206324403 | Cenozoic Era | "Age of Mammals" 65 mya - present; characterized by rapid radiation of mammals | |
206324404 | Paleozoic Era | 543 mya - 252 mya; rapid radiation of fish and amphibians | |
206324405 | Mesozoic Era | "Age of Reptiles" 252 mya - 65 mya; reptiles were dominant life form, ended after Cretaceous Period with mass extinction of dinosaurs | |
206324406 | geologic time scale | the division of Earth history into blocks of time--eons, eras, periods, and epochs. The time scale was created using relative dating principles. | |
206324407 | era | a geologic time unit; a subunit of eocs, and composed of multiple periods | |
206324408 | Precambrian Era | 4.6 billion to 544 million years ago; life developed as bacteria and softbodied, multicelled organisms. First mass extinction probably occurred near the end of the Precambrian | |
206324409 | core | the central part of the Earth; containing both the inner and the outer core | |
206324410 | mantle | thickest layer of the Earth; contains the plastic asthenosphere and a solid portion where convection currents are found | |
206324411 | crust | the thin and solid outermost layer of the Earth above the mantle | |
206324412 | lithosphere | the solid part of the earth consisting of the crust and outer mantle | |
206324413 | asthenosphere | The solid, plastic layer of the mantle beneath the lithosphere; made of mantle rock that flows very slowly, which allows tectonic plates to move on top of it | |
206324414 | igneous rock | rock formed by the solidification of molten magma | |
206324415 | sedimentary rock | A type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together | |
206324416 | metamorphic rock | rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions | |
206324417 | erosion | (geology) the mechanical process of wearing or grinding something down (as by particles washing over it) | |
206324418 | weathering | the decomposition and disintegration of rocks and minerals at the earth's surface by a mechanical and chemical process | |
206324419 | tectonic plate | a piece of the lithosphere that moves around on top of the asthenosphere | |
206324420 | continental drift | the gradual movement and formation of continents (as described by plate tectonics) | |
206324421 | seafloor spreading | the process that creates new sea floor as plates move away from each other at the mid-ocean ridges | |
206324422 | pangaea | (plate tectonics) a hypothetical continent including all the landmass of the earth prior to the Triassic period when it split into Laurasia and Gondwanaland | |
206324423 | plate boundary | the region where two tectonic plates are in contact | |
206324424 | convection current | a current caused by the rising of heated fluid and sinking of cooled fluid | |
206324425 | fault | (geology) a crack in the earth's crust resulting from the displacement of one side with respect to the other | |
206324426 | circum-pacific ring of fire | a zone of intense eartquake and valcaanic activity that that encircles the Pacific ocean basin; also calle the Circum-Pacific Belt. | |
206324427 | transform boundary | the boundary between tectonic plates that are sliding past each other horizontally | |
206324428 | convergent boundary | boundary between two colliding plates, often associated with mountain building ocean trenches and volcanic islands | |
206324429 | divergent boundary | boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them | |
206324430 | subduction zone | the region where an oceanic plate sinks down into the asthenosphere at a convergent boundary, usually between continental and oceanic plates |
APES Geology 1
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