E., The sediment is thin near the ridges, and thickens as you go away from the ridges, because the rocks near the ridges are young and have had little time to accumulate sediment, whereas rocks farther away are older and have had longer to accumulate sediment.Sea floor is made at the spreading ridges, and moves away on both sides. Sediment piles up over time, and while there are variations in sedimentation rate, the huge difference in age of the sea-floor rocks (140 million years near the edges of some ocean basins, to essentially zero at the ridges) is the main controlling factor on sediment thickness. Fish actually poop wherever they travel, and tend to go all over the oceans., Points Earned:, 1/1Your Response:, E 8., When discussing earthquakes that happen in the upper part of the Earth’s crust, geologists believe that most are caused by elastic rebound. This means:, A., Rocks on opposite sides of a break, or fault, move in opposite directions, get stuck against each other for a 9., On the Richter scale of earthquake intensity:, A., The ground is shaken 6 times more by a magnitude-6 quake than by a magnitude-1 quake.
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