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1) There is a line of seismic activity that runs along nearly the entire stretch of the Americas. It then stretches across the pacific from Alaska to Asia and down the western side almost to Australia, where it cuts back along the Solomon Islands and Fiji. There is a tracing of earthquakes along what appears to be the sea floor through all the oceans. Finally, there is also an extremely strong concentration of seismic activity in the region from Spain through France down to Greece and Turkey.

2) The active volcanoes are located along the western coast from Mexico all the way to Alaska.

They occur together on a very large chain that nearly encloses the Pacific Ocean. They appear separately on the European continent, a portion of the African continent, and in Iceland.

Divergent boundaries occur when plates are moving away from each other. In this situation magma rushes up and forms new crust on the lithosphere. Features that result from this include mid-ocean ridge, volcanic arc, and volcanic island arc.

Oceanic-continental convergent boundaries occur when an oceanic plate and a continental plate move toward each other. They will either collide or undergo subduction when this occurs. Features here include volcanic arcs and mountain chains.

Oceanic-oceanic convergent boundaries occur when two oceanic plates move toward each other. Features here include volcanic arc and volcanic island arc.

Continental-continental convergent boundaries occur when two continental plates move toward each other. Features here include mountain ranges.

The information above can be summarized in the following way:

Divergent Boundary Geographic Feature = mid-oceanic ridges
Oceanic-continental Convergent Boundary:
Geographic Feature 1 = volcanic island
Geographic Feature 2 = mountain chain
Oceanic-oceanic Convergent Boundary
Geographic Feature 1= volcanic island arc
Geographic Feature 2 = ocean trench
Continental-continental Convergent Boundary Geographic Feature = mountain range

3) The oldest rocks in the ocean basin will be located where there is the least amount of volcanic activity. To me this appears to be in the Arctic and Antarctic regions. The youngest rocks in the ocean basin will be located where there is the most amount of volcanic activity, which appears to be along the border of the Pacific Ocean.

The highest place on Earth is Mt Everest. This is located at the conversion of the Indo-Australian plate and the Eurasian plate. The lowest place on Earth is the Mariana Trench. This is due to the interaction of the Mariana and Pacific plates.

There are no truly significant geographic features at transform boundaries because the only change is the relative position. There is no collisional upheaval or tearing apart of the crust in these areas.

The mid-ocean ridge runs into continental crust in the area of northern Mexico and the southern United States.


4) Active volcanism and the youngest rocks would be expected on the island of Hawaii.

The oldest rocks are on Kauai, which is the furthest northwest.

Loihi lies to the south and east of the big island of Hawaii. It rises ten thousand feet from the ocean floor and is only three thousand feet from the surface.

5) Hawaii modern 0 km
Maui 0.8 M years 125 km
Oahu 3.7 M years 400 km
Kauai 5.1 M years 600 km
Midway 27.7 M years 2500 km

6) A) 2500km / 27.7 M years = 90.25 km per million years

B) 0.00009025 km per year

C) 9.025 cm per year

D) 9.025 cm per year

7) The Pacific Plate was moving north when the Emperor Chain was forming.

The linear direction of the island chain changes by about 60 degrees to the southeast.

This suggests that the plate motion over time changed abruptly from traveling north to traveling about 30 degrees north of west.