Geologic Time USGS General Information Product
Washington, D. C. , USGS, 1988. Paperback. Very Good. Item #30556
ISBN: 1288678711
Unmarked. ; Book Description; Spine has staples. Pages are clean and not marred by notes or folds. Covers are square with wear as noted. Ships Safe and Fast. The Earth is very old 4 1/2 billion years or more according to recent estimates. This vast span of time, called geologic time by earth scientists, is difficult to comprehend in the familiar time units of months and years, or even centuries. How then do scientists reckon geologic time, and why do they believe the Earth is so old? A great part of the secret of the Earth's age is locked up in its rocks, and our centuries-old search for the key led to the beginning and nourished the growth of geologic science. ; Color Photographs; 8vo 8" - 9" tall; 20 pages DB2.
Price: $7.77