Final answer:
Scientists have gathered evidence of volcanic activity on Venus that suggests it has radically changed the planet's surface. Venus lacks water or ice, and with low surface wind speeds, there is little to no erosion, meaning geological features are well-preserved.
Step-by-step explanation:
Volcanic activity on Venus is evidenced by fresh-looking impact craters, low erosion rates, and lava plains, suggesting resurfacing between 300 and 600 million years ago. Young volcanic mountains and igneous rock samples also support widespread volcanism. Unlike Earth, Venus does not have plate tectonics but displays 'blob tectonics' from interior heat transportation.
The surface of Venus, as seen through radar mapping, is mostly composed of lowland lava plains resembling Earth's landscapes, if not for the processes of erosion and sediment deposition.
Clear evidence comes from the large impact craters that appear fresh, indicating a low rate of erosion. The surface has been freshly resurfaced by volcanic activity, with estimates suggesting a planet-wide volcanic event occurred between 300 and 600 million years ago. This history of volcanic activity is also supported by the fact that Venus' landforms, like younger volcanic mountains, are linked to hot spots that transport heat from the planet's interior to the surface through mantle convection.
The Venera landers have also provided direct evidence of igneous rocks, primarily basalts, confirming volcanic activities. In addition, the terrain has flat, layered lava flows, further supporting the presence of volcanism. With most of the planet's surface not older than 500 million years, Venus showcases features such as coronae and pancake volcanoes, indicative of 'blob tectonics' caused by the upwelling of hot material from the interior.