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R.H. Meade

Publications and source records attributed to R.H. Meade.

34 records · Page 2Linked to original sources
USGS1983

Data from sediment studies of the Rio Orinoco, Venezuela, August 15-25, 1982

Water and suspended-sediment discharges were measured and bed-material samples were collected during August, 1982, at 9 cross sections along a 800-kilometer reach of the Rio Orinoco. Flows varied from approximately 31,000 to 72,000 cubic meters per second, and sediment discharge varied from approximately 1,600 to 8,000 kilograms per second. The bed material is mostly fine to medium sand and almost one-third of the suspended sediment is sand.

Open-File Report↗
USGS1982

Sources, sinks and storage of river sediments in the Atlantic drainage of the United States

The history of sediment and its movement in the Atlantic drainage demonstrate some of the difficulties of modeling sediment on a river-basin scale. Soil erosion was accelerated by a factor of at least 10 when European settlers cleared forests and planted crops. Although increasing soil-conservation practice and decreasing crop farming have since reduced the rates of erosion, large quantities of eroded material are still stored on hillslopes and in stream valleys where they continue to augment the sediment loads of the rivers. The sediment from this episode of erosion that is largely past can be expected to emerge from storage for many decades and perhaps even several centuries to come. The reservoirs that have been built on many of the major rivers trap significant portions of the moving sediment which, in some places, may be remobilized by large floods. Essentially all the river sediment that reaches the Atlantic coastal zone is trapped in estuaries and coastal marshlands. Probably less than 5% is deposited on the floor of the continental shelf or the deep sea.

Journal of Geology↗
USGS1982

Field data describing the movement and storage of sediment in the East Fork River, Wyoming; Part III, river hydraulics and sediment transport, 1980

Frequent measurements of river stage, water discharge, sediment-transport rate and particle-size gradation, and river slope were made at 44 cross sections along a 1.83-kilometer reach of East Fork River, Wyoming, during the spring 1980 snowmelt runoff. Data are tabulated and explanatory text facilitates its use for description of river hydraulics and sediment transport. (USGS)

Open-File Report↗
USGS1980

Size distribution of Amazon River bed sediment

The first recorded observations of bed material of the Amazon River were made in 1843 by Lt William Lewis Herndon of the US Navy, when he travelled the river from its headwaters to its mouth, sounding its depths, and noting the nature of particles caught in a heavy grease smeared to the bottom of his sounding weight1. He reported the bed material of the river to be mostly sand and fine gravel. Oltman and Ames took samples at a few locations in 1963 and 1964, and reported the bed material at O??bidos, Brazil, to be fine sands, with median diameters ranging from 0.15 to 0.25 mm (ref. 2). We present here a summary of particle-size analyses of samples of streambed material collected from the Amazon River and its major tributaries along a reach of the river from Iquitos in Peru, ???3,500 km above Macapa?? Brazil, to a point 220 km above Macapa??3. ?? 1980 Nature Publishing Group.

Nature↗
USGS1979

Particle size of sediments collected from the bed of the Amazon River and its tributaries in May and June 1977

One-hundred-eight samples of bed material were collected from the Amazon River and its major tributaries between Belem, Brazil , and Iquitos, Peru. Samples were taken with a standard BM-54 sampler or with pipe dredges from May 18 to June 5, 1977. Most of the samples have median diameters in the size range of fine to medium sand and contain small percentages of fine gravel. Complete size distributions are tabulated. (Woodard-USGS)

Open-File Report↗
USGS1977

Particle size of sediments collected from the bed of the Amazon River and its tributaries in June and July 1976

Sixty-five samples of bed material were collected from the Amazon River and its major tributaries between Belem, Brazil, and Iquitos, Peru. Samples were taken with a standard BM-54 sampler, a pipe dredge, or a Helley-Smith bedload sampler. Most of the samples have median diameters in the size range of fine to medium sand and contain small percentages of fine gravel. Complete size distributions are tabulated.

Open-File Report↗
USGS1971

Sea level as affected by river runoff, eastern United States

Variations in annual river inflow account for 7 to 21 percent of the total variation in average annual sea level along the Atlantic and Gulf of Mexico coasts of the United States. This compares with 29 to 68 percent of the total variation that can be attributed to the secular rise of sea level, and with 10 to 50 percent of the variation that cannot be attributed to either the river inflow or the secular rise.

eastern United States↗
USGS1970

Suspended matter in surface waters of the Atlantic continental margin from Cape Cod to the Florida Keys

Appreciable amounts of suspended matter (> 1.0 milligram per liter) in surface waters are restricted to within a few kilometers of the Atlantic coast. Particles that escape estuaries or are discharged by rivers into the shelf region tend to travel longshoreward rather than seaward. Suspended matter farther offshore, chiefly amorphous organic particles, totals 0.1 milligram per liter or less. Soot, fly ash, processed cellulose, and other pollutants are widespread.

Atlantic Coast, Cape Cod to the Florida Keys↗