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Albert C. Hine

Publications and source records attributed to Albert C. Hine.

12 recordsLinked to original sources
USGS2019

Recent outer-shelf foraminiferal assemblages on the Carnarvon Ramp and Northwestern Shelf of Western Australia

The carbonate sediments of the Western Australian shelf in the Indian Ocean host diverse assemblages of benthic foraminifera. Environments of the shelf are dominated by the southward-flowing Leeuwin Current, which impacts near-surface circulation and influences biogeographic ranges of Indo-Pacific warm-water foraminifera. Analyses of outer ramp to upper slope sediments (127–264 m water depth) at four different sites (some with replicates) revealed 185 benthic species. A shift from benthic to planktonic foraminifera was accompanied by the decrease of “larger” benthic foraminifera below the lowermost euphotic zone. Fisher α and proportions of buliminid and textularid taxa increased with water depth, as miliolids and rotalids decreased in proportion. Cluster analyses on the 125–250 μm and 250–850 μm size fractions revealed distinct assemblages, with the former distinguishing between deeper and shallower sites, and the latter distinguishing between the Carnarvon Ramp-site in the south and the three sites on the Northwestern Shelf (NWS). The assemblage shift with depth was likely caused by rapidly changing physical conditions in the upper thermocline. The assemblage differences between the NWS and the Carnarvon Ramp indicate limited horizontal transport and migration rates on the outer shelf below the influence of the Leeuwin Current. Similarity in bottom-water temperature at the studied sites indicates that water mass characteristics, biogeographic history or possibly diversity in benthic shelf habitats rather than temperature and depth are responsible for differences between the two regions.

Carnarvon Ramp, Northwestern Shelf↗
USGS2019

Distribution of modern salt-marsh Foraminifera from the eastern Mississippi Sound, U.S.A.

This study documented surface distributions of live and dead foraminiferal assemblages in the low-gradient tidal marshes of the barrier island and estuarine complex of the eastern Mississippi Sound (Grand Bay, Pascagoula River, Fowl River, Dauphin Island). A total of 71,833 specimens representing 38 species were identified from a gradient of different elevation zones across the study area. We identified five live assemblages and nine biofacies for the dead assemblages from estuarine, low marsh, middle marsh, high marsh, and upland transition environments. Although dissolution of calcareous tests was observed in the dead assemblages, characteristic species and abundance patterns dependent on elevation in the intertidal zone were similar between living assemblages and dead biofacies. The assemblages from the eastern Mississippi Sound estuaries were dominated by Ammonia tepida, Cribroelphidium poeyanum, C. excavatum, and Paratrochammina simplissima. The low marshes were dominated by Ammotium salsum, Ammobaculites exiguus, and Miliammina fusca. The dominant species in the middle marshes was Arenoparrella mexicana. The most abundant species in the high marshes was Entzia macrescens. The upland–marsh transition zones were dominated by Trochamminita irregularis and Pseudothurammina limnetis. Canonical correspondence analysis was applied to assess the relationship between a priori defined biofacies and measured environmental data (elevation, grain size, organic matter, and salinity) to test the hypothesis that distribution of foraminiferal assemblages is driven by elevation and hence flooding frequency. Salinity was the second most important explanatory variable of dead assemblages. Riverine freshwater from the Pascagoula River markedly influenced the live and dead assemblages in the Pascagoula River marsh, which was represented by low diversity and densities and dominance by Ammoastuta inepta. The relationship between the measured environmental variables and assemblage distributions can be used in future Mississippi Sound paleo-environmental studies.

Mississippi↗
USGS2018

Benthic foraminifera from the Carnarvon Ramp reveal variability in Leeuwin Current activity (Western Australia) since the Pliocene

Benthic foraminiferal assemblages from a ~300 m deep core from an outer carbonate-ramp site off Western Australia (International Ocean Discovery Program Core U1460A) were examined to reconstruct the paleoceanographic evolution of the Carnarvon Ramp and the warm surficial Leeuwin Current (LC) for the last 3.54 Ma. Of the identified 179 benthic foraminiferal species, occurrences of the 15 most abundant taxa were assessed using Q-mode Cluster Analysis and Non-Metric Dimensional Scaling. Diversity, equitability, planktonic/benthic index, microhabitat preference, and sedimentary parameters such as lithology and sponge spicule content were analyzed to gather information about past intermediate- and surface-water circulation. Relative abundances of infaunal and epifaunal species were applied to indicate changes in organic-matter supply and oxygenation at the sea floor. Influence of upwelling was recognized by a high infaunal species ratio, with dominance by Uvigerina peregrina , Lagena annellatrachia and Trifarina bradyi . Epifaunal species such as Hanzawaia nipponica and Hyalinea florenceae gradually became more abundant around 1.14 Ma, indicating increased ventilation and establishment of the paleo-LC. A more substantial change was initiated by 0.91 Ma as marked by key species Spirorutilus carinatus and Rotorbinella sp. , together with increased faunal diversity, benthic foraminiferal accumulation rates, and evidence for suspension feeding sponges. With the LC flow suppressing upwelling, and better ventilated waters entering the shelf, the environment favored epifaunal agglutinates, rotalids, and miliolids, while buliminids decreased. Under high-flow conditions of the LC, sponge spicules and skeletal carbonate production reached an optimum at ~0.6 Ma before returning to modern conditions. Supported by these observations, we propose the following paleoceanographic evolution of the Carnarvon Ramp: During the late Pliocene to mid Pleistocene (3.54–0.91 Ma) conditions of deep-water upwelling from the Western Australian Current and Indian Ocean Gyre indicate the absence of the capping LC on the outer carbonate ramp. A transitional phase started in the mid Pleistocene (1.14–0.61 Ma). The paleo-LC triggered gradual oxygenation at the sediment-water interface, which coincided with an increase in carbonate sedimentation rates, and waning sea-surface productivity. During a third phase, mid Pleistocene to present (0.91–0 Ma), the LC’s intensity and flow rates peaked at ~0.6 Ma. Benthic foraminiferal accumulation rates reached a high, then decreased to present-day rates. For short periods, sea-surface productivity was moderately enhanced, likely due to fluctuating LC persistence or landward shift during glacial maxima.

Western Australia↗
USGS2016

Geology and biology of the "Sticky Grounds," shelf-margin carbonate mounds, and mesophotic ecosystem in the eastern Gulf of Mexico

Shelf-margin carbonate mounds in water depths of 116–135 m in the eastern Gulf of Mexico along the central west Florida shelf were investigated using swath bathymetry, side-scan sonar, sub-bottom imaging, rock dredging, and submersible dives. These enigmatic structures, known to fisherman as the “Sticky Grounds”, trend along slope, are 5–15 m in relief with base diameters of 5–30 m, and suggest widespread potential for mesophotic reef habitat along the west Florida outer continental shelf. Possible origins are sea-level lowstand coral patch reefs, oyster reefs, or perhaps more recent post-lowstand biohermal development. Rock dredging recovered bioeroded carbonate-rock facies comprised of bored and cemented bioclastics. Rock sample components included calcified worm tubes, pelagic sediment, and oysters normally restricted to brackish nearshore areas. Several reef sites were surveyed at the Sticky Grounds during a cruise in August 2010 with the R/V Seward Johnson using the Johnson-Sea-Link II submersible to ground truth the swath-sonar maps and to quantify and characterize the benthic habitats, benthic macrofauna, fish populations, and coral/sponge cover. This study characterizes for the first time this mesophotic reef ecosystem and associated fish populations, and analyzes the interrelationships of the fish assemblages, benthic habitats and invertebrate biota. These highly eroded rock mounds provide extensive hard-bottom habitat for reef invertebrate species as well as essential fish habitat for reef fish and commercially/recreationally important fish species. The extent and significance of associated living resources with these bottom types is particularly important in light of the 2010 Deepwater Horizon oil spill in the northeastern Gulf and the proximity of the Loop Current. Mapping the distribution of these mesophotic-depth ecosystems is important for quantifying essential fish habitat and describing benthic resources. These activities can improve ecosystem management and planning of future oil and gas activities in this outer continental shelf region.

Continental Shelf Research↗
USGS2010

Pleistocene carbonate stratigraphy of South Florida: Evidence for high-frequency sea-level cyclicity

Pleistocene carbonates of south Florida and islands of the Florida Keys are currently divided into five marine sequences designated, from oldest to youngest, the Q1–Q5 units. The units include a mosaic of freshwater and shallow marine deposits that accumulated on the Florida platform during high sea-level stands. The units are separated by regional-scale subaerial-exposure surfaces that formed during glacioeustatic lowstands. Analyses of cores recovered at Grossman Ridge Rock Reef and Joe Ree Rock Reef in the Florida Everglades reveal additional subaerial-exposure surfaces that are used to delineate subdivisions within units Q1 (Q1a–Q1b), Q2 (Q2a–Q2d), and Q4 (Q4a–Q4b). Units Q1–Q5 preserve evidence of at least 10 separate sea-level highstands, rather than 5 as indicated by previous studies. Compilation of available uranium-series dates on corals recovered from the Florida Keys indicates that the Q4 unit accreted during sea-level maxima associated with marine oxygen-isotope Stage 9 (Q4a) and isotope Stage 7 (Q4b). The Q5 unit formed during isotope Stage 5. No reliable dates are available for units Q1–Q3. We infer that unit Q3 was formed during the extended sea-level highstand of isotope Stage 11 and that units Q2 and Q1 predate isotope Stage 11.

Florida↗
USGS2008

Coral reefs, present and past, on the west Florida shelf and platform margin: Chapter 4

This paper summarizes the geomorphic variability of these different reef types, their geologic setting, and the present coral-reef biological community. The paper is organized along a virtual depth transect by presenting different reef settings and types starting from the shallower mid-shelf or mid-ramp setting, moving to the shelf edge, and then to the deeper upper slope.

Florida↗
USGS2007

Spatial trends in marsh sediment deposition within a microtidal creek system, Waccasassa Bay, Florida

Marsh surface deposition, suspended sediment concentrations, tidal hydrodynamics, and marsh surface characteristics were measured within a tidal creek system of a west-central Florida, microtidal, open marine Juncus roemerianus marsh to examine the depositional relationship between a creek system and the surrounding marsh during nonstorm conditions. Results suggest that short-term marsh deposition is highly episodic with deposition showing an inverse relationship with marsh surface inundation. Deposition was greatest at marsh sites adjacent to secondary creek segments over all examined timescales. Variations in hydroperiod, time–velocity asymmetry, vegetation density, and sediment availability could not explain the observed differences in short-term deposition.

Florida↗
USGS2003

Development of small carbonate banks on the south Florida platform margin: Response to sea level and climate change

Geophysical and coring data from the Dry Tortugas, Tortugas Bank, and Riley&rsquo;s Hump on the southwest Florida margin reveal the stratigraphic framework and growth history of these carbonate banks. The Holocene reefs of the Dry Tortugas and Tortugas Bank are approximately 14 and 10 m thick, respectively, and are situated upon Pleistocene reefal edifices. Tortugas Bank consists of the oldest Holocene corals in the Florida Keys with earliest coral recruitment occurring at &sim;9.6 cal ka. Growth curves for the Tortugas Bank reveal slow growth (<1 mm/yr) until 6.2 cal ka, then a rapid increase to 3.4 mm/yr, until shallow reef demise at &sim;4.2 cal ka. Coral reef development at the Dry Tortugas began at &sim;6.4 cal ka. Aggradation at the Dry Tortugas was linear, and rapid (&sim;3.7 mm/yr) and kept pace with sea-level change. The increase in aggradation rate of Tortugas Bank at 6.2 cal ka is attributed to the growth of the Dry Tortugas reefs, which formed a barrier to inimical shelf water. Termination of shallow (<15 m below sea level) reef growth at Tortugas Bank at &sim;4.2 cal ka is attributed to paleoclimate change in the North American interior that increased precipitation and fluvial discharge. Reef growth rates and characteristics are related to the rate of sea-level rise relative to the position of the reef on the shelf margin, and are additionally modified by hydrographic conditions related to climate change.

Florida↗
USGS2003

Sediment dynamics of a sediment-starved, open-marine marsh embayment: Waccasassa Bay, Florida

Although the Big Bend region of Florida's Gulf of Mexico coast is considered sediment-starved, the open marine marshes that characterize the area are keeping pace with sea level rise. Waccasassa Bay, an embayment within this region, also contains unique subtidal mudbanks that thicken with increasing proximity to embayment head, while the remainder of the bayfloor is characterized by exposed carbonate bedrock or by a thin veneer of sediment. Hydro- dynamic data sets were collected to determine the primary sedimentary processes within Waccasassa Bay capable of creating such geomorphic features. Data suggest that the embayment is a flood-dominated system influenced primarily by semi-diurnal tides with flood-stage intensification towards the river-mouth. Subtidal mudbanks are believed to be the result of tidal time-velocity asymmetries and the convergence of sediment transport pathways. Flood dominance for potential bedload transport suggests a gradual infilling of the bay interior for the short time scale of this study. With no mechanism for seaward transport, Waccasassa Bay can be considered a sediment sink for the remainder of the Big Bend re

Florida↗
USGS2001

Surface-geophysical characterization of ground-water systems of the Caloosahatchee River basin, southern Florida

The Caloosahatchee River Basin, located in southwestern Florida, includes about 1,200 square miles of land. The Caloosahatchee River receives water from Lake Okeechobee, runoff from the watershed, and seepage from the underlying ground-water systems; the river loses water through drainage to the Gulf of Mexico and withdrawals for public-water supply and agricultural and natural needs. Water-use demands in the Caloosahatchee River Basin have increased dramatically, and the Caloosahatchee could be further stressed if river water is used to accommodate restoration of the Everglades. Water managers and planners need to know how much water will be used within the river basin and how much water is contributed by Lake Okeechobee, runoff, and ground water. In this study, marine seismic-reflection and ground-penetrating radar techniques were used as a means to evaluate the potential for flow between the river and ground-water systems. Seven test coreholes were drilled to calibrate lithostratigraphic units, their stratal geometries, and estimated hydraulic conductivities to surface-geophysical profiles. A continuous marine seismic-reflection survey was conducted over the entire length of the Caloosahatchee River and extending into San Carlos Bay. Lithostratigraphic units that intersect the river bottom and their characteristic stratal geometries were identified. Results show that subhorizontal reflections assigned to the Tamiami Formation intersect the river bottom between Moore Haven and about 9 miles westward. Oblique and sigmoidal progradational reflections assigned to the upper Peace River Formation probably crop out at the floor of the river in the Ortona area between the western side of Lake Hicpochee and La Belle. These reflections image a regional-scale progradational deltaic depositional system containing quartz sands with low to moderate estimated hydraulic conductivities. In an approximate 6-mile length of the river between La Belle and Franklin Lock, deeper karstic collapse structures are postulated. These structures influence the geometries of parallel reflections that intersect the river channel. Here, reflections assigned to the Buckingham Limestone Member of the Tamiami Formation (a confining unit) and reflections assigned to the clastic zone of the sandstone aquifer likely crop out at the river bottom. Beneath these shallow reflections, relatively higher amplitude parallel reflections of the carbonate zone of the sandstone aquifer are well displayed in the seismic-reflection profiles. In San Carlos Bay, oblique progradational reflections assigned to the upper Peace River Formation are shown beneath the bay. Almost everywhere beneath the river, a diffuse ground-water flow system is in contact with the channel bottom. Ground-penetrating radar profiles of an area about 2 miles north of the depositional axis of the deltaic depositional system in the Ortona area show that progradational clinoforms imaged on seismic reflection profiles in the Caloosahatchee River are present within about 17 feet of the ground surface. Ground-penetrating radar profiles show southward dipping, oblique progradational reflections assigned to the upper Peace River Formation that are terminated at their tops by a toplapping or erosional discontinuity. These clinoformal reflections image clean quartz sand that is probably characterized by moderate hydraulic conductivity. This sand could be mapped using ground-penetrating radar methods.

Water-Resources Investigations Report↗
USGS1992

Holocene coastal development on the Florida peninsula

The Florida peninsula contains five distinct coastal sections, each resulting from its own spectrum of coastal processes and sediment availability during a slowly rising, late Holocene sea level. The east coast barrier system is wave-dominated and has a large cuspate foreland (Cape Canaveral) near its middle. The Florida Keys and reef tract represent the only coastal carbonate system in the continental United States. An open-marine mangrove coast characterizes the low-energy, tide-dominated southwest part of the State. The central Gulf barrier system displays a mixed-energy morphology in a microtidal, low-energy setting. The open-coast marsh system of the Big Bend area that is north of the barrier system is also tide dominated, and is developed on a sediment-starved carbonate platform. The oldest preserved coastal Holocene section is the Florida Keys area where, at about 6 to 8 ka, sequences accumulated during the Holocene. Most of the remainder of the peninsular coast is characterized by terrigenous sequences less than 3 ka. The younger sequences accumulated almost exclusively from reworking of older strata without benefit of additional sediment supply from land.

Florida↗