Scientists using an ocean drilling vessel JOIDES Resolution have dug the deepest hole ever in rock from Earth’s mantle – penetrating 4,160 feet (1,268 meters) below the Atlantic seabed – and obtained a large sample of our planet’s most voluminous layer.
This cylindrical core sample is providing insight into the composition of the upper part of the mantle and the chemical processes that occur when this rock interacts with seawater over a range of temperatures.
Mantle rocks generally are inaccessible except where they are exposed at locations of seafloor. One such place is the Atlantis Massif, an underwater mountain where mantle rock is exposed on the seafloor.
Atlantis Massif is located in the middle of the Atlantic just west of the vast mid-Atlantic Ridge that forms the boundary between the North American plate and the Eurasian and African plates.
Using equipment aboard the vessel, the researchers drilled into mantle rock about 2,800 feet (850 meters) beneath the ocean surface.
The core sample they recovered comprises more than 70% of the rock – 2,907 feet (886 meters) in length – from the hole they drilled.
About mantle
The mantle is the mostly solid bulk of Earth’s interior.
The mantle lies between Earth’s dense, superheated core and its thin outer layer, the crust.
The mantle is about 2,900 kilometers (1,802 miles) thick, and makes up a whopping 84 percent of Earth’s total volume. It is a layer of silicate rock.
