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Research about Rainier Mesa

Source-linked reports with geographic coverage including Rainier Mesa.

5 recordsLinked to original sources

A process to estimate net infiltration using a site-scale water-budget approach, Rainier Mesa, Nevada National Security Site, Nevada, 2002–05

This report documents a process used to estimate net infiltration from precipitation, evapotranspiration (ET), and soil data acquired at two sites on Rainier Mesa. Rainier Mesa is a groundwater recharge area within the Nevada National Security Site where recharged water flows through bedrock fractures to a deep (450 meters) water table. The U.S. Geological Survey operated two ET stations on Rainier Mesa from 2002 to 2005 at sites characterized by pinyon-juniper and scrub-brush vegetative cover. Precipitation and ET data were corrected to remove measurement biases and gap-filled to develop continuous datasets. Net infiltration (percolation below the root zone) and changes in root-zone water storage were estimated using a monthly water-balance model. Site-scale water-budget results indicate that the heavily-fractured welded-tuff bedrock underlying thin (<40 centimeters) topsoil is a critical water source for vegetation during dry periods. Annual precipitation during the study period ranged from fourth lowest (182 millimeters [mm]) to second highest (708 mm) on record (record = 55 years). Annual ET exceeded precipitation during dry years, indicating that the fractured-bedrock reservoir capacity is sufficient to meet atmospheric-evaporative demands and to sustain vegetation through extended dry periods. Net infiltration (82 mm) was simulated during the wet year after the reservoir was rapidly filled to capacity. These results support previous conclusions that preferential fracture flow was induced, resulting in an episodic recharge pulse that was detected in nearby monitoring wells. The occurrence of net infiltration only during the wet year is consistent with detections of water-level rises in nearby monitoring wells that occur only following wet years.

Nevada↗

Lithologic log and drilling information for the Marble exploration hole 3, U15 area, Nevada Test Site, Nye County, Nevada

The Marble exploration hole 3 is in the northern part of the Tippipah Spring NE 7-1/2 minute quadrangle at the north end of Yucca Valley (fig.1). The collar elevation of the hole is about 5,316 feet and has the approximate Nevada State coordinates of N. 903,093 and E. 674,870. The hole was drilled to determine the physical and chemical properties of the marble within a radius of 200 feet of a point 950 feet below the surface. The exploration hole is 978 feet deep and was drilled from June 12 to July 8, 1959, by Minerals Engineering Co. of Grand Junction, Colorado, using conventional NX coring equiipment and a Portadrill 2,500 drill rig. Water-base bentonitic mud was used as the drilling fluid in the upper part of the hole. Clear water was used after circulation became unrestorable below 200 feet. The hole was cased from surface to 20 feet. The drilling rate during coring ranged from 2.0 to 19.3 minutes per foot and averaged 4.6 minutes per foot (table 1). The core recovered was excellent in quality and quantity. The average core recovery is 92.7 percent (table 2).

Nevada↗

Geological investigations in the U12b.03 and U12b.04 tunnels, Nevada Test Site

The papers comprising the various parts of this report contain preliminary results of the U. S. Geological Survey investigations in the U12b.03 and U12b.04 tunnels at the Nevada Test Site, Nye County, Nevada (fig. 1). The geologic studies were undertaken to define the structural, chemical, mineralogic, and some of the physical properties of the tuffaceous rocks that enclose the explosion chambers at the end of each tunnel. The U12b.03 and .04 tunnels are part of the U12b (Rainier) tunnel complex that was driven northwestward from the steep east slope of Rainier Mesa (a prominent topographic feature in the northwest part of the Test Site (fig . 2)). The U12b.03 tunnel trends north from a point about 980 feet from the portal of the U12b tunnel (fig. 3). The U12b.03 tunnel consists of 620 feet of tunnel, two alcoves, and a shot chamber. The tunnel is irregular, ranging from 6 to 10 feet in width, and 6 to 9 feet in height. The shot chamber at the north end of the tunnel is 22 feet on each sidee The vertical and minimum cover over the shot chamber are 610 and 510 feet, respectively.

Nevada↗

Geological Survey investigations in the U12e.05 tunnel, Nevada Test Site

The papers comprising the various parts of this report contain the preliminary results of the U. S. Geological Survey investigations in the U12e.05 tunnel at the Atomic Energy Commission's Nevada Test Site, Nye County & Nevada (fig. 1). Reports on electrical resistivity, natural radioactivity, and heat required to raise the rocks to 100&deg;C will be issued later. A preliminary report on the geologic effects of the Blanca event is being prepared. The U12e.05 tunnel, one of two laterals from the main U12e tunnel, trends west and connects with the main tunnel about U960 feet from the portal (fig. 2). The U12e.05 tunnel was driven for the nuclear test, code name Blanca, which took place on October 30, 1958. Before the explosion, the tunnel was 8 feet high and 8 to 9 feet wide and consisted of 990 feet of workings, a shot chamber, and an alcove (fig. 2). The original shot chamber, at the west end of the tunnel, was 19 feet long, 10 feet wide, and 15 feet high. The vertical and minimum cover over the original shot chamber are 1,150 and 950 feet, respectively. After detonation of the nuclear device in the test, code named Logan, in the U12e.02 tunnel on October 15, 1958, the U12e.05 tunnel, locally, was damaged severely.

Nevada↗

Geological Survey investigations in the U12b.01 tunnel, Nevada Test Site

The U12b.01 tunnel is part of the U12b (Rainier) tunnel system driven northwestward from the east slope of Rainier Mesa (figs. 1 and 2). Geologic and geophysical studies in this tunnel were conducted by the U.S. Geological Survey on behalf of the Albuquerque Operations Office of the Atomic Energy Commission. This report includes a brief description of the stratigraphy and structure, and data on petrology, mineralogy, and chemical and physical properties of the rocks that are exposed in the tunnel. The U12b.01 tunnel trends N. 10&deg; W., and connects with the Ul2b tunnel at about 500 feet from the portal (fig. 2). The U12b,01 tunnel is about 250 feet long and contains an alcove 40 feet long and 20 feet wide, and a shot chamber 17 by 20 feet. The tunnel is irregular and ranges from 6 to 15 feet in width and averages 7 feet in height. Much of the tunnel has been supported using 6-foot steel sets and wood planks for lagging Vertical and minimum cover over the shot chamber at west end of the tunnel are approximately the same, about 295 feet.

Nevada↗