early Geologists, history's mysteries, time, and geology
Mythology
earth is 4.54 billion yrs old
evidence fossils were prized by Neanderthals' 30,000 yr/ago for magical powers
greeks first to try explain fossils
neptunism
Abraham gottlob werner (1749-1817)
naturalist at his time believed ALL layered rock were deposited by water
plutonism
some people were convinced igneous rocks were once molten lava
James Hutton (father of geology)(1726-1797)
Uniformitarianism
observation of earths processes and result apply to the past
James Hutton and Charles Lyell formalized the concept
Hutton's idea did not have major support until Lyell's work
actualism
geologist moved away from uniformitarianism
both sudden and gradual changes are important
emphasized gradual change and would exclude sudden change
charles lyell
published principles of geology(1830)
championed for uniformity processes in frequency and intensity
described geologic features cutting across rock is younger than rock itself
nicholas stone
father of stratigraphy
fossils formed at same time as rock
recognized not all rock layers had formed at same time
william smith
english engineer
fossils occur in predictable vertical relation to another
created first geologic map based largely in part on fossils
geologic eons
hadean 4.6-4.0 GA
Archean 4.0-2.5 GA
Proterozoic 2.5-0.54 Ga
phanerozoic 0.54 to present
mesozoic 252-66ma
Paleozoic 541-252 ma
cenozoic 66ma-prsent
Krakatoa
Aug 1883
caused red sunsets in europe
heard 3000 miles away
cooled global climate .5C for several years
santorini/thera 1645-1500BC
Africa/Eurasians plate convergence
between greece and crete
3x-4x Krakatoa
east africa rift 3.5Ma
wet volcanic ash preserved two Australopithecus like lucy
walking side by side and upright
tracks showed bipedalism before the advent of toolmaking