Paleontology Flashcards
Scientific study of fossils.
Paleontology
How do fossils form?
- possession of hard parts like exoskeleton, bones, nails
and tooth etc. - Rapid Burial.
- availability of finer rather than coarser sediments and
undisturbed conditions of sedimentation for a longer
period. - presence of highly mineralized ground water.
- calm waters, little oxygen. (Anoxic Environment)
the remains or traces of prehistoric organisms preserved in rocks, most common in sedimentary rocks, but they may also be found in volcanic ash and volcanic mudflows.
Fossils
What should be the age of the specimen to be considered a fossil?
10,000 years old
Three uses of fossils.
- determine the relative ages of strata
- for determining environments of
deposition - constitute some of the evidence for the theory of evolution
2 types of fossils.
Body Fossils and Trace Fossils
Body fossils include?
Skeletal parts, shells, bones and teeth
Trace fossils include?
Any indication of organic activity; Tracks, Trails, Burrows, and Nests, Feces (Coprolite)
Type of fossil preservation where;
Original composition and structure preserved.
Body Fossils-Unaltered Remains
Four methods where fossils can be preserved unaltered.
Freezing, Mummification, Preservation in Amber, and Preservation in Tar
Type of fossil preservation where:
Change in composition and/or structure of original material.
Body Fossils-Altered Remains
Four methods in which fossils are preseved by alterations to its remains.
Permineralization, Recrystallization, Replacement, Carbonization
Large Ice Age mammals frozen in sediment.
Freezing
Air drying and shriveling of soft tissues.
Mummification
Leaves, insects, and small reptiles trapped and preserved in hardened tree resin.
Preservation in Amber
Bones, insects, preserved in asphalt-like substance at oil seeps.
Preservation in Tar
Addition of minerals to pores and cavities in shells and bones.
Permineralization
One chemical compound replaces another—for example, pyrite (FeS2) replaces calcium carbonate (CaCO3) of shells.
Replacement
Volatile elements lost from organic matter leaving a carbon film; most common on leaves and insects.
Carbonization
A cavity with the shape of a bone or shell.
Mold
A mold filled by minerals or sediment.
Cast
Name of the 40,000 year old frozen Wooly Mammoth (30-35 days old), and was found on Yamal Peninsula in Russia.
Also regarded as the best preserved mammoth fossil in the world.
Lyuba
Name of the 40,000 year old frozen mammoth (7-8 months old), that was found in Northeastern Siberia
Dima
If an animal dies in a dry, protected location, like an arid cave, its remains can dry out, or desiccate.
Mummification (Drying or Dessication)
Name of the species of the tiny dinosaur nestled inside a 99 million-year-old amber, that was discovered in 2016.
Coelorosaurs
_____ _____ or more accurately an asphalt pit or asphalt lake, is the result of a type of Petroleum seep where subterranean bitumen leaks to the surface, creating a large area of natural asphalt. This happens because, after the material reaches the surface, its lighter components vaporize, leaving only the thick asphalt.
Tar Pit
A tar pit provides what kind of condition that favors fossilization?
Anoxic Conditions
is the process of turning living organic material into stone. This process takes place when the molecules in an organism are replaced with the molecules of a mineral.
Petrification
Happens when the pores of the plant materials, bones, and shells are impregnated by mineral matter from the ground, lakes, or ocean. In some cases, the wood fibers and cellulose dissolve and some minerals replace them. Sometimes the mineral substance of the fossils will completely dissolve and some other minerals replace them. The common minerals that form this kind of fossils are calcite, iron, and silica.
Permineralization
A process when water dissolves the original hard parts and replaces them with mineral matter. Calcite, silica, pyrite and hematite.
Replacement
A process by which the more volatile substances of plants and animals decay, but leave behind the carbon. Crumbly woods of lignite deposits are one example of ____________. At its extreme, ____________ reduces plants and animals to shiny black or brown film.
Carbonization
An organism will lie in sediment until the surrounding sediment becomes firm. Later the organism dissolves away.
Mold and Cast
The inside surface of the mold is referred to as
the ________ ______.
Internal Mold
The _______ ________ forms when sand or clay fills such things as empty shells of snails and clams, which are common.
Internal Cast
If the cavity is filled with grains of sand or clay, duplicating the original inner surface of the organism, this is referred to as a ______.
Cast
These are not actual remains but an indication of organic activity such as tracks, trails, burrows, and nests.
Trace Fossils or Ichnofossil
Type of trace fossil formed in soft sediment.
Burrows
Type of trace fossils made by organisms into hard substrate.
Borings
Resting traces
Cubichnia
Dwelling, Structures, and Burrows
Domichnia
Crawling tracks and trails.
Repichnia
Grazing traces.
Passichnia
Feeding traces.
Fodinichnia
A well-known Tar Pit
La Brea Tar Pits, LA California
Stomach Stones
Gastroliths
Term for Land Reptiles
Dinosaurs
Term for Flying Reptiles
Terrosaurs
Change in the crystal structure-for example, aragonite in shells recrystallizes as calcite.
Recrystallization
Other term for Trace Fossils.
Ichnofossils
The trace fossil known as a _______ is fossilized feces that may provide information about the diet and size of Trace Fossils or Ichnofossils the animal that produced it.
Coprolite
