One of the best-known examples of a hotspot track is the Emperor Seamount-Hawaiian Ridge.
![yellow stone flood basalts yellow stone flood basalts](http://yellowstonehazardmap.weebly.com/uploads/1/3/1/9/13198347/7258503_orig.jpg)
Dating rock samples from those volcanoes also revealed that they were arranged in chronologic order, getting progressively younger in one direction along the paths. As geologists began collecting more and better seafloor data in the 1950s and 1960s, they noticed strings of volcanoes lined up along straight paths. Hotspots were first recognized after plate tectonic theory revolutionized geology. While most volcanic activity occurs near the boundaries of tectonic plates, hotspot volcanoes are unique because they can develop in the interiors of plates far from their boundaries. Evidence for these past eruptions has been documented by careful mapping of geologic units, as well as chemical analyses and dating of volcanic deposits.
Yellow stone flood basalts series#
As the North American tectonic plate moved southwest through time over the mostly stationary plume, a series of eruptions occurred, forming a hotspot "track." The result is a chain of ancient volcanic fields that started over 16 million years ago near the Idaho/Nevada/Oregon border and that gets progressively younger across southwestern Idaho and the eastern Snake River Plain.Īt least seven volcanic fields have been identified: McDermitt (which began 16.5 million years ago), Owyhee-Humboldt (15 million years ago), Bruneau-Jarbidge (12 million years ago), Twin Falls (10.5 million years ago), Picabo (10 million years ago), Heise (6.5 million years ago), and Yellowstone (2 million years ago). Volcanic hotspots are fed by plumes of hot material rising from deep in the Earth, which can result in the formation of magma closer to the surface and that might eventually erupt. After the formation of O‘ahu, the volcanoes can be categorized as belonging to either the "Loa" (black triangles) or "Kea" (white triangles) trends, based on their location and the composition of their rocks.
![yellow stone flood basalts yellow stone flood basalts](https://cdn.images.express.co.uk/img/dynamic/151/750x445/1293459.jpg)
The inset shows the volcanoes in the main Hawaiian Islands. Map showing the submarine shape of the Hawaiian hotspot track, which extends from the Hawaiian Islands, through a prominent bend in the middle of the Pacific Ocean, to Alaska's Aleutian Islands.