Erosion in Spire CoveThomas PaleenAward: Top 100
School: minnetonka high school The islands in this photo, taken in Spire Cove, Alaska, were formed by erosion over thousands of years, by waves constantly battering them. These islands, once part of the mainland, have been shaped by the sea into the islands they are now. Sediment in the water grates against the soft shale rocks that these islands are made of, and causes friction, which causes the soft rocks to crumble, shaping the islands over time. The islands crumble because the friction force overpowers the stones ability to hold together, causing them to crack under the stress and eventually break off. These islands are smaller on top because there are more hard rocks near the bottom of these islands, and more soft rocks on top that crumble easily. The softness of the sedimentary rocks is the reason that they were formed into these islands, and they might not be here if they were made of a different hardness of rock. The water will continue to erode these islands, until eventually they collapse, and the sea will consume them. 
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