Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Trace Elements Investigations”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 505 records · Page 28Linked to original sources
USGS1951

Reconnaissance of radioactive rocks of Maine

The state of Maine was traversed with car-mounted Geiger-Mueller equipment in the late summer of 1948 and the radioactivity of approximately 4,600 miles of road was logged. All samples were analyzed, both in the field by comparing the radioactivity of each sample to the radioactivity of a stranded measured with a simple scaling modification of a portable counter, and in the Geological Survey’s Trace Elements Section Washington Laboratory. Differences between both types of analyses were negligible. The maximum equivalent uranium content of the most radioactive rocks thus analyzed was 0.008 percent. A 1,400-square-mile abnormally radioactive province in southwestern Maine was outlined. The outcrop data obtained from car traversing are evaluated statistically. Cumulative frequency distribution curves are drawn to show the distribution of outcrops at various levels of radioactivity, and straight-line extensions are made to show to maximum probable grade for various rock types and areas in Maine. A maximum grade of 0.055 percent equivalent uranium is thus predicted for the entire state. This prediction necessarily is a broad generalization because large areas of Main are inaccessible for car traversing. A concept of evaluation of an area for possible mineral deposits is proposed on the basis of lithology, and observed and indicated ranges in grade.

Maine↗
USGS1951

Reconnaissance of radioactive rocks of Massachusetts

During the 1948 and 1949 field seasons radiometric car traverses were made along the numbered federal and state highways and along many unnumbered roads of Massachusetts. Near Worcester pegmatitic rocks are estimated to contain about 250 pounds of uranium and 8,500 pounds of thoria per foot of depth. Near Southbridge pegmatitic rocks are estimated to contain about 6,500 pounds of thoria per foot of depth. A central belt was estimated to contain about 0.003 percent equivalent uranium but less than 0.001 percent uranium in nearly all roadside materials. Several smaller localities of radioactivity similar to that of the central belt were found but none appear to be important economically. Massachusetts is not considered a favorable area for uranium deposits, although some low-grade deposits of thorium are present.

Massachusetts↗