Download or read book Foraminiferal Sedimentological and Geochemical Indications of Holocene Environmental Change in Pamlico Sound North Carolina written by Jennifer A. Foley and published by . This book was released on 2007 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic and Trace element Content of Holocene Sediments in Two Estuarine Bays Pamlico South Area North Carolina written by Henry Lee Berryhill (Jr.) and published by . This book was released on 1972 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The distribution and interrelations of total organic matter and soluble organic components in sand and mud deposited in shallow brackish-water parts of the large complex Pamlico Sound estuarine environment.
Download or read book America s Most Vulnerable Coastal Communities written by Joseph T. Kelley and published by Geological Society of America. This book was released on 2009-01-01 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Sea level is rising, and yet Americans continue to develop beaches with little regard. In this volume, a group of coastal geologists discusses the startling saga of ten U.S. East and Gulf Coast shoreline communities (plus Puerto Rico and some western Europe strands) and the problems created by their inevitable interaction with natural processes in this highly dynamic geologic environment. The authors discuss the geologic context of the hazards of each site as the history of societal responses and their environmental impacts. Response to the natural coastal processes that threaten lives and buildings is carried out in a context of local, state and national politics with fixed short-term engineering solutions (beach replenishment, seawalls) generally favored over longer-term approaches (moving back, prohibition of seawalls). This essential GSA Special Paper foreshadows the impending rise of sea level and the myriad of shoreline responses and political controversies it will provoke."--Publisher's description.
Download or read book Holocene Stratigraphy and Paleoenvironmental Change of Pamlico Sound North Carolina USA written by Nicholas Zaremba and published by . This book was released on 2014 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: Holocene Stratigraphy and Paleoenvironmental Change of Pamlico Sound, North Carolina, USA by Nicholas Zaremba September, 2014 Directors of Thesis: David Mallinson and Eduardo Leorri Major Department: Geological Sciences. Understanding how coastal systems respond to changes in climate is becoming more important due to the current increased rate of sea-level rise and possible increased hurricane intensity in the future. While coastal ecosystems represent only 10% of Earth's surface, more than 20% of the world's population resides within 100 km of the coastline and within 100 m of sea level, which highlights the need to understand the past effects of sea-level rise and climate change on barrier island systems. In North Carolina, USA the barrier island system in the northern portion of the state (the Outer Banks) extends for ca. 270 km of the state's coast and provides a dynamic boundary between the ocean and two large estuarine water bodies, Albemarle and Pamlico Sound. This study expands upon previous work which identified two periods of increased marine influence within Pamlico Sound interpreted to be the result of extensive barrier island segmentation synchronous with periods of rapid climate change (RCC) during the late Holocene. Approximately 470 km of high resolution geophysical data, 850 bulk sediment magnetic susceptibility sediment samples and ca. 600 sediment analyses were constrained by 108 radiocarbon age estimates derived from 52 vibracores to better understand the Holocene stratigraphy of Pamlico Sound and how the periods of RCC affected the stratigraphic architecture of the Sound. According to previous work, estuarine waters prevailed within the paleovalleys of Pamlico Sound as early as ca. 7500 cal BP and Pleistocene interfluves provided protection for the paleovalleys from the Atlantic Ocean until ca. 5500 cal BP, when the interfluves were flooded by rising sea-level, this interpretation is based on a conservative sea-level rise. However, the data provided in this study indicates that there is no evidence of a change in depositional environment at ca. 5500 cal BP. If the 5500 cal BP flooding of the Pleistocene interfluves is accurate, then Holocene barrier islands must have been present to explain the presence of estuarine deposits within the paleovalleys. At ca. 4000 cal BP, an increase in marine influence and sand content is detected in multiple cores within the northern basin and is interpreted to be the result of increased segmentation of barrier islands. This deposit is mainly recorded within the paleovalleys of Pamlico Sound; and is only preserved on a few interfluves as a result of base level being too low. Reformation of the barrier islands occurred sometime from 3500 to 2500 cal BP; suggested by muddy deposits with low brackish estuarine foraminiferal assemblages. At ca. 1200 cal BP, a sudden increase in marine influence is detected throughout southeastern Pamlico Sound; a sandy deposit is interpreted to be the result of extensive segmentation of the barrier islands during the Medieval Climate Anomaly (MCA). Geophysical data suggests the segmentation of the barriers was large in magnitude to allow for deposition of large lobate shoals (the MCA shoals). Further refinement of a local sea-level curve is required to understand the mechanisms responsible for the 4000 cal BP marine influenced deposit. The error range of the North Carolina sea-level curve loosely constrain the initial flooding of the Pleistocene interfluves anytime from 5500 to 4000 cal BP rather than before 7000 cal BP as previously postulated. Therefore, it is difficult to hypothesize about the mechanism responsible for the 4000 cal BP sandy deposit without a more refined local sea level curve. However, data from this study combined with other research suggest that the 1200 cal BP deposit was likely caused by an increase in hurricane activity or intensity during the MCA. Furthermore this study has provided an estimate on the volume (1.1x109 km3) of silt and clay deposited within the northern basin of Pamlico Sound since ca. 4000 cal BP; this has aided in creating a carbon sequestration budget for the system.
Download or read book Holocene Paleoenvironmental Change in Pamlico Sound North Carolina written by Candace A. Grand Pre and published by . This book was released on 2006 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Holocene Paleoenvironental Change in Southern Pamlico Sound North Carolina written by M. Lauren Metger and published by . This book was released on 2009 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Late Holocene Evolution of Currituck Sound North Carolina USA written by Kelli Moran and published by . This book was released on 2012 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coastal evolution is an increasingly important area of study, especially with the projected rise in sea level, increase in storm intensity, and population increases along the nation's coasts. In order to predict how the coastal environment will respond to these changes in the future, we need to first understand the evolution of coastal systems in the past. Here I address the late Holocene evolution of Currituck Sound, North Carolina, by examining time periods with different barrier island and inlet configurations interpreted from core data. Chirp seismic data and 13 vibracores have been used to interpret the Holocene development of this region. Four depositional units have been defined, based on lithofacies, biofacies, geophysical, and geochronologic data. The lowermost depositional unit (Unit I) is represented by quartz sand, barren of foraminifera, and is Pleistocene in age based on an OSL age estimate of 33.7 ka. Unit II consists of slightly muddy sand that fines upward to slightly sandy mud; it is barren of foraminifera, contains rooted horizons in several cores, and is interpreted as a fresh water swamp forest deposit (radiocarbon dating provide age estimates of ca. 4000 to 2800 cal y BP). Unit III is characterized by slightly sandy mud to mud containing a calcareous foraminiferal assemblage and oyster bioherms; these characteristics indicate a back-barrier estuarine environment with high salinity (ca. 25 to 35) due to open inlets in the barrier islands to the east. Radiocarbon age estimates for Unit IV range from ca. 1700 to 500 cal y BP. The topmost unit (Unit IV) is composed of sediment with variable composition, ranging from clean quartz sand to mud, and contains foraminiferal assemblages that are generally mixed calcareous/agglutinated at the base overlain by entirely agglutinated assemblages. This unit represents the modern (post- ca. 1827), mid- to low salinity (less than 10), back-barrier lagoon with no inlets open in the barrier island. Sediment and microfossil-based paleoenvironmental and geomorphic reconstructions, including variable numbers of inlets, have been used as input into the Delft3D hydrodynamic model to understand inlet related changes to tides and currents within the Sound. This modeling indicates that impacts of inlets are very localized and only inlets in the direct vicinity of Currituck Sound (i.e., between historic Caffey's Inlet and Kill Devil Hills) have a significant impact on the water levels and currents in the study area.
Download or read book Reconstruction of the Recent Paleoenvironment of Pamlico Sound North Carolina Using Foraminifera Stable Isotopes delta 13C delta 15N and Radionuclide Data written by Irene Johanna Abbene and published by . This book was released on 2004 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using Sediment Organic Geochemistry to Interpret Late Holocene Barrier Island and Estuarine Evolution North Carolina USA written by Jeffrey J. Minnehan and published by . This book was released on 2014 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Deconvolving the relationship between meteorological and oceanographic phenomena and associated impacts to coastal systems is critical to understanding the future of coastal systems worldwide. North Carolina's barrier islands, commonly known as the Outer Banks, and the associated Albemarle-Pamlico estuarine system is an example of a coastal ecosystem that will be affected in the future by such phenomena. Based on sedimentological and micropaleontological proxies, past research suggests that intense storm activity may have caused extensive segmentation of the Outer Banks during the Holocene. To gain a better understanding of meteorological and oceanographic factors affecting the evolution of North Carolina's coastal system, organic geochemical techniques were applied to sediments from two cores collected within Pamlico Sound. Specifically, down-core trends in total organic carbon (TOC), refractory black carbon (BC), refractory soot carbon, labile organic carbon (OC), total nitrogen (TN), and their stable isotopic signatures ([delta]13C and [delta]15N) were analyzed in order to assess the varying inputs of marine and terrestrial organic matter into Pamlico Sound. In Chapter 1, TOC, BC/TOC, soot/TOC, TOC/TN, and [delta]13C[subscript]TOC were compared to a paleoclimatological proxy of El Niño Southern Oscillation (ENSO) and interpretations of stages of the North Atlantic Oscillation (NAO) throughout the mid-to-late Holocene. These phenomena have been suggested to influence southeast U.S. temperature, precipitation, and Atlantic hurricanes, all of which ultimately affect barrier island and estuarine evolution, as recorded in Pamlico Sound sediments. In general, there has been little consideration of carbon sequestered in coastal systems throughout the Holocene, a period that shows anthropogenic changes in the carbon cycle. This is an important omission, as most of the sediments exported by the world's major rivers are currently deposited on continental shelves (e.g., deltas and estuaries). Chapter 2 examines how the degree of barrier island segmentation affects abundance and source of carbon sequestered in Pamlico Sound throughout the mid-to-late Holocene. Total organic carbon sequestered in Pamlico Sound was calculated over the past 3500 years. Since the ultimate fate of TOC depends on its composition (e.g., whether it is labile or refractory), both OC and BC in sediments were quantified down-core. Results show that greater continuity of a barrier island chain significantly increased the amount of carbon sequestered in sediments. To our knowledge, this chapter provides the first quantitative estimate of the amount of carbon sequestered as a function of its composition since the mid-Holocene in any coastal system. The results of both chapters suggest that ENSO, NAO, eastern North Carolina temperature and precipitation, Atlantic storm activity, Outer Banks barrier island evolution, and coastal carbon sequestration were linked throughout the mid-to-late Holocene.
Download or read book Sedimentary Geochemistry of Central Pamlico Sound North Carolina written by Thomas Oscar Wright and published by . This book was released on 1974 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic and Trace Element Content of Holocene Sediments in Two Estuarine Bays Pamlico Sound Area North Carolina written by Geological Survey (U.S.) and published by . This book was released on 1969 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: The distribution and interrelations of total organic matter and soluble organic components in sand and mud deposited in shallow brackish-water parts of the large complex Pamlico Sound estuarine environment.
Download or read book Organic and Trace element Content of Holocene Sediments in Two Estuarine Bays Pamlico South Area North Carolina written by Henry Lee Berryhill (Jr.) and published by . This book was released on 1972 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The distribution and interrelations of total organic matter and soluble organic components in sand and mud deposited in shallow brackish-water parts of the large complex Pamlico Sound estuarine environment.
Download or read book Time Series of Living Benthic Foraminifera in Pamlico Sound North Carolina written by Valerie Martin Peterson and published by . This book was released on 2006 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Petroleum Abstracts written by and published by . This book was released on 1971 with total page 1314 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Late Holocene Climate Variability from Northern Gulf of Mexico Sediments written by Julie N. Richey and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Accurate reconstruction of natural climate variability over the past millennium is critical for predicting responses to future climate change. In order to improve on current understanding of climate variability in the sub-tropical North Atlantic region over the past millennium, a rigorous study of Gulf of Mexico (GOM) sea surface temperature (SST) variability was conducted using both inorganic (foraminiferal Mg/Ca) and molecular organic (TEX6) geochemical proxies. In addition to generating multiple high-resolution climate records, the uncertainties of the SST proxies are rigorously assessed. There are 3 major research questions addressed: (1) What was the magnitude of GOM SST variability during the past 1,000 years, particularly during large-scale climate events such as the Little Ice Age (LIA) and the Medieval Warm Period (MWP). (2) Is the SST signal reproducible within the same sediment core, among different northern GOM basins, and using different geochemical SST proxies? (3) What are the ecological controls on the paleothermometers used to reconstruct SST variability in the GOM? Can differences in the ecology (i.e. seasonal distribution, depth habitat, etc.) of distinct paleothermometers be exploited to gain insight into changes in upper water column structure or seasonality in the GOM during the LIA and MWP? The major findings include: (1) The magnitude of temperature variability in the GOM over the past millennium is much larger than that estimated from Northern Hemisphere temperature reconstructions. The MWP (1400-900 yrs BP) was characterized by SSTs in the GOM that were similar to the modern SST, while the LIA (400-150 yrs BP) was marked by a series of multidecadal intervals that were 2-2.5°C cooler than modern. (2) This LIA cooling was replicated in the Mg/Ca-SST records from three different well-dated northern GOM basins (Pigmy, Garrison and Fisk Basins), as well as in two different geochemical proxies. (3) It is determined that foraminiferal test size has a significant effect on shell geochemistry. Using core-top calibration, discrepancies in the seasonal/depth habitats between different planktonic Foraminifera, and between Foraminifera and Crenarchaeota are inferred. Downcore differences are used to make inferences about changes in GOM mixed layer depth and seasonality over the past millennium.
Download or read book Geochemical Tracers of Holocene Environmental Change Along the East Antarctic Margin written by Natalie Romanoff and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aquatic Sciences and Fisheries Abstracts written by and published by . This book was released on 1991 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt:
