Earth’s Continents Formed Due to Intense Asteroid Impacts
Geologists have long debated the origins of the continents, but despite decades of research, their formation mechanisms remain uncertain.
New research suggests that the continents emerged on Earth due to an intense barrage of asteroid impacts that kept the early crust hot and thin, facilitating the formation of buoyant continents.
Challenges in Studying Continental Formation
Studying the formation of continents poses significant challenges as most of the relevant geological evidence has been eroded over time. The oldest known continental rocks date back to around 4.03 billion years ago, while rare basaltic rocks and zircon crystals push the record back to 4.2 and 4.4 billion years, respectively.
Scientists rely on educated guesses and limited data to understand the early Earth’s history.
Competing Theories
Two main theories exist regarding the formation of continents:
- Plate tectonics was already active in the Hadean era, with continental crust forming above subduction zones.
- The early Earth was too hot for rigid plates, and crust formed above mantle plumes rising from deep within the planet.
