Question

mud was deposited at the bottom of a lake. over time, the lake dried up, and the area became a sandy desert.
thousands of years later, the environment became wet again. a new lake formed, and mud was deposited on top of the older sediment.
which rock sequence is more likely to form from the sediment layers described above?
chart 1: younger (top) to older (bottom) layers: sandstone, shale, sandstone
chart 2: younger (top) to older (bottom) layers: shale, sandstone, shale

Explanation:

Step1: Identify sediment types

Lake mud → shale; desert sand → sandstone.

Step2: Order layers by age

Oldest: first lake mud (shale) → desert sand (sandstone) → youngest: new lake mud (shale).

Step3: Match to rock sequence

Sequence: oldest shale → sandstone → youngest shale.

Answer:

The Lower Graph (with layers: younger shale, sandstone, older shale)