Hannah is comparing a rock from a riverbed and a rock from deep underground. One is very smooth, and the other has very rough edges. Explain why each rock was probably found in that location.
What has happened continuously to the rock in the riverbed? What has happened to the rock from deep underground?
Think about what the river would do to the rock. Scroll down to continue.
Erosion. If the rock was eroded, it would be smooth. In the cave, erosion can't occur. So it would be a rough rock. I hope that helps you.
To understand why each rock was likely found in its respective location, we need to consider the geological processes that affect rocks in riverbeds and deep underground.
The smooth rock from the riverbed:
1. Rivers continuously transport loose sediments like rocks, pebbles, and sand downstream. As these sediments move along the riverbed, they are subjected to the erosive force of water.
2. The constant rubbing and tumbling of the sediments against each other, as well as against the riverbed, gradually wear down sharp edges and rough surfaces, resulting in smoother rocks over time.
3. Therefore, the smooth rock was most likely found in the riverbed because it endured the abrasive action of moving water for an extended period, resulting in the erosion of its rough edges and the creation of a significantly smoother surface.
The rock with rough edges from deep underground:
1. Rocks found deep underground are often subjected to different geological processes compared to those on the Earth's surface.
2. In deeper parts of the Earth's crust, rocks experience intense pressure and temperature conditions that contribute to their formation and alteration. These processes, known as metamorphism, can lead to the creation or transformation of minerals within the rocks.
3. Metamorphism can result in the formation of minerals with distinct crystal structures that often exhibit rough or jagged edges when exposed on the surface.
4. If the rock with rough edges was excavated from deep underground, it likely underwent metamorphic processes that caused the formation of minerals contributing to the jagged edges we observe.
By considering the geological processes associated with riverbeds and deep underground environments, we can explain why the rock from the riverbed is smooth due to water erosion, while the rock from deep underground has rough edges as a result of metamorphic processes.