Article by Patrick Kiger.
…An international team of scientists who call themselves the 2012 MoHole To the Mantle project [are] counting upon international support for a $1 billion effort in which a Japanese deep-sea drilling vessel, the Chikyu, would burrow into the bottom of the Pacific Ocean to dig deeper than anyone has ever gone before. The plan is to go right through the Earth's crust, the rocky top layer of the planet, which is 18 to 37 miles (30 to 60 kilometers) thick on land, but as little as 3 miles (5-kilometers) thick at its thinnest spots on the ocean floor [source: Osman]. If the Chikyu's drill rig breaks through a transitional boundary called the Moho, it would reach the Earth's mantle, the mysterious 1,740-mile (2,900-kilometer) thick layer between the crust and the planet's hot, molten core [sources: USGS, ScienceDaily].
Image credit: Surachit