Chapter 1 - Time and Fossils Flashcards
age of a rock in years, determined by radioactive dating
Absolute Age
direct evidence of ancient life as represented by a former part of that organism
Body Fossil
any indirect evidence of the existence of former life; commonly indicative of animal activity
Trace Fossil
study of ancient life on Earth
Paleontology
isotope that is radioactive and naturally decays to other elements through the loss of protons, neurons and electrons
Parent Isotope
isotope that is the final, stable decay product from the radioactive parent isotope
Daughter Isotope
amount of time necessary for a naturally occurring radioactive element to decay so that only half of the parent atoms remain
Half-life
one of two or more forms of an element having the same atomic number, but differing in atomic weight
Isotope
sum of the number of protons and neutrons in the nucleus of an atom (different isotopes of the same element have different mass numbers)
Mass Number
number of protons in the nucleus of an atom
Atomic Number
positively charged particle in the nucleus of an atom
Proton
one of the building blocks of atomic nuclei, lacks an electrical charge
Neutron
subatomic particle with a negative charge
Electron
stratigraphic concept proposed by Nicholas Steno stating that sedimentary strata continue for long distances geographically
Principle of Lateral Continuity
stratigraphic concept proposed by Nicholas Steno stating that sedimentary strata were deposited in horizontal layers
Principle of Original Horizontality
stratigraphic concept proposed by Nicholas Steno stating that in an undisturbed sequence of sedimentary strata, the oldest strata are at the bottom and the youngest strata are at the top
Principle of Superposition
rock time; Earth history prior to the beginning of the Paleozoic Era
From approximately 4.6 bya to 534 mya
Precambrian
oldest era of the Phanerozoic, younger than the Precambrian and older than the Mesozoic; from 543 bya to 245 mya
Paleozoic
era of geological time from 245 mya to 645 mya; the age of dinosaurs and ammonoids - “middle life”
Mesozoic
youngest era of geological time, from 65 mya to the present - “young life”
Cenozoic
a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena
Theory
an assumption or concession made for the sake of argument
Hypothesis
principles and procedures for the systematic pursuit of knowledge involving the recognition and formulation of a problem, the collection of data through observation and experiment, and the formulation and testing of hypotheses
Scientific Method
