Which term describes the Moon's dark plains that were formed by ancient lava flows?

Which term describes the Moon's dark plains that were formed by ancient lava flows?

• A. Highlands
• B. Rilles
• C. Maria
• D. Craters

Answer: (C)

The Moon’s dark, smooth plains formed by ancient lava flows are called maria. These regions resulted when basaltic lava rose up and flooded large impact basins, then cooled to create flat, dark surfaces that stand out against the brighter, cratered highlands. The name maria comes from the Latin for “seas,” a historical reference to early observers who thought they were seas on the Moon. In contrast, the bright, rugged highlands are heavily cratered, rilles are lava-filled channels, and craters are impact pits. So, maria is the term that describes these lava-flooded plains.

The Moon’s dark, smooth plains formed by ancient lava flows are called maria. These regions resulted when basaltic lava rose up and flooded large impact basins, then cooled to create flat, dark surfaces that stand out against the brighter, cratered highlands. The name maria comes from the Latin for “seas,” a historical reference to early observers who thought they were seas on the Moon. In contrast, the bright, rugged highlands are heavily cratered, rilles are lava-filled channels, and craters are impact pits. So, maria is the term that describes these lava-flooded plains.