Publications

Porosity is the state of being porous, as measured by the percentage of bulk volume of a rock or soil that is occupied by space, whether isolated or connected. In hydrocarbon-bearing limestone settings, subsurface porous strata containing the oil or gas usually underlie non-porous caprock through which hydrocarbons cannot pass. In settings, subsurface freshwater aquifers beneath caprock...

Every year, billions of tons of fine particles are eroded from the surface of the Sahara Desert and the Sahel of West Africa, lifted into the atmosphere by convective storms, and transported thousands of kilometers downwind. Most of the dust is carried west to the Americas and the Caribbean in the Saharan Air Layer (SAL). Dust air masses predominately impact northern South America during...

The U.S. Geological Survey established a sediment trap in the northern Gulf of Mexico to collect time-series data on the flux and assemblage composition of live planktic foraminifers. This report provides an update of the 2008 time-series data to include results from 2009. Ten species, or varieties, of planktic foraminifers constitute >90 percent of the assemblage: Globigerinoides ruber...

Alina Reef is one of several thousand patch reefs that lie across the shallow carbonate platform seaward of Hawk Channel off the northern Florida Keys. The site is near the northern latitudinal fringe of the late Holocene western Atlantic coral reef distribution (Figure 1). The area is covered by calcareous sand and discontinuous Thalassia testudinum seagrass meadows and is studded with...

No abstract available.

No abstract available.

The metabolism of Cayo Enrique Reef, Puerto Rico, was studied using in situ methods during March 2009. Benthic O2 fluxes were used to calculate net community production using both the boundary layer gradient and enclosure techniques. The boundary layer O2 gradient and the drag coefficients were used to calculate productivity ranging from −12.3 to 13.7 mmol O2 m−2 h−1. Productivity...

Tampa Bay, Florida, USA, is a shallow, subtropical estuary that experienced severe cultural eutrophication between the 1940s and 1980s, a period when the human population of its watershed quadrupled. In response, citizen action led to the formation of a public- and private-sector partnership (the Tampa Bay Estuary Program), which adopted a number of management objectives to support the...

This Digital Versatile Disc (DVD) publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, nor shall the act of distribution imply any such warranty. The U.S...

As a low-lying peninsula surrounded by water, Florida faces tough decisions about long-range planning and development strategies to address impacts of climate change. In 2007, the Intergovernmental Panel on Climate Change (IPCC) stated there is strong evidence that global average sea level will rise by ? to 2 feet in the next century due to continued thermal expansion and melting of ice...

Tropical small mountainous rivers deliver a poorly quantified, but potentially significant, amount of carbon to the world’s oceans. However, few historical records of land–ocean carbon transfer exist for any region on Earth. Corals have the potential to provide such records, because they draw on dissolved inorganic carbon (DIC) for calcification. In temperate systems, the stable- (δ13C)...

Three years of weekly- to biweekly-resolved sediment-trap data show that almost 90% of the total flux of tests of the planktic foraminifer Globorotalia truncatulinoides to sediments in the northern Gulf of Mexico occurs in January and February. Comparison of δ18O from tests of non-encrusted Gl. truncatulinoides in sediment-trap samples with calculated calcification depths indicates that...