GEOLOGY 1 Lecture Notes - Lecture 28: Meteoroid, Burnup, Acasta Gneiss
Document Summary
Oldest rock on earth, acasta gneiss in nwt is 4. 03* ga (but earth is tectonically active, rocks keep getting recycled) Oldest mineral on earth, zircon in australia is 4. 4 ga. *4. 28 ga in n. quebec; highly controversial. Meteors: glowing fragments of rock that are inside the earth"s atmosphere (shooting stars) Meteoroid: a meteorite before it hits the surface meteorite: piece of rock from outer space that hits the earth. Meteorite: piece of rock from outer space that hits the earth. Meteor showers: when earth"s orbit passes through a belt of cosmic dust and rock. Stones: resemble rocks found on earth; most common type of meteorite. Chondrite: most common, fe-, mg-, and ni-bearing minerals, magnetic composed of small round spheres (chondrules); 4. 6 ga. Achondrites: same composition, but lack the chondrules. Irons: composed of fe-ni alloy (high density); likely candidate that resembles. Stony irons: mix of stony silicate material and iron.
