Fountains of the Deep

Could a mineral that has never before been found in a terrestrial rock point to a vast reservoir of water hidden deep within the Earth’s mantle?

A microscopic crystal of a mineral—until now found only in meteorites or synthesized in the lab—may hold clues to the presence of vast quantities of water deep within the Earth’s mantle, according to a recent study.[1]

The ultra-deep diamond found in Juína, Brazil was just five millimeters long, but it contained tiny impurities of ringwoodite—the only known sample of natural terrestrial origin—which may provide evidence of significant amounts of water in the Earth’s mantle.

These minerals have crystalline structures that form only under extreme temperature and pressure deep within the mantle and are difficult to study because they lose their structure if they are brought to the Earth’s surface. But if the minerals become trapped inside diamonds, they stay compressed and intact, as was the case with this particular sample of ringwoodite.

“These high-pressure diamonds give you a window into the deep Earth,” said Graham Pearson, the lead author in the study and a mantle geochemist at the University of Alberta in Edmonton.

Further studies need to be done, but scientists are hopeful the tiny sample could help answer long-standing questions about the origin of our planet’s water.

Water Within the Earth

There are two basic theories as to where the water within the mantle came from. One theory states that ocean water was carried deep underground when sea-floor rocks were subducted by plate tectonics. The other is that the deeper layers of the Earth called the transition zone still contain water that was part of the materials that formed the Earth.

It is interesting that the Book of Genesis indicates:

And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so.

— Genesis 1:6–8

(As an aside, the Hebrew mayim, in the verse above translated “waters,” may not be as specific as we usually assume: over 95% of the matter throughout the universe is plasma, the fourth state of matter, not the liquid of H₂O as we tend to presume.)

What Is Ringwoodite?

The Earth’s upper mantle is made up of minerals called olivines. Ringwoodite is a high-pressure polymorph of olivine that is stable at high temperatures and pressures of the Earth’s mantle between 525 and 660 kilometers deep. Ringwoodite is notable for being able to contain water within its structure, present not as a liquid but as hydroxide ions (oxygen and hydrogen atoms bound together). It was named after the Australian earth scientist Ted Ringwood (1930–1993), who studied polymorphic phase transitions in the common mantle minerals olivine and pyroxene at pressures equivalent to depths as great as about 600 kilometers.

Ringwoodite is thought to be the most abundant mineral phase in the lower part of Earth’s transition zone. The physical and chemical property of this mineral partly determines properties of the mantle at those depths.

If this mineral is indeed proven to be this abundant, it suggests that there could be at least an ocean’s equivalent of water in the mantle transition zone from 410 to 660 kilometer’s deep.[2]

The sample of ringwoodite found in the diamond therefore has the potential to help calculate just how much water the transition zone contains. Using infrared spectroscopy, Pearson’s team found that its tiny fleck of ringwoodite contained about 1% water by weight.

“That may not sound like much,” Pearson says, “but when you realize how much ringwoodite there is, the transition zone could hold as much water as all the Earth’s oceans put together.”

Other scientists point out that the water content of a single crystal does not necessarily represent the water content of the entire zone. Diamonds themselves are produced by an unusual process that is associated with water-rich rock. Pearson agrees. If the transition zone ends up being “spotty” rather than consistently filled with ringwoodite, “Our sample appears to come from one of the wet spots.”

Fountains of the Great Deep

It is interesting that the Bible explains that the Flood of Noah’s time was not just a lot of rain:

In the six hundredth year of Noah’s life, in the second month, the seventeenth day of the month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened.

— Genesis 7:11

The Bible presents a pre-Flood world that had a completely different hydrologic cycle than the current cycle, which involved no rain—or rainbows. Rivers flowed out of the ground to water the land, together with a mist that rose up out of the ground. This subterranean water system was destroyed and replaced with the hydrologic cycle we have today.

The Book of Genesis also indicates that the earth’s atmosphere, hydrosphere, lithosphere, biospheres, orbit, and calendar year were all destroyed or altered by the Flood. The four seasons are an integral part of the hydrologic cycle, which results from the tilt of the Earth’s axis, so it seems it too was altered during the Flood. There are some scientists that suspect the Planet Mars may also have been involved.[3]

More Research Is Necessary

Further studies will be needed to fully qualify these discoveries; however, it is clear that it is premature to jump to simplistic conclusions about the existing structure of the Earth, the Solar System, and certainly the controversies over their origin.

The Book of Genesis

Our Expositional Commentary on the Book of Genesis is one of the most popular (and challenging) of our publications. If you have completed your review of Learn the Bible in 24 Hours, you may find it a refreshing excursion in your journey through the Bible and your joust with the pseudo-science that masquerades as truth in many classrooms. The more one understands the current frontiers of science, the more one is comfortable with the way Genesis reads.

All of our commentaries on DVD and AudioCD are on sale this month.

Coming Soon

The entire field of Biblical Cosmology continues in transition on many fronts: the forthcoming upheavals from the discoveries of “Zero Point Energy” will also be an emerging topic in future articles (and, perhaps, even a Koinonia Institute course) in the coming months.

Watch for them: “Film at Eleven.”