Preliminary results of absolute and high-precision gravity measurements at the Nevada Test Site and vicinity, Nevada

Technical Report · Sat Dec 31 04:00:00 EST 1988

OSTI ID:60632

Zumberge, M A; Harris, R N; Oliver, H W; Sasagawa, G S; Ponce, D A

Absolute gravity measurements were made at 4 sites in southern Nevada using the absolute gravity free-fall apparatus. Three of the sites are located on the Nevada Test Site at Mercury, Yucca Pass, and in northern Jackass Flats. The fourth site is at Kyle Canyon ranger station near Charleston Park where observed gravity is 216.19 mGal lower than at Mercury. Although there is an uncertainty of about 0.02 mGal in the absolute measured values, their gravity differences are considered accurate to about 0.03 mGal. Therefore, the absolute measurements should provide local control for the calibration of gravity meters between Mercury and Kyle Canyon ranger station to about 1 to 2 parts in 10,000. The average gravity differences between Mercury and Kyle Canyon obtained using LaCoste and Romberg gravity meters is 216.13 mGal, 0.06 mGal lower, or 3 parts in 10,000 lower than using the absolute gravity meter. Because of the discrepancy between the comparison of the absolute and relative gravity meters, more absolute and relative gravity control in southern Nevada, as well as the Mt. Hamilton area where the LaCoste and Romberg instruments were calibrated, is needed. Multiple gravity meter ties were also made between each of the four absolute stations to nearby base stations located on bedrock. These stations were established to help monitor possible real changes in gravity at the absolute sites that could result from seasonal variations in the depth to the water table or other local mass changes. 8 refs., 16 figs., 7 tabs.

• Research Organization: Geological Survey, Menlo Park, CA (United States)
• DOE Contract Number: AI08-78ET44802
• OSTI ID: 60632
• Report Number(s): USGS-OFR--88-242; ON: DE89003459
• Country of Publication: United States
• Language: English

Related Subjects

56 BIOLOGY AND MEDICINE
APPLIED STUDIES
CALIBRATION
EVALUATION
GRAVITATION
HIGH-LEVEL RADIOACTIVE WASTES
MEASURING INSTRUMENTS
NEVADA
NEVADA TEST SITE
UNDERGROUND DISPOSAL
Yucca Mountain Project