That’s a ripple mark left by water that used to sit on top of this before it was rock. This used to be sand and other sediment - that's why it is called sandstone - which is a type of ...

According to their origin, rocks are divided into three groups, namely, the igneous, metamorphic and sedimentary rocks. Figure 1.1: Approximate mineral compositions of the more common types of igneous ...

Rocks can experience squeezing, stretching, or pushing in different directions in response to stress. This response depends on the type of stress, the rate at which it is applied, the ...