Radiometric Dating Flashcards
Determines the sequence of events and their relative ages, but not their specific numerical age
Relative Dating
A method used for sequencing rock layers, fossils, and geologic events
Relative Dating
What are commonly used in Relative Dating?
Stratigraphy, Fossil Correlation, and the Principle of Cross-Cutting Relationships
Compares the abundance of a radioactive isotope to its decay products
Absolute Dating
Crucial for determining the age of archaeological and geological specimens
Absolute Dating
The two methods of Radiometric Dating
Relative Dating and Absolute Dating
What are the isotopes used in Absolute Dating?
C-14, K-40, U-238, U-235, Rb-87, and Th-232
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
C-14
5 730; organic remains up to 50 000 years; N-14
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
U-238
4.5 B; dating old rocks and minerals; Pb-206
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
K-40
1.25 B; dating igneous rocks, ancient geological events such as formation of mountain ranges and crystal evolution; Ar-40
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
Rb-87
49 B; extremely old, ancient rocks; Sr-87
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
Th-232
14 B; geological processes; Pb-208
The amount of time it takes for half of a sample of a substance to decay
Half-Life
HALF-LIFE IN YEARS; USAGE; ELEMENT IT DECAYS INTO
U-235
704 M; dating relatively young rocks and mineral up to 1 B; Pb-207
What is the age of the oldest fossil recorded?
3.5 B years old