ANTH 021 Chapter Notes - Chapter 8: Half-Life, Fluorine, Cenozoic
Document Summary
This dude william smith figured out there were patterns of sediment everywhere = strata. Fossils provide us with direct evidence for past life forms and their evolutions. Strata = layers of rock, representing various periods of deposition. Study of fossils has 2 main components: time and environment. Wholly or partially transformed into rock through chemical replacement. Minerals gradually replaced with rock-forming minerals like iron and silica. Taphonomy: study of deposition of plant/animal remains and environmental conditions affecting their preservation what must and must not happen for something to be fossilized. Bones and teeth = most common sources. Very few end up as fossils because left out too long, would be eaten (scavengers, maggots) Remains must stay oxygen free (anoxic), limited bacteria, little decomposition activity. Acidic soils an also erode fossils though, and geologic activity too. Most commonly found in sedimentary rock (rock formed with deposition of sediment creates distinct layers (strata)
