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Henry Chiles Riggs

Publications and source records attributed to Henry Chiles Riggs.

3 recordsLinked to original sources
USGS1977

A brief investigation of the surface-water hydrology of Yemen Arab Republic

Yemen, near the southwest tip of the Arabian Peninsula, is a mountainous country bordered by a desert on the east and a coastal plain on the west. Rainfall is low and seasonal; consequently, most streams (wadis) are ephemeral. The natural flow regimens of many of the smaller wadis are modified by terracing for agriculture. The only streamflow data available in Yemen are short records on four large wadis. A brief field investigation and application of reconnaissance techniques are the bases for the largely qualitative description of the hydrology, and for the proposal to collect streamflow data needed for orderly development of the expanding economy. (Woodard-USGS)

Open-File Report↗
USGS1974

Proposed hydrologic analyses of streamflow for Brazil

The objective of my assignment was to recommend what hydrologic analyses might be made using the records of stream discharge soon to be available at the gaging stations in Brazil. To attain this objective I (1) examined the streamflow records in part of the Rio Jacui basin in the state of Rio Grande do Sul for quality, length of record, and density of areal coverage; (2) locked at the available topographic maps; (3) spent one day in the field visiting gaging stations and observing general hydrologic conditions and (4) examined an isohyetal map of Brazil. The assignment was accomplished May 6-24, 1974.

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