The correct option is 2 and 3 only.
Explanation
The Mid-Atlantic Ridge is a mid-ocean ridge, a divergent tectonic plate boundary located along the floor of the Atlantic Ocean. It is part of the longest mountain range in the world, separating the Eurasian and North American plates in the North Atlantic, and the African and South American plates in the South Atlantic.
Statement-wise Analysis
- Statement 1 is Incorrect. The Mid-Atlantic Ridge is not a deep-sea trench. Deep-sea trenches are typically formed at convergent plate boundaries (subduction zones) where one plate moves under another (e.g., the Mariana Trench). In contrast, the Mid-Atlantic Ridge is a constructive margin formed at a divergent boundary where tectonic plates move apart and new crust is generated by upwelling magma.
- Statement 2 is Correct. Iceland is a prominent part of the Mid-Atlantic Ridge. It represents a unique geological location where the ridge rises above the ocean surface, allowing the divergent boundary between the North American and Eurasian plates to be observed on land.
- Statement 3 is Correct. While most of the Mid-Atlantic Ridge is submerged, portions of it rise above sea level to form volcanic islands. Apart from Iceland, other examples include the Azores, Ascension Island, St. Helena, and Tristan da Cunha.
Key Takeaway
Key Takeaway: The Mid-Atlantic Ridge is a divergent plate boundary and a submarine mountain system, distinct from deep-sea trenches (convergent boundaries). Its highest peaks rise above sea level to form islands such as Iceland and the Azores.