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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16795

Late Holocene estuarine-inner shelf interactions; is there evidence of an estuarine retreat path for Tampa Bay, Florida?

The purpose of this study was to determine if and how a large, modern estuarine system, situated in the middle of an ancient carbonate platform, has affected its adjacent inner shelf both in the past during the last, post-glacial sea-level rise and during the present. An additional purpose was to determine if and how this inner shelf seaward of a major estuary differed from the inner shelves locat
Authors
B.T. Donahue, A. C. Hine, S. Tebbens, S. D. Locker, D. C. Twichell

The west-central Florida inner shelf and coastal system: A geologic conceptual overview and introduction to the special issue

This paper provides an overview for this special publication on the geologic framework of the inner shelf and coastal zone of west-central Florida. This is a significant geologic setting in that it lies at the center of an ancient carbonate platform facing an enormous ramp that has exerted large-scale control on coastal geomorphology, the availability of sediments, and the level of wave energy. In
Authors
A. C. Hine, G. R. Brooks, R.A. Davis, D.S. Duncan, S. D. Locker, D. C. Twichell, G. Gelfenbaum

Sediment-starved sand ridges on a mixed carbonate/siliciclastic inner shelf off west-central Florida

High-resolution side-scan mosaics, sediment analyses, and physical process data have revealed that the mixed carbonate/siliciclastic, inner shelf of west-central Florida supports a highly complex field of active sand ridges mantled by a hierarchy of bedforms. The sand ridges, mostly oriented obliquely to the shoreline trend, extend from 2 km to over 25 km offshore. They show many similarities to t
Authors
S. E. Harrison, S. D. Locker, A. C. Hine, J.H. Edwards, D. F. Naar, D. C. Twichell, D. J. Mallinson

Determination of epsomite-hexahydrite equilibria by the humidity-buffer technique at 0.1 MPa with implications for phase equilibria in the system MgSO4-H2O

Epsomite (MgSO4·7H2O) and hexahydrite (MgSO4·6H2O) are common minerals found in marine evaporite deposits, in saline lakes as precipitates, in weathering zones of coal and metallic deposits, in some soils and their efflorescences, and possibly on the surface of Europa as evaporite deposits. Thermodynamic properties of these two minerals reported in the literature are in poor agreement. In this stu
Authors
I.-Ming Chou, Robert R. Seal

Stratigraphic framework of sediment-starved sand ridges on a mixed siliciclastic/carbonate inner shelf; west-central Florida

Seismic reflection profiles and vibracores have revealed that an inner shelf, sand-ridge field has developed over the past few thousand years situated on an elevated, broad bedrock terrace. This terrace extends seaward of a major headland associated with the modern barrier-island coastline of west-central Florida. The overall geologic setting is a low-energy, sediment-starved, mixed siliciclastic/
Authors
J.H. Edwards, S. E. Harrison, S. D. Locker, A. C. Hine, D. C. Twichell

Sand ridges off Sarasota, Florida: A complex facies boundary on a low-energy inner shelf environment

The innermost shelf off Sarasota, Florida was mapped using sidescan-sonar imagery, seismic-reflection profiles, surface sediment samples, and short cores to define the transition between an onshore siliciclastic sand province and an offshore carbonate province and to identify the processes controlling the distribution of these distinctive facies. The transition between these facies is abrupt and c
Authors
D. Twichell, Gillian L. Brooks, G. Gelfenbaum, V. Paskevich, Brian Donahue

A Visual Basic program to classify sediments based on gravel-sand-silt-clay ratios

Nomenclature describing size distributions is important to geologists because grain size is the most basic attribute of sediments. Traditionally, geologists have divided sediments into four size fractions that include gravel, sand, silt, and clay, and classified these sediments based on ratios of the various proportions of the fractions. Definitions of these fractions have long been standardized t
Authors
L. J. Poppe, A.H. Eliason, M. E. Hastings

Variation in habitat use by juvenile Acadian redfish, Sebastes fasciatus

A basic paradigm in behavioral ecology is that organisms expand their distribution as preferred sites become saturated with individuals that reduce the availability of resources (e.g., shelter, prey) on a per capita basis. Previous fish community studies at Stellwagen Bank National Marine Sanctuary have shown that juvenile Acadian redfish Sebastes fasciatus (20 cm TL) also occurred in dense cerian
Authors
P.J. Auster, J. Lindholm, P. C. Valentine

Critical pressure and multiphase flow in Blake Ridge gas hydrates

We use core porosity, consolidation experiments, pressure core sampler data, and capillary pressure measurements to predict water pressures that are 70% of the lithostatic stress, and gas pressures that equal the lithostatic stress beneath the methane hydrate layer at Ocean Drilling Program Site 997, Blake Ridge, offshore North Carolina. A 29-m-thick interconnected free-gas column is trapped benea
Authors
P.B. Flemings, Xiuying Liu, W.J. Winters

Mineral resource of the month: silicon

In the industrialized world, silicon is as ubiquitous in the objects people use every day as it is in nature. The second most abundant element in Earth’s crust and more than 25 percent of the crust by weight, silicon is one of the most useful elements to humans.
Authors
Lisa A. Corathers

Mineral resource of the month: platinum-group metals

The precious metals commonly referred to as platinum-group metals (PGM) include iridium, osmium, palladium, platinum, rhodium and ruthenium. PGM are among the rarest of elements, and their market values — particularly for palladium, platinum and rhodium — are the highest of all precious metals.
Authors
Henry Hilliard

Responses of infaunal populations to benthoscape structure and the potential importance of transition zones

Relationships between population abundance and seafloor landscape, or benthoscape, structure were examined for 16 infaunal taxa in eastern Long Island Sound. Based on analyses of a side-scan sonar mosaic, the 19.4-km2 study area was comprised of six distinct large-scale (> km2) benthoscape elements, with varying levels of mesoscale (km2-m2) and small-scale (< m2) physical and biological habitat he
Authors
R.N. Zajac, R. S. Lewis, L. J. Poppe, D. C. Twichell, J. Vozarik, M. L. DiGiacomo-Cohen
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