Issues with the Session’s Universal Model
The following are posts written by Barry Bickmore. A Geology professor from BYU. (I took a mineralogy class from him, his very first year of teaching, and can personally attest to his awesome character and intellect). I reproduce them here in case his blog disappears, and because they are kind of hard to find on his blog so I like to have them all on one page thats easy for me to wade through and outline. See his blog, called ‘Climate Asylum’ at this link.
[add a personal note, add ward radio video and disclaimer. Add my comment from it.]The Mass of the Earth is a MASSIVE PROBLEM for the Universal Model
This is part of a series of articles responding to the claims made in Dean Sessions’ Universal Model. Click the link to see the introduction to the series.
UM Claim: The Universal Model claims that instead of a core made mostly of iron, the Earth has a core made of ice. But if so, that would mean the Earth has a much different total mass than scientists believe, and all the standard measurements of Isaac Newton’s Universal Gravitational Constant (G), starting with Henry Cavendish’s torsion balance experiment in 1798, must have been wildly inaccurate.
One of the indirect evidences used in determining the Earth’s core composition is density. From where did the inferred average density of 5.52 g/cm^3 come? The answer comes from one experiment described in subchapter 18.4 [not yet published], the Cavendish Experiment. In 1798, Henry Cavendish constructed an apparatus similar to a pendulum but designed to measure the faint gravitational attraction between two large lead balls and two small lead balls. The two sets of balls suspended independently allowed Cavendish to obtain accurate measurements of the twisting suspension wire as the balls oscillated back and forth past each other. The whole process of this experiment, fascinating as it is, gets duplicated and retested by others in physics labs today. However, there is one major flaw in the experiment leading to the Cavendish Error. Unlike the Earth, the lead balls are not in outer space, and thus, the balls, restricted by the air and influenced by the Earth’s gravity rendered incorrect data. Their attraction should have been measured in a vacuum, in low gravity. Air, a denser medium than the vacuum of space, along with the attractive gravitational force of the Earth, slowed the balls’ oscillation rate. Cavendish neglected to account for the reduced oscillation in the original experiment, leading to an incorrect gravitational constant and errors in the Earth’s density estimates.
As we will learn in subchapter 18.4, the New Mass of the Earth, the Earth’s density, recalculated to approximately 2.3 g/cm^3 using the physics of gravitational attraction and the new geological discoveries outlined in this and other chapters, renders a truer density of the Earth that aligns with empirical observations. We next examine the geological nature of the Earth’s density. (Universal Model, Vol. 1, p. 107)
Issue: Way back in 1798, Cavendish’s careful experiments implied a value of G = 6.754×10−11 m^3 kg^−1 s^−2, which is within about 1% of the accepted value today. And guess what? Dean Sessions wasn’t the first one to wonder whether air resistance affects these measurements. So not only have Cavendish-type experiments been done many times in a vacuum–they have also been done in both a vacuum AND during freefall to negate the effects of gravity! Many, many experiments have yielded about the same value for G, whether or not such corrections are made.
There probably have been experiments done that yielded wildly different values of G, but as Dean Sessions pointed out, rigorous experiments are hard to do, and lots of things can go wrong! If things could go wrong with the Cavendish experiment, why couldn’t they have gone wrong with whatever experiment Sessions set up in his garage? Replication of important experimental results is a hallmark of science, and the vast, vast majority of G measurements have been very close to one another.
When this point was made on the UM internet forum, the UM team eventually responded with this stunning admission.
The “appreciable effect on the pendulum” stated by Carter in regards to UM experimentation was a faulty test of a continuing experiment that will not be finished until the release of the Universal System – Volume III of the Universal Model.
That’s right. After the publication of Volume 1, the UM team found out that their garage experiment was faulty, but they seem quite confident that by the time they roll out Volume 3, they will get the result they need to save their model.
To be blunt, if the accepted value of G is even remotely accurate, there is no way the UM “hydroplanet” model can be right, or even in the ballpark.
One portion of the “discoveries” part of the Universal Model website states, “the concept that Earth is a Hydroplanet instead of a magmaplanet is one of the key components of the UM.” It also includes a fancy illustration (below) depicting what that means—you’ll notice that the Earth is depicted with a liquid water outer core and solid ice inner core:
On the other hand, the scientific consensus is that the outer and inner cores of the Earth are mostly liquid and solid iron—something more like this:
Iron is much denser than any known phase of H2O, so Sessions’ “hydroplanet” belief requires that the overall density and mass of the Earth be considerably reduced in order to fit his model. Without any empirical or mathematical basis, he confidently asserts that the Earth’s new mass is roughly 1/3 the actual mass that modern physics dictates.
His arguments rapidly fell apart when asked about the major problems a new mass of the Earth poses to orbital mechanics (I was a little encouraged, personally, to hear that he doesn’t dismiss satellites as a government hoax). And Dr. Barry Bickmore extensively covers Sessions’ false claims about the Earth’s mass in this blog post.
A few weeks ago, I had the opportunity to speak over the phone with Jarom Sessions (Dean’s son) about this issue, and he hung up on me as soon as I started into the particulars about the Earth’s mass. Russ Barlow (one of Sessions’ closest UM associates) called me later that evening, and he also could not offer any viable explanation for orbiting satellites under the current UM model except to repeat that Volume III of the Universal Model would somehow explain the discrepancy. I have learned that the repeated answer you will get from any die-hard UMer is this: “It will all be cleared up in Volume III.” If you don’t believe me, call them up and ask.
But…they haven’t released Volume III yet, so we will have to take it on faith that they will be able to rework modern physics to fit their claim (I guess starting with conclusions and working backwards is the new science). However, my bet is that Sessions cannot provide the mathematics necessary to prove his biased, ill-conceived conclusions.
Actually, I believe that Dean Sessions will, at some point in his life, come to the realization that the Earth’s mass has already been correctly described with modern physics. It’s pretty hard to argue against the simple reality that each new satellite we put into orbit stays there as a testament to the fact that we already know, reliably well, the Earth’s actual mass. They wouldn’t be in that orbital sweet spot if this weren’t true.
When Sessions and his followers finally do admit the Earth’s mass is already correct, I am confident that their next step will be to make something akin to this argument: The mantle must be much denser than is generally thought. That’s the only way to maintain our “hydroplanet” model and acknowledge that the Earth’s mass is already correct because…THERE MUST BE A WATER CORE!
I am confident this will be their eventual reaction because another (former?) UMer that I spoke with acknowledged to me that Sessions was wrong about the Earth’s mass and brought this same hypothesis up to me instead.
But I want to preemptively stop that line of reasoning before more UMers jump on that ill-judged train. The problem is that any “hydroplanet” model (I think of it as the “core(s)-light” model for obvious reasons) completely ignores the Earth’s moment of inertia factor, a useful clue to what the interior structure of any spinning sphere is.
In general, moment of inertia is just a measure of how hard it is to get something rotating. More precisely, according to merriam-webster, it can be defined as “a measure of the resistance of a body to angular acceleration about a given axis that is equal to the sum of the products of each element of mass in the body and the square of the element’s distance from the axis.” In mathematical terms, for a rigid sphere with a uniform density, then I=0.4mr^2 (where I is the moment of inertia, m is the mass, and r is the radius).
Moment of inertia demonstration with objects of same mass. Note that the red sphere is hollow.
Moment of inertia factor is related to moment of inertia and is used to describe the radial density distribution of all major planetary bodies in our solar system based on their spin precession, gravity quantities, mass, and radius. This PowerPoint by Francis Nimmo gives a detailed explanation of what moment of inertia factor is and how it’s calculated.
Generally put, if a celestial sphere has a moment of inertia factor less than 0.4, then its mass must be distributed more towards its core, and it will be denser at its core. If it has a moment of inertia factor greater than 0.4, then its mass must be distributed more towards its outer layers, and it will be denser toward its surface.
No planetary bodies (not even the moon) in our solar system have a moment of inertia factor greater than 0.4, meaning they are all denser towards their centers than they are towards their exteriors.
In fact, moment of inertia factor offers scientists a large clue about the interior makeup of nearly any nearby planetary body. Based on moment of inertia factors, we know that all major planetary bodies in our solar system have differentiated to some level, meaning that denser materials have sunk to their centers.
In short, the Earth’s inner and outer cores, which extend nearly halfway from its center, cannot be less dense than the Earth’s mantle. If this were true, then the Earth’s moment of inertia factor would be much higher. So, there is no core(s)-light model for the Earth, or really for any major planetary body in our solar system. The Sun and all the planets in our solar system are densest at their cores.
In Universal Model vol. 1, ch. 5, “The Magma Pseudotheory,” Dean Sessions is on a mission to disprove the existence of magma. (You can’t have a “hydroplanet” with a core of ice if it gets hotter toward the center.) To convince himself he has accomplished this, he performs his usual routine of misstating the actual scientific theory, disproving the fake theory he just made up, and then announcing that it all fits perfectly with the UM. No, it doesn’t. Oh, and he keeps forgetting about convection.
“Magma,” in geological parlance, means molten rock that exists below the Earth’s surface, whereas “lava” is the same thing after it is extruded out of a volcano. Dean Sessions knows about volcanoes, and he knows that lava must come from under the ground. So magma exists, right? Well, okay, but Sessions wants to make it clear that he doesn’t think molten rock forms below the crust of the Earth, so he renames “magma” in the crust as “intrusive lava”. Regular old “lava” becomes “extrusive lava.” The term “magma” he reserves for the “only… theoretical molten rock that geologists think is generated in the layers below the crust” (UM, vol. 1, p. 70).
Magma is a “pseudotheory,” according to Sessions, because pseudotheories are false theories taught as fact. It’s just a theory because we can’t drill holes down into the mantle and core of the Earth to directly examine what’s there. Instead, we just have to “infer” what’s there by indirect means. (You know, like we have to “infer” the existence of oxygen molecules by indirect means because we can’t shrink ourselves down small enough to look at them, and even if we could, our eyes wouldn’t work unless they were tuned to X-ray wavelengths, and so on.)
All Sessions has to do to show that deep magma is taught as a fact is to quote one geologist saying the opposite. “Magmas properly belong to the realm of theoretical petrology…. [T]hey cannot be examined in the field, collected, studied or directly experimented with” (UM, vol. 1, p. 71). Oh, wait! That wasn’t the part that proves Sessions’ point! It’s two pages later in the quoted text, where the geologist says, “There is, however, irrefutable direct evidence that materials with the physical properties of magma exist within the Earth.” See? How can there be direct evidence for magma if you can’t directly experiment with it? Oh, wait! Maybe the geologist was referring to the fact that we can detect substances that have the mechanical properties of molten rock by mapping how seismic waves travel through them. Or maybe he was referring to the fact that we can sometimes drill right down into an underground magma chamber, and find it there… you know… underground. I can hear the UM Team objecting that Dean Sessions knows quite well, thankyouverymuch, that molten rock exists in the crust (“intrusive lava”), but he was talking about “magma”–hypothetical molten rock below the crust. Of course, if the quoted geologist was using the standard geological definition of magma as “underground molten rock,” he really wasn’t contradicting himself. It’s only a problem if he was using the definition Dean Sessions made up.
Well, whatever. The MAIN point is that Dean Sessions can also quote a bunch of other geologists (pp. 70-71) carefully specifying that they don’t know everything about what’s in the deep Earth, which just goes to show that they don’t know anything, right?
But those pesky geologists persist in believing that they do know some things about the Earth’s deep interior, such as that it must be really hot down there. He quotes one geophysicist, “The interior of the Earth is clearly hotter than its surface, as shown by volcanoes and the temperatures within mine shafts” (p. 74). In other words, we know it must be hot down there because hot stuff comes shooting out the surface from time to time, and because when we dig holes it gets hotter as we go deeper.
Sessions claims he can prove the geologists wrong by doing what the scientists should have been doing all along–making sure scientific theories conform to actual observations, instead of just assuming their theories are true. Sessions points out, for instance, that the way heat escapes from the Earth is exactly the opposite of what the “Magma Pseudotheory” predicts, but it does follow what should be the case if the heat to melt rock is generated in the crust through frictional heating along faults, and kept going by tidal forces.
In reality, Dean Sessions just doesn’t understand what he’s talking about, and he is unable to recognize it when data do not conform to his ideas.
He begins on p. 92 by showing us a U.S. Geological Survey map of the thickness of the Earth’s crust, which clearly shows that the crust is much thicker on the continents than the ocean floor. He then uses the USGS map to make his own map of what the “Magma Pseudotheory” should predict, by assuming the heat flow through the thicker parts of the crust is less than through the thinner parts.
In the Magma Pseudotheory, heat coming from deep inside the Earth transfers to the surface through convection currents from the inner core toward the mantle and ultimately to the crust. It is then conducted to the surface, through the Crust. The flow of heat should be easily predicted and follow known patterns of heat transfer if the Earth’s heat is actually coming from magma. (p. 91)
Here’s how he explains the heat transfer theory he’s using.
The physics of heat flow tell us that heat travels or flows across a gradient from hot to cold and that the flow will be greater when the gradient is steeper. In other words, more heat flows from hot toward cold than flows from hot toward warm. The bottom of the ocean, at around 2 °C(35 °F) is much cooler than the surface of the continents, which averages approximately 14 °C (57 °F). Because of this, we should expect heat flow to be greater through the oceanic crust than through continental crust. Note that we are not referring to why the surface of the Earth is warmer than the bottom of the ocean-that is primarily due to solar heating. We are considering the flow of heat through the crust. (p. 92)
However, Sessions also produces (p. 92) another USGS Map showing actual measured heat flows around the globe (see below), and announces that they are totally different.
The greatest concentration[s] of heat… land on plate boundaries where gravitational frictional heating is highest…. This demonstrates unequivocally that the Earth’s heat flow through the crust cannot originate from a theoretical magma heat source beneath the crust, confirming the Frictional Heat Law and the Gravitational Friction Law. (p. 92)
Well, actually… if you look at the “actual heat flow” map, it’s clear that the highest flows are not at all plate boundaries. (Many plate boundaries appear to have quite low heat flows.) Rather they are at mid-ocean ridges, which are only one kind of plate boundary. These plate boundaries are where real plate tectonic theory (as opposed to the Magma Pseudotheory, whatever that is) says hot, plastic, solid material (NOT MAGMA) wells up from below in convection currents, pulling apart the overlying lithospheric plates. When the overlying lithosphere cracks apart like that, it lowers the pressure on the rocks below in the mantle, lowering their melting temperatures, so that some minerals melt and the magma creeps up through the cracks. So in reality, divergent plate boundaries are EXACTLY where conventional plate tectonic theory implies the greatest heat flow should be, because of convective heat transfer.
When Sessions used his simple conversion of crustal thickness to expected heat flow, he had to implicitly assume that the material below the crust has a uniform temperature all around the globe, and that no hot material is transported up through the crust. In other words, he must have forgotten that he just said the hot material was supposed to be transported around the interior in convection currents. In convection currents, hot material flows upward in certain places because it is less dense than the overlying cooler stuff. When it reaches the top it spreads out to the sides and cools, while the cooler stuff at the top sinks down to the bottom and heats up. This goes on over and over, as illustrated in this animation.
Geophysicists have not been able to explain why heat flow through the thin oceanic crust is less than the heat flow through the thick continental crust. The thicker and more insulated continental crust areas should have a significantly lower amount of heat flow whereas the thicker continental crust should theoretically be cooler than oceanic crust because of the distance from the heat source as predicted within magma theory. (p. 92)
Wait… look at that figure again. On average, at least, the ocean floors do show higher heat flow than the continents, and in fact geophysicists estimate that the average heat flow from the continental crust is 65 mW/m^2, whereas the average heat flow from oceanic crust is 101 mW/m^2. Why is Sessions now saying that there is less heat flow through the oceanic crust?
Sessions explains on p. 93 that since the continental crust is about six times as thick as the oceanic crust, then the heat flow through the oceanic crust should be six times higher. Conductive heat transfer is proportional to the thermal gradient (how much the temperature changes with depth) and the thermal conductivity of the material (how efficiently the material transmits heat by conduction), so assuming that the thermal conductivities of the oceanic and continental crust aren’t that different, the thermal gradient in the ocean crust should be steeper than that in the continental crust. Next Sessions produces a quotation from an old Scientific American article saying that the thermal gradient in the ocean crust is about 15 °C/km depth, whereas that of the continental crust is about 25 °C/km, which is seemingly the opposite of what we would expect.
The answer to this conundrum is, once again, that Dean Sessions forgot about convection.
The oceanic crust is under the ocean, after all, so lots of water gets down in the rocks and is heated up, causing convective flow. (NOTE: Even Sessions agrees that it gets hotter with depth within the crust, so this should not be controversial.) This hydrothermal flow actually increases the heat flow out of the interior, but simultaneously decreases the thermal gradient of the upper oceanic crust. In a convection current, hot stuff does flow toward the cooler areas, but cool stuff also flows toward the hotter areas, so the relationship between the thermal gradient and the heat flow is more complicated than with heat conduction.
Heat flow estimates like those plotted in the figure above are not measured directly. They are measured indirectly via thermal gradients. If essentially only heat conduction is going on (like in most of the continental crust), then you can just measure the thermal gradient in boreholes, estimate the thermal conductivity of the rocks, and back out the heat flow. If you know hydrothermal convection is going on, then you have to make corrections for that. And geophysicists do.
So now it all makes sense through the lens of standard plate tectonic theory, even if we don’t have all the details worked out. There is greater heat flow through the oceanic crust than the continental crust because ocean crust is thinner, because hot material is welling up at mid-ocean ridges, AND because of hydrothermal circulation under the ocean floor. The thermal gradient in oceanic crust is lower than that in continental crust because hydrothermal circulation also reduces this gradient, while increasing heat flow.
Does it make sense within the UM? Not really. The UM predicts that you should have high heat flow at all kinds of plate boundaries, because the heat is generated by earthquakes. So why don’t we see excess heat flow in areas where tectonic plates are causing continental lithosphere to collide (like in the Himalayas)? There are lots of earthquakes there, after all.
In fact, Sessions is beset by the same problems as regular scientists. That is, we can’t drill all the way to the center of the Earth to see what’s there. So why should we believe that the Earth is cold in the center (as in the UM), when from what we CAN see it gets hotter and hotter toward the center?
Get ready for it…
Sessions says (p. 94) that the Earth appears to heat up too rapidly with depth. He quotes a geophysicist from the 1930’s saying that “If the gradient determined [near the surface] should continue downward unchanged, the temperature at the center would exceed 350,000° F” (p. 94). Sessions then goes on:
No one thinks the center of Earth is thousands of times hotter than the surface of the Sun. How can heat be so high in the crust and still be thousands of kilometers from the source of heat, residing at or near the core? This too-hot-too-fast problem just does not follow the physics of heat flow. We would likely boil away if the Earth’s geotherm followed the assumed gradient of the magma model pseudotheory. A temperature of 350,000″F at the core just does not work for any theory! (pp. 94-95)
This objection would be correct… if convection were not going on in the mantle. That’s right. He forgot about convection again. Remember how you can actually get more heat flow through convection, with a lower thermal gradient, than when there is only thermal conduction? Once again, Sessions has disproved a prediction the standard theory does not actually make. Here is what the temperature profile of the Earth is supposed to look like according to the standard theory. Note how the gradient is lower in places like the atmosphere, mantle, and outer core, where lots of convection is supposed to be going on.
There’s really nothing left of the UM argument. Oh, maybe some geophysicists didn’t get the thermal gradient they were expecting in the odd borehole somewhere, or whatever, but that doesn’t cancel out the thousands upon thousands of other measurements that show steadily increasing temperature with depth. Sessions can complain all he wants about how geologists don’t know everything about the deep interior of the Earth (a fact geologists readily admit), but 1) he doesn’t either, and 2) none of the evidence that does exist supports his ideas.
Dean Sessions, author of the Universal Model, apparently thinks scientists are pretty stupid. The constant refrain in the UM is that scientists know there is all sorts of evidence that conflicts with their theories, but they just can’t imagine that their theories could possibly be wrong! My interpretation, however, is that Mr. Sessions is unable to understand how any particular observation conflicts with scientific theories, because he doesn’t understand the theories (and sometimes he doesn’t even understand the observations). The result is a sloppy string of out-of-context quotations and bizarre reasoning that brilliantly disproves all sorts of non-existent theories.
One case in point is his treatment of Plate Tectonics, the current unifying theory of geology. First, I will explain a few basics of the ACTUAL theory.
The ACTUAL Theory
In the theory of Plate Tectonics, the “plates” (rigid slabs of rock several km thick on the surface of the Earth) move around largely because of convection currents in the mantle (the layer below the crust).
Convection is the movement of heat energy with the material it inhabits. If you turn on the hot water faucet in your bathtub, for instance, heat energy in your water heater travels through the plumbing and into your tub because it travels with the flowing water.
Convection currents, or convection cells, move heat energy with some material in a more cyclical way. Think of a pot of water on a stove, where the heat is actually coming from the bottom. The water on the bottom heats up first, making it expand a little. Since it is less dense than the overlying cooler water, the warmer water floats upward and the cooler water sinks downward. Now the water on top is cooling off by releasing heat into the air, and the water on the bottom is heating up. Pretty soon the water on the bottom becomes warmer than that on the top, and they trade places again. This sets up a continuous cyclical motion.
To get convection currents, you need a source of heat on the bottom, and a way to release the heat at the top. You also need the convecting material to be some kind of fluid. Usually, when we think of fluids, we think of liquids and gases, neither of which hold their shapes when they are not held in a container. Solids are usually not considered fluids, but there are important cases where a material seems to behave like a cross between a solid and a liquid. Think of Play-Dough, for instance. It will keep its shape, but if you push on it with a finger, the shape is deformed. Instead of bouncing back to its original shape or breaking, like most things we think of as solids would, it keeps its new shape. If a solid behaves like this (i.e., it can squish around instead of cracking) then it can be moved around in slow-moving convection currents. Rock that is heated and pressurized (but not melted into a liquid) can behave this way.
Once upon a time, it was thought that the solid crust was floating on a big ocean of magma, but since the early 20th century it has been clear that most of the Earth is solid, the only liquid layer being the outer core. (We can tell because a certain type of seismic wave can only travel through solids.) So if the part of the mantle underneath the plates is essentially solid, it must be softened by the heat and pressure so it can be squished around in convection currents. These currents must move quite slowly, because plates only move laterally by a few centimeters per year.
Get it? The plates are “floating” on top of the softened, but still solid rock below, much like you “float”, or partially sink into, your bed when you lie down on it. (The bed is solid, but squishy.) There is no ocean of magma (melted or molten rock) underneath.
Oh, So He Does Understand!
At some points in the UM, it seems like Sessions does understand that the “magma ocean” theory is long gone.
Ideas change. Magma was once a new idea, and as it developed, geologists imagined a great ocean of magma deep inside the Earth: an all-encompassing body that supplied the heat and lava to all volcanoes, but that idea fell out of favor during the early 1900s. Quoting from a 1911 encyclopedia:
“The old idea of a universal magma, or continuous pyrosphere, has been generally abandoned….” (UM, Vol. 1, p. 76)
See? Right there in his book, Sessions tells us that it has been out of favor for over 100 years!
On the same page, it also seems clear that Sessions understands that the seismic wave evidence shows that only the outer core is liquid, even if he disagrees with scientists about what that liquid is.
Seismic waves do establish that a large portion of the interior of the Earth is liquid but it does not establish what that liquid is. A simple question one could ask is magma the only liquid found in Nature? The answer–no.
The geologists themselves state in the foregoing statement that they have only been able to “guess” what Liquid occupies the Earth’s underworld. Their research “implies a molten core” but they do not know this. They do know that there is a shadow zone caused by the liquid in the outer core of the Earth as illustrated in Fig 5.2.2. The shadow zone appears repeatedly, when earthquakes occur.
From the different magnitudes and arrival times of the different waves, researchers in the early twentieth century were able to develop a rough picture of the interior of the Earth. As technology improves, the picture is ever clearer, and one of the most convincing evidences that magma does not exist comes from an understanding about these seismic waves. (UM, Vol. 1, p. 76)
No… He Doesn’t Understand
But just a couple pages later, Sessions makes the following claim.
The plate tectonics theory proposes crustal movement based on convective magma, one facet of the magmaplanet model. (UM, Vol. 1, p. 78)
In another chapter, he emphasizes once again that he really does believe geologists think the plates are riding around on an ocean of magma. (He gets his information this time from… and I’m not kidding about this… a website called geography4kids.com.
It is important to note that modern geology already has empirical evidence establishing that the Earth’s Continents are floating. In fact, children are taught in grade school about floating plates, along with other not-so-proven concepts. Here is the website geography4kids.com, which explains how the Earth’s continental plates float:
“THEY REALLY FLOAT?”
“These plates make up the top layer of the Earth called the lithosphere. Directly under that layer is the asthenosphere. It’s a flowing area of molten rock. There is constant heat and radiation given off from the center of the Earth. That energy is what constantly heats the rocks and melts them. The tectonic plates are floating on top of the molten rock and moving around the planet.”
We previously discussed Earth’s continental plates and their observable movement of several centimeters per year (see Fig 15.13.1), but we have taken the position that there is no magma, and therefore, no molten rock upon which the plates ride, so we naturally have to ask; what are the plates floating on? This is a truly fundamental question. (UM, Vol. 1, p. 231)
Clearly, this is wrong, but why would Sessions cite some random geography (not even geology!) website for kids in the first place? He cites a number of real geology textbooks throughout the UM, after all. For example, Sessions refers several times to a book by O.M. Phillips, The Heart of the Earth, which was published in 1968, when the theory of Plate Tectonics was brand-spanking new. Here’s what Phillips said about the issue.
Before we can ascribe any significance to this suggestion [that mantle convection drives plate motion], though, it is necessary to be convinced that movements of this kind in the mantle are qualitatively or descriptively plausible and do not do violence to the observations already established.
The idea poses an immediate dilemma. Convection is a type of motion that can occur only in a fluid. yet the mantle is capable of transmitting S waves, and these cannot travel through a fluid. Furthermore, deep earthquakes occur frequently at depths between 80 and 300 km, sometimes as deep as 600 or 700 km, and sudden fracture or slipping does not occur in a fluid. These are serious objections; are they crippling? The answer, I believe, is no….
The simple classification of materials as solids, liquids and gases is convenient, but not particularly precise. Some, like water at ordinary temperatures, are unambiguously liquid. Others, like mayonnaise or the interior of a half-cooked cake are neither clearly solid nor clearly liquid…. This general type of behavior, in which the simple classification fails, is in fact very common; it is the rule rather than the exception, especially at the high temperatures that we expect to find in the earth’s mantle. Most metals and plastics certainly behave this way. They can be bent and squeezed into shape; they can be made to flow. (O.M. Phillips, The Heart of the Earth. Freeman, Cooper & Company, San Francisco, 1968, pp. 167-168)
Are you starting to get the picture? When researching for his magnum opus, Sessions seems to have combed through hundreds of books, articles, and websites, hand-picking quotations he thought he could fit into his narrative that scientists are dogmatic and confused, and ignoring anything that might have helped him understand what scientists actually think.
There are no “magma oceans” below the crust, and no geologists I know of have thought this for a very long time. And yet, Sessions puts quite a bit of effort into debunking this idea. Why?
In the Universal Model, Vol. 1, Dean Sessions says that if current scientific theories about the interior of the Earth (i.e., that it’s hotter down there) are correct, then we should see highly radioactive lava erupting from volcanoes. However, that’s beyond wrong–it’s ludicrous. Let me explain.
As noted in the UM, the standard theory is that the interior of the Earth was originally hot because of heat generated when the planet formed from the solar nebula (a cloud of space debris coalescing by gravity) around 4.5 billion years ago. Things smashing together, friction creating heat–you get the idea. The problem is that geologists figured out quite a while ago that if this “residual heat” were the only source, then the Earth should have completely cooled off a long time ago. An apparent solution was found when scientists discovered radioactivity. Certain elements (most notably uranium, thorium, and potassium) include isotopes (atoms of that element with different numbers of neutrons in their nuclei) whose nuclei can decay over time, creating atoms of different elements, releasing fractured nuclei and/or subatomic particles, and releasing heat. So here’s the logic.
“Hey, we need another source of heat to explain why the Earth’s interior is still hot!”
“Oh, look! We found out that some elements in the Earth are radioactive, and they produce heat! Maybe that’s it!”
Not too complicated, right? But Dean Sessions wants the core of the Earth to be a giant ice ball, so he tries to dismiss the idea that radioactivity could provide an explanation.
However, naturally occurring radioactive rocks are weak and generate very little heat. The most abundant, naturally occurring radioactive rock is uranium, which is found only near the surface of the Earth. Moreover, there are no known radioactive lava flows. (p. 97)
Let’s take that apart.
First, ALL rocks are radioactive. ALL OF THEM. All it takes to make a radioactive rock is a single radioactive atom, and with modern mass spectrometers, we can measure small amounts of radioactive atoms. And if a little heat is generated by every single radioactive decay event that occurs, then that heat can add up to quite a lot throughout the entire Earth.
Second, uranium is an element, not a “rock”. (Seriously, it’s like Sessions is trying to give rage aneurysms to geochemists.)
Third, it’s true that the most abundant radioactive isotopes tend to concentrate most in the crust of the Earth, but that really doesn’t matter. Suppose you have a sphere with heat sources spread throughout, but especially near the surface. Heat energy is generated, and spreads out. Some of it flows toward the surface and is radiated out into space, and some of it flows toward the center, because heat tends to flow, on average, in the direction of colder temperatures. When the heat energy gets to the center, where does it go? The only way to flow is toward the surface, but if the temperature is still warmer on the outside of the sphere, the net heat flow will still be toward the center. Therefore, the center will keep heating up until it is hotter than the outside of the sphere and heat can flow back the other way.
(Think about this, UMers. If the Earth is actually colder in the center, then there must be some kind of black hole sucking heat out of there.)
Fourth, geologists don’t think magma is generated in places where it is way hotter than other parts of the interior. Rather, magma is mostly generated in places where the local pressure, temperature, and composition favor melting. For example, in subduction zones, waterlogged oceanic crust gets shoved down into the mantle. Since water is KNOWN to lower the melting temperatures of many minerals (yes, this has been experimentally verified), the mantle rocks above the subducted crust will be more likely to melt when exposed to more water, and that’s how geologists explain the fact that lots of volcanoes occur above subduction zones. When the crust (lithosphere, actually) cracks open at a divergent plate boundary (mid-ocean ridges, mainly) that drops the pressure on the mantle rocks just below the crack. Since lowering the pressure is KNOWN to lower the melting temperatures of rocks, that’s how geologists explain the fact that there are lots of volcanoes at mid-ocean ridges.
So basically, the idea that lava should be more radioactive than other Earth materials if geologists are right about the interior of the Earth is nonsensical.
