Explain how scientists use geologic time to determine the age of landforms.

Following are the techniques or methods or approaches we can say that were used by the scientists to determine the geologic age:

1. Relative age dating

2. Absolute age dating.

3. Radiation measurement.

4. Stratigraphic superposition.

5. The fossil record.

The scientists used the method of relative dating to divide Earth's past in different chunks of time when alike organisms were on Earth. After that, to discover the actual number of years ago that events occurred, the scientists used the method of absolute dating.

Geologic time uses the layers of rock to describe the relationships of events and their sequence in chronological order over the history of Earth. The layering is a result of the buildup of tiny bits of rock, sediment, or lava cooling at the surface over many years. Think of it like a stack of pancakes—the bottom layer is the one that was placed first and therefore is the oldest. The sediments that create the layers of Earth are stacked one on top of the other.