Explain how the texture of a rock surface (whether it is smooth or rough) affects how fast it physically weathers by water.(4 points)
1) Surface area: The texture of a rock surface affects the amount of surface area available for water to interact with. A rough surface will have more uneven and exposed spaces compared to a smooth surface. This increased surface area allows water to penetrate deeper into the rock, increasing the rate of physical weathering.
2) Water retention: A rough surface tends to have more crevices and micro-cracks, which can trap water. As water gets trapped in these irregularities, it can freeze and expand during cold weather. This freeze-thaw cycle exerts pressure on the rock, causing it to physically break down more quickly compared to a smooth surface.
3) Abrasion: Rough surfaces can also intensify the abrasive action of water. As water flows over a rough surface, it carries sediments and particles that can act as natural sandpaper, rubbing against the rock and wearing it away. This constant abrasion speeds up the physical weathering process.
4) Chemical interactions: A rough surface may provide more opportunities for chemical reactions between water and the minerals present in the rock. Water can dissolve certain minerals in rocks, causing them to weaken and break apart. With increased contact between water and the rock surface, the chances of chemical weathering occurring are higher, further accelerating physical weathering.