History Of Earth Flashcards
Geological timescale
division of Earth’s history into units like eon, era, period, and epoch.
Principle of superposition
basic principles of relative dating. It states that any sedimentary bed in a sequence that is younger than the layers below it and the layers above it.
Principle of cross cutting relationships
dike that intrudes existing rock layers must be younger than the rock layers. A fault that cuts through an existing dike and the older rock layers.
Principle of lateral continuity
Sedimentary beds that end must have been cut off either due to pinching or by some event that post dates their deposition.
Earthquake
plates that slide past one another causing the ground to vibrate. These vibrations are known as earthquakes. Earthquakes can be destructive and can cause buildings to collapse.
Volcano
air rushes out under pressure. When magma beneath Earth’s surface is forced up because of pressure it flows out to Earth’s surface through openings volcanoes.
Meteor
fast streak of light that quickly disappears
Landslide
occurs on a slope of rain or disturbance such as an earthquake. Removal of a slope or can increase the likelihood of a landslide.
Plate motion
a number of tectonic plates that move to each other
Pangea
supercontinent formed in the Paleozoic era of Earth’s history.
Continental drift
Earths surface is made up of plates. Deep beneath Earth the mantle is hot and semi solid.
Alfred Wegner
German polar researcher
Relative age
an object is an indication of when it formed relative to when other objects formed.
Fossil
fossils are created when a plant or animal dies and is buried beneath mud or sand.
Plate tectonics theory
plates move gradually in relation to each other.
