Question

read the passage and answer the following question(s).
dating rock strata
scientists can determine the age of rock layers by measuring radioactive elements within the rock. radioactive elements found in sedimentary rocks decay quickly, so this method can only date sedimentary rocks that are less than 50,000 years old. volcanic rock contains radioactive elements that decay very slowly, so scientists can date volcanic rocks that are much older than 50,000 years.
a team of scientists is investigating a rock formation found in a region. the diagram shows the rock formation that the scientists are investigating.
use the drop - down menus to complete the sentences.
scientists can determine the choose... dates of rock above and below the volcanic layers by using the law of choose... . this law states that younger rock choose... older rock.

Explanation:

The law of superposition is a fundamental principle in geology. It states that in undisturbed sedimentary rock layers, the younger rocks are on top of the older rocks. This is because sedimentary rocks form by the accumulation of sediments over time. Newer sediments are deposited on top of older ones. So, when looking at rock strata (layers), the relative ages can be determined based on their position. If there are volcanic layers, the law of superposition can still be applied to the sedimentary rocks above and below them to figure out the relative ages of those sedimentary layers. Absolute dating (as mentioned in the passage, like measuring radioactive elements in volcanic rocks that decay) gives a numerical age (e.g., 240 million years old, 400 million years old etc. as in the diagram), while the law of superposition gives a relative age (younger or older) relationship between rock layers.

Answer:

Scientists can determine the absolute dates of rock above and below the volcanic layers by using the law of superposition. This law states that younger rock forms on top of older rock.