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J. E. Hazel

Publications and source records attributed to J. E. Hazel.

8 recordsLinked to original sources
USGS1999

Neogene-quaternary Ostracoda and paleoenvironments, of the Limón basin, Costa Rica, and Bocas del Toro basin, Panama

Tropical marine ostracodes from Neogene and Quaternary sediments of the Central American Caribbean region have been the subject of biostratigraphic, ecological, taxonomic, and evolutionary studies. As part of the Panama Paleontology Project (PPP), Neogene and Quaternary ostracodes are being studied from the Central American region. The overall goal of this research is to evaluate the impact of the emergence of the Central American Isthmus as a land barrier between the Caribbean/tropical Atlantic and the Pacific oceans on marine ostracode biodiversity and the oceanic environments in which extant ostracodes evolved. Due to the ecological specificity of many living tropical ostracode species, they are ideally suited for reconstructing paleoenvironments on the basis of their occurrence in fossil assemblages, which in turn can lead to a better understanding of the tropical climatic and tectonic history of Central America. The principal aims of this chapter are: (a) to document the composition of the ostracode assemblages from the Limón Basin of Costa Rica and the Bocas del Toro Basin of Panama, two areas yielding extensive ma rine ostracode assemblages; (b) to describe the environments of deposition within these basins; and (c) to document the stratigraphic distribution of potentially agediagnostic ostracode species in the Limón and Bocas del Toro basins in order to enhance their use in Central American biostratigraphy. A secondary, but none-the-less important goal is to assemble a database on the distribution of modem ostracode species in the Caribbean and adjacent areas as a basis for comparison with fossil assemblages. Although the ecological, biostratigraphic and paleoenvironmental conclusions presented here will improve as additional material is studied, these fossil and modem ostracode databases constitute the foundation for future evolutionary and geochernical studies of tropical Caribbean and eastern Pacific Ocean ostracodes. Moreover, we present here evidence that major faunal and oceanic changes occurred in the westem Caribbean over the last 4 million years, probably related to changes in ocean circulation due to the emergence of the Isthmus as well as other climatic events.

Bulletins of American Paleontology↗
USGS1984

Age and correlation of emerged pliocene and pleistocene deposits, U.S. Atlantic Coastal Plain

Paleontologic and paleomagnetic investigations were conducted on several hundred Pliocene and Pleistocene marine samples from five regions of the emerged Atlantic Coastal Plain: (1) the Delmarva Peninsula, (2) eastern Virginia, (3) central and northern North Carolina, (4) southern North Carolina and northeastern South Carolina, and (5) the Charleston area, South Carolina. Molluscan and ostracode interval and assemblage zonations, which are the primary means of regional correlation, have been calibrated using planktic biochronologic, paleomagnetic, radiometric and amino-acid recemization data. These multiple dating criteria were used to determine the age and, where possible, the duration of marine transgressive/regressive sequences. A correlation chart illustrates the age relationships of 27 formations from five regions. One important conclusion is some of the Yorktown Formation of Virginia and North Carolina (including the “Duplin” Formation), and some of the Raysor of South Carolina are late Pliocene in age. The late Pliocene Chowan River Formation of North Carolina is older than the early Pleistocene Waccamaw Formation of South Carolina, which in turn may be older than the James City Formation of North Carolina. During the last 1.0 million years, multiple marine transgressions occurred in each region, but the age of these middle and late Pleistocene formations often may differ from one area to the next. A significant result of the study is the evidence for the lack of time equivalence of formations in the five different regions; that is, the sequence of marine transgressions in one region does not necessarily correspond to that in another. This appears to be the result of differing subsidence and uplift histories, the patchiness of the depositional record, and the limitations of the dating techniques in light of the rapidity and frequency of sea-level fluctuations.

Delaware, Maryland, North Carolina, South Carolina↗
USGS1984

Age of the Comfort Member of the Castle Hayne Formation, North Carolina

The biostratigraphic and chronostratigraphic position of the Comfort Member of the Castle Hayne Formation has been the subject of much debate. At the Martin-Marietta Quarry at Castle Hayne, New Hanover County, North Carolina, the planktic foraminifers indicate an assignment within an interval of the uppermost Turborotalia frontosa Zone to the Turborotalia pomeroli Zone. The calcareous nannofossils indicate an assignment to the middle part of the Chiasmolithus solitus Zone. The dinocyst data indicate placement in the upper part of the Kisselovia coleothrypta Zone of Costa and Downie. These zonal units are considered to be within the middle Eocene of international usage, and, on the basis of the time scale used in this paper, the Chiasmolithus solitus Zone represents a time interval of 42.1 to 45.4 megaannums (Ma). This differs significantly from a Rb/Sr glauconite date of 34.8 ± 1.0 Ma previously obtained at the same locality.

North Carolina↗
USGS1982

Biostratigraphy and paleoecology of lower Paleozoic, upper Cretaceous, and lower Tertiary rocks in U.S. Geological Survey New Madrid test wells, Southeastern Missouri

The paleontology and biostratigraphy of Tertiary, Cretaceous, and Paleozoic rocks in the upper Mississippi embayment are incompletely known because marine fossils are only locally present in these rocks. This study concerns material from two U.S. Geological Survey test wells drilled in New Madrid County, southeastern Missouri, as part of earthquake hazard studies in the northern Mississippi Embayment. Test well1 sampled lower Tertiary strata to a depth of 146ft; these strata were found to be late Eocene in age on the basis of sporomorphs. Test well1-X, 29ft northwest of well1, provided cuttings and cores from lower Tertiary, Upper Cretaceous, and lower Paleozoic rocks to a total depth of 2,316 ft below the Kelly bushing (at an altitude of 288 ft). Lithologic evidence suggests that the base of the Jackson Formation may be at 270 ft, but sporomorphs indicate that the base of the Jacksonian Stage (upper Eocene) is possibly at a depth of about 350ft in test well1-X. Lithologic units of the Claibornian Stage (middle Eocene) here consist of the Cockfield(?) and Cook Mountain(?) Formations and Memphis Sand, in descending order. The Claibornian could not be subdivided using sporomorphs from cuttings, but sporomorphs show that the top of the Sabinian Stage (top of the lower Eocene) is at about 1,055 ft; lithologically, the top of the Wilcox Group (top of the Flour Island Formation) is at 1,048 ft. Sporomorphs suggest that the top of the lower Sabinian (top of the Paleocene) is within the Flour Island Formation at about 1,105 ft. The next major lithologic break, the top of the Fort Pillow Sand at 1,186 ft, does not coincide with any detectable biostratigraphic boundary. Lithologically, the interval from 1,339 to 1,377 ft may belong to the Old Breastworks Formation; dinoflagellates from cuttings indicate that this interval is likely to be late Midwayan in age and, therefore, correlative with the Naheola Formation of the eastern Gulf Coast. The Porters Creek Clay extends from a probable top at 1,377 ft to 1,691 ft, and the base of the underlying Clayton Formation (Tertiary-Cretaceous contact) is at 1, 703 ft. Calcareous nannofossils, dinoflagellates, foraminifers, mollusks, ostracodes, and sporomorphs from continuous cores of the Porters Creek Clay and Clayton Formation indicate that the upper half of the Porters Creek correlates with the upper part of the same formation or perhaps partly with slightly younger rocks in the eastern Gulf Coast, the lowermost Porters Creek appears to correlate with the upper part of the Clayton Formation of the eastern Gulf Coast and with the Kincaid Formation of Texas, and the thin Clayton of the test well probably correlates with only the lower part of the thicker Clayton of the eastern Gulf Coast. Sporomorphs from McNairy Sand (Upper Cretaceous) cores indicate Maestrichtian and perhaps latest Campanian Age. Lower Paleozoic dolostone from 2,023 ft to total depth at 2,316 ft is barren of identifiable fossils except for a probable fragment of the fish Anatolepis; the dolostone is probably Late Cambrian in age. The McNairy Sand of New Madrid well 1-X seems to have been deposited in nonmarine to nearshore marine environments; the Clayton Formation and lower part of the Porters Creek Clay were deposited under marine conditions during an early Paleocene marine transgression. A major regression followed that continued through the end of Porters Creek time and perhaps into Naheola (late Midwayan) time; the Sabinian, Claibornian, and Jacksonian strata in southeastern Missouri were deposited primarily or entirely in nonmarine environments.

Missouri↗
USGS1981

Quaternary climates and sea levels of the U.S. Atlantic Coastal Plain

Uranium-series dating of corals from marine deposits of the U.S. Atlantic Coastal Plain coupled with paleoclimatic reconstructions based on ostracode (marine) and pollen (continent) data document at least five relatively warm intervals during the last 500,000 years. On the basis of multiple paleoenvironmental criteria, we determined relative sea level positions during the warm intervals, relative to present mean sea level, were 7 ± 5 meters at 188,000 years ago, 7.5 ± 1.5 meters at 120,000 years ago, 6.5 ± 3.5 meters at 94,000 years ago, and 7 ± 3 meters at 72,000 years ago. The composite sea level chronology for the Atlantic Coastal Plain is inconsistent with independent estimates of eustatic sea level positions during interglacial intervals of the last 200,000 years. Hydroisostatic adjustment from glacial-interglacial sea level fluctuations, lithospheric flexure, and isostatic uplift from sediment unloading due to erosion provide possible mechanisms to account for the discrepancies. Alternatively, current eustatic sea level estimates for the middle and late Quaternary may require revision.

Atlantic Coastal Plain↗
USGS1978

Orthogonal mapping: A computer program for quantifying shape differences

Quantitative differences in the shape of two or more objects can be obtained by Orthogonal Mapping provided coincidental or analogous points can be identified on each object. The least-squares difference between each set of analogous points is determined by use of a projective transformation of a set of measured points which involves the rotation, translocation, and scaling of these points relative to a set of fixed points. ?? 1978.

Computers & Geosciences↗