Download Lecture 1: An Ocean World

Lecture 1: Origin of the Ocean
Terminology
Earth, Theia, Moon, early bombardment, chemical and physical differentiation, inner core, outer core,
mantle, crust, solar wind, magnetosphere, volcanic outgassing, Nuvvuaqittuq Greenstone Belt, light
isotopic carbon, Akilia Island, graphite, diamonds, zircons, lithification, sedimentation, gravel,
conglomerate, pyrite, fool’s gold, pyrite clasts, cement, quartz, calcite, iron oxide, banded iron
formation, hematite, magnetite, red beds, Precambrian, Great Oxygenation Event, eukaryotes, bacteria,
archaeans, thermophile, halophile, acidophile, extremophile, heterotrophic bacteria, cyanobacteria,
protists, green algae, red algae, brown algae, plants, animals, fungi, photosynthesis, stromatolites
Dates:
Age of the Solar System: 4.56 By
Age of the Moon: 4.50 By
Oceans begin to accumulate 4.3 By
Traditional Age for Evidence of Oldest Life 3.83 By
Possible New Age for Evidence of Oldest Life 4.3 By
Time of the Great Oxygenation Event 2.3-2.5 By
Review Questions:
List the five major events/occurrences that took place in early Earth history and explain how these are
relevant to the Earth’s oceans.
How is the source of Earth’s magnetic field different from the remnant magnetic fields of other inner
rocky planets?
How do we know what the likely components of the earliest atmosphere on Earth were?
What form does the likely oldest evidence for the presence of life on Earth take? Explain.
How are pyrite conglomerates and pyrite cement evidence that the early atmosphere was poor in
oxygen?
How are banded iron formations evidence of a) an early ocean rich in dissolved iron, and b) an early
atmosphere and ocean poor in oxygen
How are red beds evidence for the presence of oxygen in the atmosphere?
What are the three domains of life and their members?
How do cyanobacteria build stromatolites?
How might have early life been responsible for changing our reducing atmosphere into an oxidizing one?