Boring Through The Crust Of The Earth
By James Donahue
We noticed a report not long ago that a scientific team comprising The Integrated
Ocean Drilling Program recently drilled a hole successfully through the outer crust of the Earth and reached the “Mojo.”
Mojo is a nickname for the Mohorovicic discontinuity, or a division between the
crust and the hot mantle.
The hole, drilled on the floor of the Atlantic Ocean where the crust is believed
to be thinner, involved drilling for 4,644 feet, something short of 5,280 feet or a mile.
Having once worked among the oil well drilling rigs in my younger years, I wondered
why a mile-deep hole in the ground was considered such an important milestone. Some of the rigs I worked around went at least
2000 feet down within weeks and we didn’t think much of it.
One Alaskan drill site, believed to be among the deepest in the world, went to
20,203 feet. Some of the copper mines in the Upper Peninsula of Michigan are known to have been dug my miners to depths of
over a mile.
It is said the gold mines in South Africa go so deep in the earth that miners
work in extreme heat because they are close if not inside the mantle. That means they could be miles down.
The deepest research borehole known was drilled in Russia. A massive rig drilled
to over 12 kilometers, or an estimated 7.4 miles into the Continental Crust. It was reported that the drilling crew found
fractures, fissures and water-bearing zones there where they were not expected.
So with all of this digging and drilling that has been going on for decades, what
is the significance of the Moho Project? The National Science Foundation claims it is the third deepest hole ever made in
the floor of the sea and that rocks brought back to the surface are giving new information about the composition of the Earth.
Geologist Barbara John said in a story for Live Science that further drilling
is expected, following a complete analysis of the material removed from the drilling to date.
“Our major result is that we’ve recovered the lower crust for the
first time and have confirmed that the Earth’s crust at this locality is more complicated than we thought.”
Once the drill gets into the mantle, the geologists will know it because the material
brought up will have different texture and chemistry.
The project is expected to continue for 10 years at a cost of $1.5 billion. And
that begs the question . . . is the information they glean from the work going to be worth the price?
Apparently scientists from around the world think so because the drillship, JOIDES
Resolution, is at it again this year. The vessel is on a two-month voyage with 29 scientists from seven participating nations.
To date, the team reports making six deep drills and extracting core material from the bed of the Pacific Ocean that is proving
invaluable in establishing a record of the Earth’s climate history.
What they are discovering is that the planet has had a history of warming and
freezing and there were times in the past when alligators lived as far north as the Arctic, palm trees existed in the Rocky
Mountains, and greenhouse gas concentrations have been much higher than they are today.
We might sound somewhat cynical when we suggest that such deep water drilling
might not be necessary to make such discoveries. But then, we are not geologists so what do we know?
Looking at it logically we think that proofs might be easier to find than this
team is willing to admit. This planet has had so many natural upheavals from exploding volcanoes and large objects colliding
from space that studying the composition of the underside of our planet should not be that difficult, or complicated.
The natural movement of the planet’s plates are forcing the constant upheaval
of land mass which exposes material from deep in the Earth.
There is a large hole in the earth at Vredefort, South Africa, where a giant meteorite
or asteroid slammed into the Earth over 2000 million years ago, blasting a hole 25 kilometers deep and causing the crust of
the Earth to blow outward, bringing the deep crustal rocks right to the surface.
We might suggest that the scientists use some of this cash to buy plane fares
to South Africa to either visit the site at Vredefort, or else go down with the diamond miners to examine first-hand what
the planet looks like a mile or two below the surface.