Outcrop or artificial surface exposure, Pegmatite
| Geographic location |
-76.170833, 39.729167
76°
10'
15"
W,
39°
43'
45"
N
Lancaster county,
PA
Conowingo Dam
1:24,000 scale map quadrangle
Accurate to within 1 minute (~1 mile)
APPROX. 0.6 MILE NORTH OF PENNSYLVANIA-MARYLAND STATE LINE
|
|---|---|
| Source of sample | Outcrop or artificial surface exposure |
| Rock name | Pegmatite |
| Description | METASOMATIZED PEGMATITE (EXTENSIVE ALTERATION) |
| Laboratories | Berkeley Geochronology Center |
| Compiler name | Godoy, M.M. |
| Date compiled | 1979 03 |
| Precision of location | Accurate to within 1 minute (~1 mile) |
| Location comment | APPROX. 0.6 MILE NORTH OF PENNSYLVANIA-MARYLAND STATE LINE |
| Bibliographic reference | Lapham, D.M., and Bassett, W.A., 1964, K-Ar dating of rocks and tectonic events in the Piedmont of southeastern Pennsylvania: Geological Society of America Bulletin, v. 75, p. 661-668 |
| (click for info) | |
| Geologic map unit | -76.170833, 39.729167 |
| Nearby scientific data | Find additional scientific data near this location |
| Age estimate | 395 ± 20Ma initial age disturbed by later metamorphism
|
|---|---|
| Type of analysis | conventional K-Ar NO ANALYTICAL DATA GIVEN
|
| Rock or mineral analyzed | muscovite |
| Analytical details | |
| Lab sample ID | 16 |
| Decay constants | 4.83E-04, 0.585E-04 |