Transcript Slide 1
Water’s Beginnings ‘The seeds of everything have a moist nature”. (Circa 600 B.C.) Thales of Meletus “the father of science” 7 sages of Greece Solon of Athens - "Nothing in excess" Chilon of Sparta - "Know thyself" Thales of Miletus - "To bring surety brings ruin" Bias of Priene - "Too many workers spoil the work" Cleobulus of Lindos - "Moderation is the chief good" Pittacus of Mitylene - "Know thine opportunity" Periander of Corinth - "Forethought in all things" spherical Earth moon reflected light from the sun Solar Eclipse: 585 B.C.. water is the origin and essence of all things Essence of all things? Water in the Solar System Ice core Ice and liquid clouds Radar ice ice Oceans Vapor Temp. and Po Ice Ice and liquid clouds. How large is the earth? Radius: 3986 mi (4000 mi) Diameter: 7973 mi (8000 mi) Circumference: 25,048 mi (25,000 mi) How much water is there? 400 billion billion gallons 326 million mi3 Total Earth Water = 326 million mi3 688 miles 1 cubic mile 93 million miles 326 million mi3 0.12% of the earth’s volume What percentage is readily available fresh water? When did water appear and where did it come from? Accepted Age of the Earth: 4.5 billion years Accretion of materials from formation of the solar system Molten Surface 8000o F Geologic Time Line Precambian 4.5 Bya to 570 Mya (Earth formation, oceans, atmosphere, primitive life, oxygen) Paleozoic 570 Mya to 245 Mya Mesozoic 245 Mya to 65 Mya Cenozoic 65 Mya to present Time Scale 65 mya Cenozoic Era Precambrian Approximately 90% of Earth’s history - 4.5 bya Precambrian – encompasses the time from Earth's formation, approximately 4.5 billion years ago, until the start of the Cambrian period approximately 570 million years ago (mya). Paleozoic Mesozoic 570 mya Human civilization Early Precambrian CO2 (carbon dioxide), NH3 (ammonia), H2O (water vapor) Cooling and condensation of water from the atmosphere Rainfall for millions of years Evidence of Earliest Liquid Water Pillow Lavas 3.35 – 3.5 bya Water and the Tale of the Rocks Basaltic Rocks: 3.9 billion years 3.5 billion years ago Granitic rocks/minerals Minerals indicate Interaction with water Sedimentary rock Earliest Evidence of liquid Water on Earth ~ 4.4 bya (potentially ephemeral) Zircon Crystals Time Line Big Bang: 14 billion years (Hubble Red shift, cosmic radiation) Solar System 4.5 billion years Liquid Water 3.6- 4.4 billion years History of civilization: 8000- 10,000 years Origins of Earth’s Water Sources Asteroids Comets Earth’s Mantle Asteroids 0.1 – 5 % water chondritic meteorites up to 20% water, spherical Could contain more fresh water than earth The largest known asteroid 25 percent of the asteroid belt's total mass Comets Small, but possibly numerous Wrong kind of water? Hydrogen in Water (H2O) Electron (-) Nucleus Proton (+) Neutron Deuterium has a neutron The earth ratio of hydrogen to deuterium is about 4000:1 Comet LINEAR (2000) LINEAR was the first comet with a chemistry that indicated its water had the same ratio of hydrogen to deuterium as the water actually found on Earth. 3.6 million tons (3.3 billion kilograms) of water Volcanic Outgassing Mantle Rocks: 0.1 – 0.5 % water 70% water Origins of Water comet LINEAR Next Lecture: Water and Life