My next series of posts about the Geology of the National Parks Through Pictures is for a set a parks we hit up while visiting the Big Island of Hawaii at the end of March in 2018. We were able to visit all four parks across the big island. Many of them are going to have similar geological features, since they are all located on the same volcanic island, so we will start with the big one.
You can find more Geology of the National Parks Through Pictures as well as my Geological State Symbols Across America series at my website Dinojim.com.
|Graphic depiction of the Hawaiian hotspot. Image courtesy of Clark Science.
The source of the magma for a hotspot is an area known as a mantle plume. This spot is essentially "fixed" within the Earth and doesn't move while the plates on the Earth's surface are all moving around on top of it. As the plate moves, the Pacific Plate in this instance, over the hotspot, volcanoes pop up out of the sea floor. As the plate continues to move on, the old volcanoes are pulled away from the hotspot source and die off, while new volcanoes are created. The hotspot is currently located beneath the Big Island and actually a bit to the southeast of the Big Island, where is a new island is currently being formed called Lō'ihi. Lō'ihi has the potential to become a new island or could possibly fuse with the Big Island. On the Big Island there are actually five subaerial volcanoes, of which three are considered active (last erupted in the last 10,000 years), Kilauea, Mauna Loa, and Hualalai. Within Hawai'i Volcanoes National Park, we are only looking at Kilauea.