Scientists want to plumb the Earth for one of its last secrets. An international group of researchers led by Japan’s Agency for Marine-Earth Science and Technology say they plan to be the first to successfully drill into the mantle, that is, the region sandwiched between the planet’s outer crust and its inner core. Although the mantel makes up about 80 percent of the Earth’s mass, much of it remains a geological enigma. “We don’t know the exact [composition] of the mantle yet,” researcher Natsue Abe told CNN.
To access the mantel, JAMSTEC will deploy the Chikyu, one of its biggest and most sophisticated drilling vessels, to penetrate 2.5 miles of ocean, then another 3.7 miles of sea floor (a.k.a the crust). The Japanese government is backing the expedition in the hopes that the data gleaned will help scientists better predict earthquakes.
“In Japan we have some volcanoes, earthquakes and such kind of natural hazards,” Abe said. “People [want to create] some monitoring or analysis equipment but we don’t know … what kind of factor to use. So we need to know the natural system more clearly or precisely … we have to observe the Earth more precisely.”
All three drilling sites currently under consideration are located in the Pacific Ocean. The first is off Hawaii, the second off Costa Rica, and the third is off Mexico. “We already drilled and have taken some samples from the ocean floor but [only] from the top,” Abe said. “[We want] to dig from the ocean floor to the deep pristine mantle.”