Rivers carved deep valleys, known as gulches, radiating from the central peaks out to the sea. The Birth of the Hawaiian Chain Oahu is part of a chain of islands that owes its existence to a geological phenomenon known as a hotspot.
Age Sequence of the Hawaiian Islands: Understanding Oahu's Geological Timeline
Stage One: The Shield Volcano Phase Long before the recognizable outline of Oahu existed, the island was a massive, broad-shield volcano rising from the ocean floor. These flows traveled great distances, layering upon each other to build a colossal structure that likely rose thousands of meters above the surrounding seafloor.
This stage, similar to the current formation of the Big Island, involved relatively gentle eruptions that spread vast amounts of fluid basalt lava. A second major volcano, the Ko'olau volcano, began to form.
Age Sequence of the Hawaiian Islands: Understanding Oahu's Geological Timeline
This created a large basin. Unlike tectonic plate boundaries, a hotspot is a fixed plume of intense heat rising from deep within the Earth's mantle.
More About How was oahu formed
Looking at How was oahu formed from another angle can help expand the discussion and give readers a second clear paragraph under the same section.
More perspective on How was oahu formed can make the topic easier to follow by connecting earlier points with a few simple takeaways.
