How deep can we dig into the Earth? The deepest we can dig into the Earth is around 11.6 kilometers (7 miles) beneath its surface. That’s because the pressure of all that weight above you increases by about 250 pounds per square inch every 10 meters (33 feet) you go deeper. Effectively making it impossible to dig any further.
In addition to that, the heat and pressure at such depths are so intense that no excavation tool can stand up to it for even a few hours. That’s why miners cannot go any further than they already have, despite working on tunnels that are as much as 100 meters (300 feet) below the surface.
We’ve only reached this far because of several technological advances in geotechnics engineering and drilling technologies in recent years.
Anybody who has ever seen an old mining movie knows how difficult digging so deep beneath the ground is. And how many dangers lurk there because of things like gas blasts and cave-ins from unstable rock strata.
What’s Causing All That Pressure?
If you want to understand the pressure, you first have to understand the nature of the mantle, which makes up the Earth’s lower layer. The mantle is made of solid rock, but it’s also really vicious; it acts like a very thick, slow-moving liquid. At the boundary with the Earth’s crust, the mantle is actually under quite a lot of pressure. Because the mantle is under so much pressure, it is squeezed into a layer that is only about 80 kilometers (50 miles) thick. If it weren’t for this pressure, the mantle would spread out from the Earth’s core to its surface, as if it were a viscous liquid.
Why Can’t We Just Go Deeper?
While the mantle is certainly solid rock, it’s not very dense. The pressure of the layers above it compresses it into a liquid. But the rock has a very low melting point, so it never actually turns into a liquid. Instead, the mantle becomes a type of solid called “plastic” rock.
Plastic rock is very rigid, but it can be deformed under pressure. This is why the pressure can’t be overcome: The higher the pressure, the more rock is deformed, making it even harder to break through. It’s like a very dense, solid form of liquid: It is hard to move, and it can deform only slightly.
Is There a Limit to How Deep can We Dig into the Earth?
As we’ve already said, the pressure increases by 250 pounds per square inch every 10 meters. That’s why the deepest we can drill is around 11.6 kilometers beneath the surface. Because the pressure reaches 250,000 pounds per square inch at that depth.
That pressure is about 330 times more than what you feel when you are standing at sea level. It is also roughly equal to the pressure at the bottom of a swimming pool that is about 10 meters deep.
The Dangers of Digging Deeper… and the Biggest Danger of all.
Digging too deep would also change the way the Earth rotates. Imagine that you have a bowl filled with very thick water that is standing on a rotating turntable. The bowl will spin with the turntable. The same is true for the Earth.
The bowl that is the mantle rotates with the Earth, and the spin of both is what makes the planet rotate around its axis every 24 hours. If you could dig 11 kilometers into the mantle, you would reach the solid inner core of the Earth, which is made of iron and nickel.
If you were to dig through the solid inner core, the rotation of the mantle would change. The forces of the rotating iron core on the mantle would tear itself apart.
How Can We Go Deeper If We Don’t Have the Technology Yet?
We don’t have the technology to go deeper than 11 kilometers beneath the surface of the Earth. But we don’t need to go deeper to find the two most valuable minerals in the world: gold and diamonds.
Since these valuable minerals are found in rock that has been formed very slowly and is therefore very rich in minerals, the farther down you go, the greater the chances of finding those gems. You have to give the Earth time, however. It took millions of years for the rock layers to be formed.
And diamonds, for instance, are created under intense pressure and heat. To reach the areas that are rich in minerals and metals, we would have to dig deeper than we have ever done before.
Conclusion
It is interesting to note that diamonds are formed at the Earth’s core. Likewise, gold is formed at the core, too. So, when we dig deeper into the Earth, we are getting closer to the source of these valuable minerals. This is why digging deeper into the Earth is so important.
We must be able to dig deeper to find new minerals, metals, and rare elements that are necessary for modern technologies. Only when we know how deep can we dig into the Earth, we will fully explore and understand the Earth.
