Jumbo Dome - Introduction

Jumbo Dome description and information

LOCATION

FACTS

Official Name:	Jumbo Dome
Type:	A large cylindrical plug of hornblende andesite
Most Recent Activity:
Seismically Monitored:	No
Elevation:	4491 ft (1369 m)
Latitude:	63.975° N
Longitude:	148.69444° W
Quadrangle:	Healy
CAVW Number:
Pronunciation:	Sound file
Nearby towns:	Ferry 9 mi (14 km) NW Healy 12 mi (19 km) SW Denali Borough 12 mi (19 km) SW McKinley Park 18 mi (29 km) SW Anchorage 194 mi (313 km) SW

DESCRIPTION

From Albanese (1980) ^[1]: "Jumbo Dome is a large cylindrical plug of hornblende andesite 1.6 km long, 1.3 km wide, and 500 m high which intrudes the Devonian Keevy Peak Formation basement and overlying Tertiary Suntrana Formation." Ar/Ar dating by Athey and others (2006) ^[2] yields an age for Jumbo Dome of 1.026 +/- 0.057 Ma.

REFERENCES CITED

^[1]

The geology of three extrusive bodies in the Central Alaska Range, 1980
Albanese, Mary, 1980, The geology of three extrusive bodies in the Central Alaska Range: University of Alaska Fairbanks unpublished M.S. thesis, 104 p.

^[2]

Bedrock geologic map of the Liberty Bell area, Fairbanks A-4 Quadrangle, Bonnifield mining district, Alaska, 2006
Athey, J.E., Newberry, R.J., Werdon, M.B., Freeman, L.K., Smith, R.L., and Szumigala, D.J., 2006, Bedrock geologic map of the Liberty Bell area, Fairbanks A-4 Quadrangle, Bonnifield mining district, Alaska: Alaska Division of Geological & Geophysical Surveys Report of Investigation 2006-2 v. 1.0.1, 98 p., 1 sheet, scale 1:50,000.