solid rocks dated uranium to lead ratio gives 4.5 billion years

4.5 billion years ago

earth is molten
slowly cooling
water is forming

4.4 billion most of surface solid
proof... Zircon crystals in the very old rock contains water 

4.0 billion years ago

great rainstorm for million of years
where did water come from .... meterorites
proof ... meterorites contain 5% water

3.5 billion years ago

S. Africa some of oldest rocks.... pillow lava 3.5 billion, only forms underwater
1. Pillow only under water
2. Uranium dates to 3.5 billion

3.5 billion - 2.5 billion years ago

continents, the granite planet 
green oceans
water + basalt = granite
proof .. S. Africa granite, nucleus of continent 
basalt much denser than granite

dark green is the nucleus of the continents

2.5 billion years ago

everywhere continent shelves place for life to evolve into oxygen producers

stromatolites.  Blue green bacteria 
.. Proof, fossil records

not until 1950's did they figure out stromatolites are built from the bacteria that precipitate CO2 out of atmosphere. 

1.5 billion years ago

Proof... rust band when oxygen combined
oceans blue clear, blue planet
banded iron formations... source for iron mining

FRESH water fossils, plate techtonics

proof and mechanism 
WWII.. Subs mapped ocean floor, Atlantic and the mid atlantic rift

ICELAND... sits over this ridge where it comes to the surface.
 "fissure eruptions" 25 miles long show path of the ridge, 2.5 or 1 inch per year moving apart 

1.5 billion years ago 

RODINIA ... supercontinent caused by nucleus of various continents coming together

primitive life forms left fossil records

700 - 630 million years ago

... Rodinia cut off circulation of heated water and resulted in 

2nd  big extinction

650 million years ago 
ice sheet 1 mile thick

heat build up, volcanoes split supercontinent apart, 

630 million
CO2 released created green house effect

550 - 500 million years ago

separate continents, shallow seas, oxygen, primative goes to complex critters in seas

500 million 
CAMBRIAN explosion, more different kinds of things than before or since

Burgress Shale quarry in N. America fossils galore

high oxygen levels, lead to ozone which stopped UV light destroying life on continents.

400 300 million years ago

continents converge again, life on continents explode 
one big fresh water swamps
CARBONIFEROUS = huge trees, hot steamy jungle, huge dragon flies and insects, then reptiles

COAL IS FORMED NOW ... in fresh water swamps. 200 million years. oil is formed in salt water oceans

250 million years ago


mantle plume in Siberia when on for 1 million years SIBERIAN TRAPS 

Permo-triassic extinction event 
supercontinent, Pangea 

240 - 180 million years ago

oxygen and CO2 rise to new peaks, 
animals evolved... dinosaurs

180 million ...
continent PANGEA starts breaking apart


100 million years ago

continents in mostly current position

volcanoes bring up diamonds click on picture at right for animation of diamond formation

65 million years ago

230-65 dinos, 70% of life goes extinct

METEORITE hit in Mexico, yucatan 
proof.. Iridium all over earth at that boundary
iridium comes from meteors
on the other side of the earth, the INDIAN DECCAN TRAPS
volcanic eruptions... 


50 million years ago 

mammals take over, opossum was already there towards end of dinosaurs


2 million years ago

ancestors of modern humans spread out of Africa
glaciation and ice ages start
land bridge formed in Panama and stopped ocean currents and tipped into ice ages

10,000 years ago

last glacier
Cape Cod boulders
great lakes dug out

humans spread and prospered