fossil Flashcards
uniformitarianism
the theory that changes in the earth’s crust during geological history have resulted from the action of continuous and uniform processes.
catastrophism
the theory that changes in the earth’s crust during geological history have resulted chiefly from sudden violent and unusual events.
paleontology
the scientific study of life in the geologic past, based on examination of fossilized remains of once living organisms, such as tracks, bones, teeth, plants, and shells.
relative dating
the process of determining if one rock or geologic event is older or younger than another, without knowing their specific ages
absolute dating
measure the physical properties of an object itself and use these measurements to calculate its age.
superposition
the ability of a quantum system to be in multiple states at the same time until it is measured
isotope
each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.
radioactive decay
the process in which a radioactive atom spontaneously gives off radiation in the form of energy or particles to reach a more stable state.
half-life
the time required for a quantity (of substance) to reduce to half of its initial value.
fossil
the preserved remains of plants and animals whose bodies were buried in sediments, such as sand and mud, under ancient seas, lakes and rivers
trace fossil
a fossil of a footprint, trail, burrow, or other trace of an animal rather than of the animal itself.
mold
A mold or mould is one of the structures certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites.
cast
part of California’s system of assessments called the California Assessment of Student Performance and Progress
unconformity
An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous
mass extinction
the big death
Jurassic period
The Jurassic is a geologic period and stratigraphic system that spanned from the end of the Triassic Period 201.3 million years ago to the beginning of the Cretaceous Period, approximately 145 Mya.
Cretaceous period
The Cretaceous is defined as the period between 145.5 and 65.5 million years ago,* the last period of the Mesozoic Era, following the Jurassic and ending with the extinction of the dinosaurs
Devonian period
The Devonian is a geologic period and system of the Paleozoic, spanning 60.3 million years from the end of the Silurian, 419.2 million years ago, to the beginning of the Carboniferous, 358.9 Mya. It is named after Devon, England, where rocks from this period were first studied
Quaternary period
the third and last of the three periods of the Cenozoic Era. You and I are living in this period, which began only 2.58 million years ago. This is less than 0.1% of all of geologic time! A thin layer of sediments deposited during the Quaternary covers much of the Earth’s land surface.
Permian period
The Permian is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period 298.9 million years ago, to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era.
