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Garald G. Parker

Publications and source records attributed to Garald G. Parker.

6 recordsLinked to original sources
USGS1973

Tests of rhodamine WT dye for toxicity to oysters and fish

Because of the toxicity to oyster larvae and eggs of rhodamine B dye in concentrations greater than 1 mg/l in earlier tests, there was a concern that rhodamine WT, a similar tracer dye, would have a detrimental effect on marine life being developed under the aquaculture program of the Lummi Indian Tribe near Bellingham, Wash. Tests showed that 48-hour exposures at 24° C of 11,000 oyster eggs per liter and 6,000 12-day-old larvae per liter, in sea water with concentrations of rhodamine WT ranging from 1 μg/l to 10 mg/l, resulted in development of the eggs to normal straight-hinge larvae and no abnormalities in the larvae development. Tests made on the smolt of both silver salmon and Donaldson trout, with the fish held for 17.5 hours in a tankfull of sea water with a dye concentration of 10 mg/l at 22°C showed no mortalities or respiratory problems. With the concentration increased to 375 mg/l, and the time extended an additional 3.2 hours, still no mortalities or abnormalities were noted. The fish remained healthy in dye-free water when last checked a month after the test.

Journal of Research of the U.S. Geological Survey↗
USGS1964

Officer's cave, a pseudokarst feature in altered tuff and volcanic ash of the John Day formation in eastern Oregon

Officer 's Cave is the uppermost of four rapidly eroding cave levels constituting a cavern complex about 700 feet long developed chiefly in clay and silt. Its outer room is 35 feet by 43.5 feet by 100 feet and slopes about 45° east into the western end of a narrow linear hill called Officer 's Cave Ridge. Dry valleys, blind valleys, hanging valleys, sinkholes, pipes, caves, and natural bridges are abundant. These, together with subterranean drainage, give the area a karstlike development. For such terrains the term " pseudokarst " is applied. These pseudokarsts are the product of piping and are fairly widespread over the world's drylands.

Oregon↗
USGS1950

Effects of earthquakes, trains tides, winds, and atmospheric pressure changes on water in the geologic formations of southern Florida

Determination of such fundamental hydrologic factors as the coefficients of permeability, transmissibility, and storage; areas of recharge and discharge; direction of ground-water movement; the safe yield; and other pertinent, related factors are based in part upon water-level measurements in wells. But these water-level readings, if not properly understood or weighted, may be entirely misleading. This is because water levels are neither stationary nor steadily rising (with recharge) or falling (with discharge). Water levels fluctuate as a result of several factors other than those of changes in recharge or discharge, chief among which are: (1) tides; (2) atmospheric pressure; (3) winds; (4) earthquakes; and (5) passing trains. Characteristically, artesian aquifers respond to these forces in a manner different from that of nonartesian aquifers, but in some places local geologic conditions in a nonartesian aquifer may cause water-level fluctuations ordinarily found only in artesian wells. Among the unusual features observed is a 4.5-foot fluctuation of water level in a Miami well caused by earthquake waves originating 750 miles away in the Atlantic Ocean, off the coast of the Dominican Republic. Quakes from all over the world are responsible for water-level fluctuations in this and other wells in the Miami area.

Florida↗