Unnamed (at Pilot Knob)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Fe
Ore minerals magnetite

Geographic location

Quadrangle map, 1:250,000-scale IL
Quadrangle map, 1:63,360-scale A-5
Latitude 59.1696
Longitude -154.6219
Nearby scientific data Find additional scientific data near this location
Location and accuracy The approximate location of this occurrence is on Pilot Knob in the NE1/4 NW1/4 sec. 2, T. 12 S., R. 32 W., Seward Meridian.

Geologic setting

Geologic description

A broad magnetic anomaly having a maximum relative intensity of 1,600 gammas is centered on Pilot Knob (Richter and Herreid, 1965, p. 15, figs. 7 and 8). The country rocks are hornfelsed volcanic rocks of the Jurassic Talkeetna Formation, underlain at shallow depth by the Cretaceous or Tertiary Pilot Knob granodiorite (Detterman and Reed, 1980). The granodiorite is partly altered to sericite, zoisite, and chlorite (Richter and Herreid, 1965, p. 7).
No magnetite or skarn is exposed at the site, but there could be shallow buried magnetite bodies at or near the contact between the granodiorite and the volcanic rocks. According to Richter and Herreid (1965), the contact of the granodiorite beneath Pilot Knob dips about 30 degrees. earby deposits of magnetite skarn in Talkeetna Formation volcanic rocks are at IL040 and IL042.
Geologic map unit (-154.624020749156, 59.1689103310696)

Production and reserves

Workings or exploration Exploration consists of geologic mapping and a ground-based magnetic survey (Richter and Herreid, 1965). There are no workings.
Indication of production None

References