Outcrop or artificial surface exposure, Granodiorite
Geographic location |
-116.694722, 40.308056
116°
41'
41"
W,
40°
18'
29"
N
Lander county,
NV
Crescent Valley
1:62,500 scale map quadrangle
Accurate to within 1 minute (~1 mile)
SHOSHONE RANGE
|
---|---|
Source of sample | Outcrop or artificial surface exposure |
Rock name | Granodiorite |
Description | PORPHYRITIC GRANODIORITE |
Laboratories | USGS Menlo Park |
Compiler name | Nichols, S.L. |
Date compiled | 1978 02 |
Precision of location | Accurate to within 1 minute (~1 mile) |
Location comment | SHOSHONE RANGE |
Bibliographic reference | McKee, E.H., and Silberman, M.L., 1970, Geochronology Of Tertiary Igneous Rocks In Central Nevada: Geological Society of America Bulletin, v. 81, p. 2317-2328. |
(click for info) | |
Geologic map unit | -116.694722, 40.308056 |
Nearby scientific data | Find additional scientific data near this location |
Age estimate | 38.11Ma age of intrusion
|
---|---|
Type of analysis | conventional K-Ar REPLICATE POTASSIUM ANALYSES
|
Rock or mineral analyzed | biotite |
Analytical details | |
Lab sample ID | 3 |
Decay constants | 4.72E-04, 0.585E-04, 1.19E-04* |
K2O concentration | 7.99 % |
Radiogenic 40Ar concentration | 4.43 |
Radiogenic Ar | 81 % |
Age estimate | 38.45Ma age of intrusion
|
Type of analysis | conventional K-Ar REPEAT AR ANALYSIS
|
Rock or mineral analyzed | biotite |
Analytical details | |
Lab sample ID | 3 |
Decay constants | 4.72E-04, 0.585E-04, 1.19E-04* |
K2O concentration | 7.99 % |
Radiogenic 40Ar concentration | 4.47 |
Radiogenic Ar | 83 % |
Age estimate | 38.92Ma age of intrusion
|
Type of analysis | conventional K-Ar POTASSIUM VALUE IS AVERAGE OF 8 ANALYSES
|
Rock or mineral analyzed | hornblende |
Analytical details | |
Lab sample ID | 3 |
Decay constants | 4.72E-04, 0.585E-04, 1.19E-04* |
K2O concentration | 1.077 % |
Radiogenic 40Ar concentration | 0.61 |
Radiogenic Ar | 71 % |