Preliminary results of precise leveling and trilateration surveys in Yellowstone National Park, Wyoming, 1983-1984
Dzurisin DD and Yamashita KM. 1986. Preliminary results of precise leveling and trilateration surveys in Yellowstone National Park, Wyoming, 1983-1984. U.S. Geological Survey (USGS) Open-File Report. 86-265-A. Vancouver, WA
Level surveys in Yellowstone National Park in 1923 and 1975-1977 revealed that parts of Yellowstone caldera rose by more than 700 mm during that interval along an axis connecting the Mallard Lake and Sour Creek resurgent domes, at an average rate of 14 mm/yr. Our surveys in October 1983 and September 1984 show that uplift continued since the 1975-1977 survey at an average rate of 22 mm/yr (180 mm net); we estimate the maximum uplift near LeHardy Rapids since 1923 to be about 980 mm. Because it is not known when the uplift began, it is not yet clear whether the rate of uplift is currently increasing, decreasing, or staying roughly constant. The net volume change inside the caldera since 1923 is conservatively estimated to be 0.75 km3; the average rate of volume increase is thus about 0.012 km3/y r. A precise trilateration network consisting of 8 lines 11 to 30 km long spanning the northeast part of the caldera was established in September 1984 to monitor horizontal strain changes associated with the continuing uplift.
- Type
- Published Report
- Authors
- Dzurisin, D; Yamashita, Kenneth
- Date of Issue
- 1986
- Units
- HIST , YELL
- Keywords
- Caldera, ehistory, Elevations, Geology, History, JeHardy Rapids, Leveling survey, Mallard Lake, Sour Creek, Topography, trilateration, Uplift