The correct answer is - The Principle of Superposition.
The Principle of Superposition suggests that the newest rocks are on the top while the oldest rocks on the bottom of the layers, or with other words, the new rocks are always deposited on top of the older layers, thus making a horizontal type of layers in proper order from the oldest to the youngest layers as we go from the bottom to the top. By this principle, it comes as the lava flows or the deposited sediments are covering the layers that are already in place and are naturally ordering themselves by age.
The superposition principle is the geological principle that affirms the existence of soil sedimentation, or over time. This sedimentation allows the deposition of strata in chronological order on top of layers of soil or rocks, creating more layers. As this process is chronological, it is possible to notice that the deeper layers are older layers in relation to the newer layers, which were deposited more recently.
Because the velocity of sediment settling (deposition) is positively related to grain size for waterborne sediments, fluvial deposits are more likely than glacial deposits to be well sorted.
World War I and II. These wars caused lots of economic growth and development because there was a pressure to create better inventions. Having better technology could mean the win or lose of a war. :D
