Translation

複数の層 / 地層群 / 階層

Meaning

Strata means layers or levels within a larger structure, especially rock, society, or data. It is plural: the strata are visible. The singular form is stratum.

Examples

• 崖にはいくつもの地層がはっきり見えました。
  Several strata were clearly visible in the cliff.
• 調査は複数の社会階層を比較しました。
  The survey compared several social strata.