According to the law of superposition, which layer is oldest? Youngest? In sector 3, stratum D looks like it disappears. Which law makes you expect to find stratum D in sector 3? What could explain the absence of stratum D from sector 3? What law suggests that the rock strata in the graphic did not go through any geologic processes after deposition because the strata are flat?

1. According to the law of superposition, if the terrain was undisturbed, the layer E would be the youngest and the layer A would be the oldest.

2. The law of horizontality states that sediment deposited into water will settle at the bottom in flat, horizontal layers. This would make us expect that we could find layer D in sector 3. To explain the absence, if none of the stratum D species lived there, there would be no stratum D fossils there.

3. The law of faunal and floral succession suggests that the graphic did not go through any geologic processes after deposition.

4. According to the law of cross-cutting relationships, Layer A is the oldest, and Magma F is the youngest.

Oldest layers are at the bottom, youngest on the top