Quizlet 10

a supercontinent comprising all the the continental crust of the earth, postulated to have existed 240 million years ago
a universal sea or single ocean that would have surrounded pangaea
Continental Drift
a hypothesis purposed in 1912 by Alfred Wegener that suggested that 240 million years ago all the continents were part of a super-continent called Pangaea and have since drifted to their current locations
Seafloor Spreading
a hypothesis purposed in the 1960's that suggests magma from the earths mantle rises to the surface through rifts or breaks in mid ocean ridges and hardens to form new seafloor. As the seafloor moves in opposite directions, new magma fills in the gap that is created. The new seafloor is eventually destroyed as it descends back into the earth at the ocean trenches
an instrument used to detect small changes in magnetic fields
the study of earths magnetic record using data gathered from iron-bearing minerals in rocks that have recorded the orientation of earths magnetic field at the time of their formation
Mid-Ocean Ridges
Chains of underwater mountains that run throughout the ocean basins of the world. These mountains have rift and crack running down through the middle of them
Ocean Trench
the deepest areas of the oceans where the ocean floor descends back into the internals of the earth
Echo Sounder
a device used to detect the depth of the water by determining how long it takes for a sound impulse to bounce off the bottom and return to the ship. One type of echo sounder is sonar
melted rock within the earth
an iron containing rock that makes up the floor of the worlds oceans. This rock contains the iron bearing minerals that record the history of the earths magnetic field. This rock is covered with sediments.
Marianas Trench
the deepest portion of the worlds ocean located in the western pacific. This is the location where the floor of the pacific ocean descends back into the internals of the earth. the deepest portion of this area is called the challenger deep and plunges to a depth of 7 miles
a genus of extinct land dwelling animals that existed from 251 million to 245.9 years ago. Fossil evidence has been found in south Africa and South America
aquatic relative of reptiles found as fossils from 299 million to 271 million years ago in South Africa and South America
a genus of fossilized woody plants/ferns found as fossils that have been dated to roughly 300 to 200 million years ago
a Triassic land reptile whose fossils have been found in India, Africa, and Antarctica
goves or scratches in the bedrock caused by movement of glacier
a type of rock formed from the burial, compaction, and partial decomposition of swamp plants
Magnetic Reversal
when the earths magnetic field changes polarity between normal and reversed. It is believed to have flutuated about every 300,000 years