How Weathering of Rock Occurred Deep Beneath the Ground

Water is one of the greatest destructive agents causing the weathering of the rock, even deep beneath the ground. 
Water flows from high ground to low ground, which is generally the mean sea level on Earth, due to gravity. In doing so, they will find the shortest path and permeates through any weak spot to reach the destination. Therefore it travels not only on the surface, it also penetrates through the ground and rock. This water often carries impurities and chemical solutions which form evidence of the water path through the rock. 
This Sandstone rock sample shows distinct mark cutting through the bedding and is found at 12m below ground level, 3m into the mainly Sandstone bedrock.