Does the Earth’s Mantle Preserve Evidence of Its Origin?

Why Such Bold Claims?

According to one of the study’s co-researchers Richard Carlson, director of the Department of Terrestrial Magnetism at the Carnegie Institution for Science in Washington, DC, “The fact that these materials have survived through 4.5 billion years of dynamic earth activity tells us something about the nature and limits of motion in earth’s interior, the source of flood [volcanic] basalt events and eventually about the processes that formed the earth.”3

The evolutionary story about the earth’s origin and formation says the earth formed between 4.5 billion and 4.6 billion years ago, taking shape as matter surrounding the young sun began to clump together. The heat of this matter coming together apparently made the developing orb melt, and so the earth soon separated into two main layers—a metallic iron core on the inside, and a silicate-rich rocky mantle on the outside.

For years, evolutionary scientists had thought that the early mantle rock had been destroyed as it subsequently melted and then mixed into other and newer rocks to form the earth’s crust, its outer “skin.” But now, new chemical analyses appear to show that some of the early mantle rock may have survived until today in rock formations called flood basalts, which were produced by enormous eruptions of huge quantities of lavas.

These lavas are supposedly only 60 million to 120 million years old (based on radioisotope dating of them), but some of the material within them is now claimed by these researchers to contain pieces of the early mantle.

In their investigations, the research team analyzed different isotopes found within these ancient lava flows.4 In particular, they were looking for the isotopes of tungsten (abbreviated with the symbol W), a metallic element that’s commonly used in the filaments of incandescent light bulbs.

According to the researchers, tungsten has especially useful isotopes. When an isotope of the element hafnium (hafnium-182 or ¹⁸²Hf) undergoes radioactive decay (that is, its nucleus is unstable and so ejects an unwanted particle plus gives off radiation), it creates tungsten-182 ¹⁸²W). According to Carlson, hafnium-182 (¹⁸²Hf) went extinct (decayed completely away) within less than 50 million years after the formation of the solar system, supposedly about 4.567 billion years ago.

Apparently, at today’s rates of radioactive decay it takes about 8.9 million years for half a given quantity of ¹⁸²Hf to decay into ¹⁸²W (that is, the decay half-life of ¹⁸²Hf is 8.9 million years). So Carlson says this makes ¹⁸²W a good measure of extremely old rocks. Its parent ¹⁸²Hf was supposedly only around when the earth formed and then went extinct, and evidently there is no other source of ¹⁸²W. So according to this scenario, to find ¹⁸²W in rocks today means that ¹⁸²W comes from the ¹⁸²Hf atoms present in the earliest history of the earth, even if the ¹⁸²W atoms it produced were subsequently recycled through earth’s rocks since their formation back at the beginning.

Most earth rocks have compositions with a similar mix of tungsten (W) isotopes.

Most earth rocks have compositions with a similar mix of tungsten (W) isotopes.5 That means the ratio of ¹⁸²W compared to ¹⁸⁴W appears to be always about the same. However, some supposedly ancient rocks radioactively dated at 2.8, 3.8, and 3.96 billion years old contain elevated amounts of ¹⁸²W compared to ¹⁸⁴W. This has been attributed to the supposed addition of extra ¹⁸²W atoms to these rocks when they formed.6 Those extra ¹⁸²W atoms were once resident in the earth’s mantle, supposedly left over from the decay of ¹⁸²Hf during the earth’s earliest history. Then the melting of mantle rocks produced magmas (molten rocks) that were squeezed up into and onto the earth’s continental crust to build the terrains where these ancient rocks containing the extra ¹⁸²W are now found.

Since these discoveries of this extra ¹⁸²W in these ancient continental rocks, the search has been on to find more places where the rocks store similar supposed geochemical traces of the earth’s earliest mantle rocks. After much research, this team of eight Canadian and US scientists found basalt on Baffin Island from a 60-million-year-old volcanic eruption and basalt on the Ontong Java Plateau (just north of the Solomon Islands) from an approximately 120-million-year-old volcanic eruption, both of which had slightly more ¹⁸²W than younger volcanic rocks.

The researchers were able to measure these small differences in ¹⁸²W thanks to recent significant improvements made to mass spectrometers. These analytical tools are able to measure the mass of individual atoms of an element, and thus distinguish between the different isotopes in an element. As already indicated, each isotope has a different number of neutrons in the nuclei of its atoms, so the atoms of each isotope have a unique mass that the mass spectrometer can detect. However, it should be noted that mass spectrometers only provide analytical measurements of isotopes relative to other isotopes. Thus in this instance, the research team measured ¹⁸²W/¹⁸⁴W ratios, that is, the quantity of ¹⁸²W atoms per the number of ¹⁸⁴W atoms in their basalt samples.

“We have only had the ability to do this for about a decade,” says Carlson. “And in that decade, we are getting a much clearer picture of the events that occurred over the first tens to hundreds of millions of years of Earth history.”7 Of course, that claim is based on assumptions (or beliefs) about the past and a model (or faith position) of how the solar system and the earth in it apparently formed.

What Was Really Found?

So what really is the significance of what was found? The basalt lavas of Baffin Island and the Ontong Java Plateau contain elevated and distinctive ¹⁸²W/¹⁸⁴W ratios which suggest that the mantle source areas of these basalts had originally contained more ¹⁸²W atoms than other areas within the earth’s mantle.

That different areas within the earth’s mantle contain different isotopic compositions is not a new discovery. It has been known for decades, ever since geologists have been able to measure the isotopic ratios of atoms presumed to be derived by radioactive decay in rocks sourced from the mantle.8 Several well-known and well-documented examples illustrate this.

Recently erupted basalt lavas have been found to yield excessively old radioisotope dates. Basalt lavas erupted in 1800–1801 at Hualalai, Hawaii, yielded potassium-argon (K-Ar) “ages” of up to 22.8 million years.9 And basalt lavas, which erupted so recently in the Western Grand Canyon area that they spilled over into the canyon and temporarily blocked the Colorado River, yield a rubidium-strontium (Rb-Sr) isochron “age” of 1,143 million years, almost identical to the Rb-Sr isochron “age” of 1,111 million years for basalt lavas found buried deep in the Eastern Grand Canyon between Precambrian (pre-Flood) sedimentary rock layers.10 Finally, the recently-erupted basalt lavas on the many islands which dot the earth’s oceans have all been found to yield lead-lead (Pb-Pb) isochron “ages” of between 1,000 and 1,500 million years,11 which became known as the “lead paradox.”

None of the “ages” are the true ages of these rocks.

None of the “ages” are the true ages of these rocks. These basalts were all sourced from different areas in the earth’s mantle. This is evident, because basalt has a distinctive composition (both its mineral content and bulk chemical composition), which is very different from the composition of the earth’s continental crust (the rocks which make up the continents). Tracing the conduits through which the basalt lavas have been erupted tracks their sources down into the mantle, where the rocks there had melted. So if different basalt lavas have such different isotopic compositions (which yield such erroneously old apparent “ages”), then these inherited “ages” must obviously represent the isotopic compositions of the mantle areas from which the lavas were sourced (rather than their true ages). This realization forced geologists to conclude that the earth’s mantle consists of various domains with different isotopic compositions.12 And subsequent research studies have only confirmed this.

So when this research team found these basalt lavas with elevated and distinctive ¹⁸²W/¹⁸⁴W ratios, they immediately concluded these basalts had been sourced from unique areas within the mantle. And because of their belief as to how the earth formed, they reasoned that these source areas within the mantle must be remnants of domains in the earth’s mantle that have survived since the earth formed over 4.5 billion years ago, when ¹⁸²Hf atoms had been in those domains.

Mantle Domains and Flood Basalts

What then was their explanation as to how these distinctive mantle domains formed with elevated ¹⁸²W/¹⁸⁴W ratios? They suppose as matter from the solar nebula condensed to form the earth over 4.5 billion years ago, the heavier metals (principally iron and nickel) separated to form the core, leaving the lighter silicate minerals to form the surrounding mantle.13 Since W is a metal with particular properties, it was partitioned into the core; but the Hf concentrated in the mantle. In time the ¹⁸²Hf in the mantle decayed to ¹⁸²W, the mantle’s ¹⁸²W/¹⁸⁴W ratio got higher. Then a large body with a very much higher ¹⁸²W/¹⁸⁴W ratio crashed into the earth, smashing its way deep into the earth’s mantle. That body’s core was thus incorporated into the earth’s core, and its mantle into the earth’s mantle. However, since that impacting body had a very much higher ¹⁸²W/¹⁸⁴W ratio, where its mantle material ended up residing within the earth’s mantle resulted in a domain with a much higher ¹⁸²W/¹⁸⁴W ratio than surrounding mantle areas.

The earth’s mantle then continued to develop. However, they say there were many smaller bodies which subsequently crashed into the earth, contributing further material. That material had lower ¹⁸²W/¹⁸⁴W ratios, so when it mixed into the upper parts of the earth’s mantle, it thereby diluted their ¹⁸²W/¹⁸⁴W ratios. The net result, they believe, were domains at the base of the earth’s mantle, just above the mantle-core boundary, that had much higher ¹⁸²W/¹⁸⁴W ratios than the rest of the mantle.

Now fast forward more than 4 billion years. As a result of the heat still coming out of the earth’s core to warm the base of the mantle, melting had occurred within the rocky mantle. Melted rock is less dense than the surrounding mantle, so it rises and pushes aside the mantle above it, which causes stirring of the mantle, a process called convection. Such rising plumes of hot rock produced, and were the driving force of, plate tectonics. Where the hot rock broke through to the earth’s crust, the earth’s crust was fractured, and the fragments (plates) were pushed aside as the hot rock erupted as lavas. The hot mantle plume below the erupting lavas also spread sideways underneath the crust, thus pushing with it the crustal plates either side of the rift zone where the hot rock had erupted.

Thus, 120 and 60 million years ago, voluminous melting of the domains at the base of the mantle with high ¹⁸²W/¹⁸⁴W ratios caused huge plumes of melted mantle rock to rise, the first to the region near the Solomon Islands in the western Pacific Ocean basin, and the second to the Baffin Island area in the North Atlantic Ocean basin. Where these hot mantle plumes broke through, they erupted prodigiously humungous volumes of basalt lavas, on a scale many orders of magnitude greater than anything we see happening today. Hence these basalt lavas are called flood basalts, because the erupting lavas flooded those areas and left behind huge piles of basalts in those two places. The Ontong Java Plateau near the Solomon Islands is the largest accumulation of erupted basalts known on the earth. And these Baffin Island and Ontong Java Plateau flood basalts have now been found to contain high ¹⁸²W/¹⁸⁴W ratios that are claimed to have been sourced from mantle domains, which survived from the earth’s earliest history.

Understanding This Discovery Within the Biblical Framework of Earth History

God the Creator’s eyewitness testimony in Genesis 1 does not provide an exhaustive description of the earth’s earliest history over that first week of history. But we are told that God brought the earth into existence at the beginning of Day One when He also began time and space (Genesis 1:1–2). And it was only on Day Four that God created the Sun, Moon, other planets—thus the solar system and asteroids, and the stars and galaxies (Genesis 1:14–19). By then the earth was internally stable with land and ocean areas on its surface, and the land was covered with soils, and plants growing in them (Genesis 1:9–13).

So the core, mantle, and crust divisions within the earth most likely would have been already in place on Day One, well before the Sun and the rest of the solar system were created. Any large or small bodies such as asteroids which impacted the earth and the Moon leaving the craters we see today could not have done so before Day Four or later. Thus they could not have contributed any significant quantities of material to the earth’s mantle. By Day Four the earth’s vegetated land surface and ocean waters were stable and pleasant for life to thrive on and in. Therefore, the mantle was stable and the compositional domains within it were there as part of the way God had created the earth.

We can thus dogmatically assert, based on the Word of God who cannot lie (Titus 1:2), that the evolutionary story of the earth condensing from matter flung out of the solar nebula over 4.5 billion years ago, which then condensed and differentiated into the metallic core and rocky mantle over millions of years, is absolutely wrong. Nor did impacting bodies from space accrete material contributions to the earth’s mantle to produce the domains within it. God had completed His Creation of the universe by the end of Day Six and pronounced it all “very good” (Genesis 1:31–2:1).

The mantle was stable and the compositional domains within it were there as part of the way God had created the earth, likely on Day One.

Therefore, once again, the mantle was stable and the compositional domains within it were there as part of the way God had created the earth, likely on Day One. Thus it can be argued dogmatically that the isotopic compositions of such mantle domains have nothing to do with their supposed ages according to radioactive decay. Those compositional domains were created by God already with that isotopic endowment, and the W, Pb, and other isotopes initially in them (which today are derived by radioactive decay) back then had not been derived via radioactive decay. The same argument has been advanced with respect to the isotopic compositions from which the claimed 4.567-billion-year radioisotope ages for the meteorites and their parent asteroids have been derived.14

Subsequently, during the Flood about 1,650 years or so after the Creation Week, mantle plumes rose to break apart the earth’s crust and initiate catastrophic plate tectonics.15 Those humungous outpourings of basalt lavas that erupted prodigiously from rising mantle plumes can thus truly be called Flood basalts! In fact, conventional slow-and-gradual plate tectonics has great difficulty explaining how such humungous volumes of basalt lavas could be erupted in what even in their millions-of-years timescale is but a veritable geologic instant. Instead, catastrophic plate tectonics during the year of the globe-engulfing Flood cataclysm explains admirably these flood basalts. The high ¹⁸²W/¹⁸⁴W ratios these Baffin Island and Java Ontong Plateau flood basalts contain are merely an indication that the mantle plumes responsible for these humungous catastrophic outpourings originated in domains at the base of the mantle with the high ¹⁸²W/¹⁸⁴W ratios that they were endowed with at the time the earth and its core and mantle were created only some 6,000 or so years ago.

Actually, the major puzzle for evolutionary geologists is how these mantle domains with high¹⁸²W/¹⁸⁴W ratios could have survived intact for so long through more than their 4 billion years of supposed earth history. After all, they also postulate melting and stirring of the mantle, and the formation and building from it of the earth’s crust over those billions of years after those mantle domains supposedly formed via the described scenario. Even according to their own purported story of that subsequent earth history, those mantle domains should long ago have been mixed and merged into other parts of the mantle, and even into the molten rocks that intruded into and erupted onto the ancient crust to build it.

On the other hand, the survival of these distinctive mantle domains with high ¹⁸²W/¹⁸⁴W ratios makes better sense in, and is more consistent with, the biblical framework of earth history. In that biblical framework, witnessed and given to us by the Creator Himself, those mantle domains only had to survive intact for some 1,650 or so years from when they were created until the Flood. And we can measure the isotopic compositions of these particular flood basalts today because they only erupted catastrophically some 4,500 or so years ago.

Conclusion

So does the earth’s mantle preserve chemical fingerprints of its origin? Absolutely, yes! But it is an origin from the hand of the Creator God, who put those chemical fingerprints in the mantle when He created the earth at the dawn of time and history only some 6,000 or so years ago. And that is exactly why those chemical fingerprints have survived and been preserved, because the earth’s origin was not from coalescing matter flung out from some solar nebula some 4.5 or so billion years ago! Furthermore, we can measure those chemical fingerprints today due to their having been preserved in these particular flood basalt lavas, because they were catastrophically erupted in humungous outpourings during the globe-engulfing Flood cataclysm only 4,500 or so years ago.