in
its lower part by clean, fining-upward (1.7 f to 3.4 f) calcareous sand interpreted as a lowstand
wedge (LSW). The LSW is overlain by a grainstone followed by calcareous sand with a mean
sand size of 2.92 f and a mean wt. % carbonate of 65.2%, interpreted as a transgressive systems
tract (TST). The overlying HST is dominated by intercalated muddy carbonate, skeletal
grainstone, and mollusk-fragment carbonate sand. Mean sand size is 2 f; mean wt. % carbonate
is 39.3%. A Type-2 sequence boundary separates Sequence 2 from the next sequence. Sequence
3 consists of a basal coarsening-upwards calcareous sand that is interpreted as a shelf margin
deposit (SMST). Mean sand size is 2.63 f; mean wt. % carbonate is 34.1%. A sharp contact
separates the SMST from the overlying TST. Mean grain size fines to 3.12f and mean wt. %
carbonate increases to 47.4%. The condensed interval (CI) occurs where sediment size is the
finest; no hardgrounds are present. The overlying HST consists of a lower parasequence that
shoals upward from muddy to sandy carbonate with evidence of storm winnowing. Mean grain
size is 2.64 f; mean wt. % carbonate is 51.8%. The younger parasequence shoals to a sandy,
pelecypod-mold grainstone. Mean sand size is 1.64 f; mean wt % carbonate is 56.7 %. A
dissolution surface above the grainstone represents the 68 Ma unconformity. The youngest sequence (4) has variable lithology. The Cretaceous parts consist of a nearly pure carbonate
overlain by muddy sand. Mean sand size is 2.61 f; mean weight % carbonate is 26.9
Late cretaceous (Campanian and Maastrichtian) sequence stratigraphy, southeastern North Carolina, USA
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Created on 1/1/2009
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Additional Information
- Publication
- Thesis
- A Thesis Submitted to the University of North Carolina Wilmington in Partial Fulfillment of the Requirements for the Degree of Master of Arts
- Language: English
- Date: 2009
- Keywords
- Geology--North Carolina--Black Rock Landing, Geology--North Carolina--Hilton Park, Geology--North Carolina--Kure Beach, Geology, Stratigraphic--Cretaceous
- Subjects
- Geology, Stratigraphic -- Cretaceous
- Geology -- North Carolina -- Kure Beach
- Geology -- North Carolina -- Hilton Park
- Geology -- North Carolina -- Black Rock Landing