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dating

(Encyclopedia)dating, the determination of the age of an object, of a natural phenomenon, or of a series of events. There are two basic types of dating methods, relative and absolute. In relative dating, the tempor...

geologic dating

(Encyclopedia)geologic dating: see dating.

radioactive dating

(Encyclopedia)radioactive dating: see dating.

dendrochronology

(Encyclopedia)dendrochronology: see dating.

apatite

(Encyclopedia)apatite ăpˈətīt [key], mineral, a phosphate of calcium containing chlorine or fluorine, or both, that is transparent to opaque in shades of green, brown, yellow, white, red, and purple. Apatite is...

Libby, Willard Frank

(Encyclopedia)Libby, Willard Frank, 1908–80, American chemist, b. Grand Valley, Colo., grad. Univ. of California (B.S., 1931; Ph.D., 1933). He taught (1933–45) at the Univ. of California and was a chemist (1941...

stratigraphy

(Encyclopedia)stratigraphy, branch of geology specifically concerned with the arrangement of layered rocks (see stratification). Stratigraphy is based on the law of superposition, which states that in a normal sequ...

Proverbs

(Encyclopedia)Proverbs, book of the Bible. It is a collection of sayings, many of them moral maxims, in no special order. The teaching is of a practical nature; it does not dwell on the salvation-historical traditi...

Clacton-on-Sea

(Encyclopedia)Clacton-on-Sea, town, Essex, E central England. It is a seaside resort situated on high cliffs. The Norman Church of St. John was restored there in 1865...

Roscommon, town, Republic of Ireland

(Encyclopedia)Roscommon, town (1991 pop. 3,427), county seat of Roscommon, central Republic of Ireland. Noted for its Dominican priory and the remains of a castle, both dating from the 13th cent., Roscommon is a to...