The large cracks in this rock are called expansion cracks. As the overlying rock erodes away, the rock expands, causing the cracks. The cracks are an example of:

1. Erosion

   No. Erosion means that the pieces of rocks are being carried away. The overlying rocks have been eroded, but the cracks are not carrying the pieces to a new location.

2. Weathering

   Yes! As the rocks expand unevenly, tension builds up. When there is enough stress, the rocks break. That breaking of large rocks into smaller pieces is called weathering.

3. Both erosion and weathering

   No. The rocks are being broken (weathering), but the pieces are staying in place, so there is not erosion.

4. Neither erosion nor weathering

   No. The cracks show that the rocks are breaking, which is weathering..

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