The Precambrian Earth to the present 4 5

The Precambrian Earth to the present. 4. 5 Billions years in 2 weeks! Power. Point Notes created by S. Koziol Date : 12/30/2013 Revised : ? /? /? ?

Describe the formations of Describe Earth’s atmosphere and Slides 2 -21 oceans. Identify the origins of oxygen Identify in the atmosphere. Describe the evidence used to Describe Explain the evidence that Explain determine the age of the oxygen existed in the Earth atmosphere during the Understand why scientist Understand Proterozoic. theorize that the early Earth Describe the experimental Describe was hot. evidence of how life Explain the origins of Earth Explain developed on Earth. Crust. Distinguish between Distinguish Describe the formation of the Describe prokaryotes and eukaryotes. Archean and Proterozoic Identify when the first Identify continents. multicellular animals appeared in geological time. Objectives

Earth & our Solar System Most astronomers agree that the solar system, including Earth, formed all at once, and therefore Earth and meteorites should be about the same age.

Earth’s Crust Earth’s earliest crust likely formed as a result of the cooling of the uppermost mantle.

Oldest Mineral The oldest known mineral on Earth is zircon.

Laurentia (North American Craton) Ancient continent that contained core of modernday North America

Precambrian shield Continental core of Archean and Proterozoic rock. aka Canadian shield - The Precambrian shield in N. A.

Craton is an old and stable core of the continental crust - the buried and exposed parts of a continental shield together compose it.

Precambrian shield vs. Canadian shield A Precambrian shield is a continental core of Archean and Proterozoic rock The Canadian Shield is the Precambrian shield of North America.

Orogens are seams where microcontinents were joined together. These seams are belts of deformed rocks that form mountain ranges.

Ozone & O 2 The ozone layer that filters ultraviolet radiation originated from oxygen produced by stromatolites.

Outgassing The process by which volcanoes vent water vapor, carbon dioxide, nitrogen, and other substances is called outgassing.

Photosynthesis Cyanobacteria use the process of photosynthesis to produce energy, and oxygen is given off as a waste product.

Banded iron formation These are deposits consisting of alternating bands of chert and iron oxide.

Red beds Sedimentary rocks younger than 1. 8 billion years that are colored by the iron oxides in them.

Start of life Amino acids have been found in the waters of hydrothermal vents, suggesting that proteins and nucleic acids could have formed there during the Archean.

Miller and Urey demonstrated that the basic building blocks of life were most likely present on Earth during the Archean.

Miller and Urey (continued) Heat, cyanide, and certain clay minerals can cause amino acids to join together in chains.

Prokaryote. An organism composed of a single cell that does not contain a nucleus and is the simplest kind of cell is a prokaryote. Prokaryotes belong to the Kingdom Monera.

Prokaryote vs. Eukaryote A prokaryote is a simple organism composed of a single cell, which does not contain a nucleus. A eukaryote is an organism that is composed of multiple cells, which contain nuclei and are more complex and larger than those of prokaryotes.

Extinctions A major extinction of acritarchs occurred near the end of the Proterozoic, in which widespread glaciations may have played a critical role.

Describe the Describe paleogeography of Laurentia. Discuss the concept of a Discuss passive margin. Describe the Cambrian Describe fauna. Describe the Middle Describe Paleozoic paleogeography. Explain the concept of an Explain active margin and the formation of a clastic wedge. Objectives Slides 23 -38 Describe the Middle Describe Paleozoic fauna. Define the concept of mass Define extinction. Describe the formation of Describe Pangaea. Explain how cyclotherms Explain formed. Identify the importance of Identify amniote eggs. Discuss the causes of the Discuss Late Permian mass extinction.

Paleogeography Ancient geographic setting of an area.

Laurentia During the Cambrian, Laurentia was covered by a sea.

Laurentia - Precambrian On Laurentia, large, sandy beaches formed when sand-sized fragments of quartz were weathered from the rocks of the Precambrian Shield and transported to the shoreline.

Passive Margin When there is no tectonic activity along the edge of a continent, the edge is referred to as a passive margin.

Cambrian explosion During the Cambrian explosion, all but one of the major marine phyla appeared.

Cambrian explosion (continued) The Cambrian explosion was marked by great diversity of life, including the development of animals with skeletons.

Burgess Shale - Contains fossils of soft-bodied Cambrian organisms

Evidence of past lagoons Fragile organisms can live in a lagoon, which is the calm area behind a reef.

Reefs An organic reef is a structure composed of carbonate skeletons made by living organisms, such as coral.

Taconic Orogeny - Mountain-building event named for the mountains of eastern New York State

Clastic Wedge Origins A triangular-shaped deposit composed of sediment eroded from adjacent mountains is called a clastic wedge.

The following provides evidence of the Taconic Orogeny: • angular unconformities • clastic wedges • igneous intrusions

Vascular Plants The ability to transfer water through stems and stalks characterizes vascular plants.

Ancestral Rockies Mountain range in present-day Colorado formed by inland uplift.

Mountain Building The Late Paleozoic was a time of active mountain building.

Cyclothems The series of transgressions and regressions that produce cyclothems were likely produced by glaciations.

Explain the breakup of Explain Pangaea. Distinguish between the Distinguish different characteristics of Mesozoic Orogenies. Describe how paleontologists distinguish among reptile, dinosaur and mammal fossils. Describe the type of tectonism Describe that characterized the Cenozoic orogeny. Objectives Slides 40 -59 Understand the extent of glaciation that occurred in N. A. . Discuss the changes in animals in N. A. during the Cenozoic. Identify the characteristics of primates. Explain what separates hominids from the other hominoids.

200 MYA As North America rifted from Europe and Africa, a continuous rift system called the Mid-Atlantic ridge was formed.

New Oceans As Pangaea split apart, the rifts flooded to form new oceans.

Pangaea break-up Pangaea probably broke apart because it held heat beneath it, which caused the continent to expand then fracture and break apart.

Mesozoic orogenies As a result of the earliest of the Mesozoic orogenies in North America, large bodies of granite called batholiths exist throughout the Cordillera.

Mesozoic orogenies (continued) Orogenic events at the end of the Mesozoic uplifted massive blocks of crust to form the Rocky Mountains.

First Angiosperms - Seed-bearing plants that have flowers Archaefructaceae

Phytoplankton Tiny, ocean-dwelling organisms called phytoplankton made up the base of the food chain during the Mesozoic.

Vertebrates and Invertebrates from among the modern fauna. Invertebrates: crabs, Vertebrates: bony lobsters, shrimps, fishes, sharks, sponges, sea urchins, aquatic reptiles, and modern corals, snails, aquatic mammals and clams.

Mesozoic ammonites Fossils of ammonites are often used as index fossils because these marine animals were widespread and abundant during the Mesozoic.

Early Mammals Early mammals with a single jawbone arose from mammal-like reptiles.

Sauropod The largest land animals that ever lived were the quadrupedal, plant-eating sauropods.

S. W. U. S. tectonism The subduction of the East Pacific Rise coincides with pull-apart tectonism in the southwestern United States.

Pliocene ice age As the Pliocene ice age began, great savannas became arid land many savanna mammals became extinct.

Pliocene ice age (continued) The change of climate caused many of the savanna mammals to become extinct. New animals came to populate the land, including sabre-toothed cats, mammoths, giant vultures, giant ground sloths, and huge wolves.

Pliocene ice age (continued) During the Pliocene, the water of the Arctic Ocean began to freeze to form an arctic ice cap. Glaciers from the arctic advanced and retreated in at least four stages over North America. Glaciers extended as far south as the present-day Ohio and Missouri Rivers.

Pliocene ice age (continued) The southernmost point to which glaciers advanced in North America is marked by the paths of the Ohio River and the Missouri River.