Usage patterns
地層が重なるfor strata to be layered/stacked on top of each other
You can clearly see the layers of strata stacked on top of each other in this cliff.
地層を調べるto examine/study a rock stratum
The researchers closely examined the strata in this area.
地層から〈物〉が見つかるfor something (e.g. a fossil) to be found within a stratum
Ancient fossils were found in this stratum.
地層が露出するfor a stratum to be exposed (e.g. on a cliff face)
The strata are exposed due to erosion by the river.
