Mauna Loa, the biggest volcano on Earth — and one of the most active — covers half the Island of Hawaii. Just 35 miles to the northeast, Mauna Kea, known to native Hawaiians as Mauna a Wakea, rises nearly 14,000 feet above sea level. To them it represents a spiritual connection between our planet and the heavens above.

These volcanoes, which have beguiled millions of tourists visiting the Hawaiian islands, have also plagued scientists with a long-running mystery: If they are so close together, how did they develop in two parallel tracks along the Hawaiian-Emperor chain formed over the same hot spot in the Pacific Ocean — and why are their chemical compositions so different?

“We knew this was related to something much deeper, but we couldn’t see what,” said Tim Jones, an earth science Ph.D. student at Australian National University and the lead author of a paper published in Nature on Wednesday that may hold the answer.

Mr. Jones and his colleagues developed a model that simulates what’s happening in our planet’s mantle, beneath the crust that we live on, offering a window to the center of the Earth — or close to it. Their study may one day allow a reconstruction of the history of the movement of Earth’s plates — and the processes linked to these movements over billions of years, like mass extinction events, diamond and oil deposits, and changes in climate.