The Design of the Cosmos Part 8: Plate Tectonics - God's Shake N Bake Recipe for Life

I've been awol from my blog for a while, but I've got a few minutes tonight to finally get to my post on plate tectonics. I also wanted to tell you that I finally finished grad school and my MBA is mine! Awesome to be done but it was great to study and learn and interact with great professors at UGC.

I never knew this before, but did you know that the Earth would be a water world today were it not for fine tuned plate tectonic activity and vulcanism? If not for powerful and sustained (and finely tuned) plate tectonics, water would have covered the entire surface of the Earth removing a habital zone for we human beings. Advanced civilization would not therefore be possible without precise plate tectontic activity in the early Earth.

Remember on my last post on Earth's Oxygenation events how the cyanobacteria played a huge part in preparing the Earth for more advanced life later on by helping to oxygenate the Earth while helping to reduce the greenhouse gases forming in Earth's atmosphere as the Sun increased in luminosity? Well, these cryptogamic colonies of bacteria chemically conditioned the soil of the newly formed landmasses which appeared as plate tectonic activity increased (more about this later) on the early Earth. These early land masses were both hot and soil-deficient, but these colonies helped transform the soil into nutrient rich landmasses which the vascular plants needed to proliferate the Earth. These colonies also cooled the environment and oxygenated the atmosphere (see my previous blog entry on Earth's Great Oxygenation Events).

It took 2 to 3 billion years of this cryptogamic activity to condition the soil and oxygenate the atmoshphere to prepare the Earth for more advanced life. This tells of careful planning by a creator.

From Hugh Ross's book, "More than a Theory" here's why:

"Though cryptogamic colonies needed only a few small islands to survive, advanced life needed continents. A combination of both continents and large oceans were also necessary for regulating Earth's surface and atmosphere to compensate for the Sun's increasing brightness. However, continents were not a given. Continents formed out of light silicate rocks that 'floated' above the denser basaltic rocks comprising ocean floors. The separation of Earth's primordial crust into silicates and basalts occurred through the dynamics of crustal plate pressures and movements.

Stable, long standing plate tectonics required three things: (1) a powerful, long lasting source of radioactive decay in Earth's interior, (2) a stable efficient dynamo (electric generator) in Earth's core, and (3) an abundant supply of liquid water on Earth's surface. Each of these essentials had to exist at a precisely fine-tuned level.

For example, an abundance of long-lived radioactive elements requires (among other things) a concert of highly unlikely, perfectly timed and placed supernova events, as well as the amazingly fine-tuned collision that formed the Moon. (see my previous blog entry on the Moon) The stability and efficiency of Earth's dynamo depends on the exact regulation of at least seven major geophysical features." page 154.

Let me help unpack each of these three requirements for long standing plate tectonics for you:

1) A powerful, long lasting source of radioactive decay in Earth's interior: When certain elements undergo radioactive decay, energy is released providing heat. This heat was the catalyst that generated convective cells throughout Earth's mantle, and thus began the process of continent building. The cells are like large eddies that circulate in the Earth's mantle from just under the Earth's crust to just above it's core. Things get a bit technical here, so let me have Dr. Ross explain further:

"Different eddies associate with different crust regions. At the boundaries of these regions, subduction (the sliding of one crustal plate under another) can occur, but only if a huge amount of high density, low temperature liquid water was available to lubricate the sliding. Subduction is governed by the rate at which minerals in the area where two underwater plates come together (the subduction zone) chemically react with water to form hydrated minerals. The hydration process in the downward moving slabs leads to production of a talc layer that reduces and stabilizes the sliding friction between adjoining plates. A just right level of lubrication permits efficient movement of one tectonic plate under another. At these subduction zones, some basaltic slabs become hydrated. This lowers the newly hydrated minerals' melting point. Once enough of these silicates began to float above the nonhydrated basalts, Earth's mountains and continents began forming. Given their lower melting point, the silicates stayed liquid at depths closer to the surface, thereby facilitating the formation of volcanoes. The ongoing development of mountains and volcanoes resulted in landmasses poking up above the water's surface. With yet more time, these landmasses grew to become continents. However, they had to continue growing at the just right rates througout life's history for the Sun's increasing luminosity (see my previous blog entry on the Sun) to be properly compensated." page 155

If I may sum up, here's the kicker: As the Sun increases in luminosity, greenhouse gases build up in Earth's atmosphere, meaning that for there to be any hope of removing enough of these greenhouse gases from the atmosphere, continental landmasses must buildup through plate tectonic activity at such a rate as to exceed and later keep up with the reduction of continental land masses through the process of erosion. However, because radioactive decay energy release decreases over time, this would mean that erosion rates might exceed continental buildup rates, meaning that these greenhouse gases would stifle any advance life forms from filling the Earth.

Seems like a dilemma for advanced life, doesn't it? Not for the Creator. Remember from my previous blog on the moon that due to it's large size and position relative to the Earth, the Moon acts as a tidal brake on the rotation rate of the Earth. A slower rotation rate would mean less erosion, and thus the problem of the decline in the rate of continent buildup over time was accompanied by a decline in the rate of continent erosion. This timing is truly of the miraculous.

2) A stable, efficient, dynamo:

Dr. Ross goes on to describe these seven features of the Earth's dynamo. Let me briefly describe them for you:

1. Relative abundances of silicon, iron, and sulfur in Earth's solid inner core.

2. Viscosities at the boundaries between this solid inner core and the liquid outer core and between the liquid outer core and the mantle.

3. Ratio of Earth's inner core to outer core radii.

4. Ratio of the inner core to outer core magnetic diffusivity (measure of how well a magnetic field diffuses throughout a conducting medium)

5. Magnetic Reynolds number (a measure of viscous flow behavior) for the outer core.

6. Gravitational torques from the Sun and Moon

7. Earth's core precession frequency

3) An abundant supply of water covering the Earth (see my previous blogs - bible passages referring to water covering the early Earth)

Without plate tectonics, we'd have no place to live because there would only be water and because we'd be all boiled to death by the trapped greenhouse gases in our atmosphere which plate tectonic activity would have otherwise helped to dissipate. Read what Dr. Jeff Zweerink has to say to help sum things up in his article: Evidence of Early Plate Tectonics and also Fine Tuning Allows Essential Plate Tectonics to Take Off.

Also, without the decreasing energy release over time from radioactive decay rates, we'd also be experiencing far more frequent and devastating earthquakes than we do today, such that advanced life would not be possible.

Here's a great passage on the subject from the Bible in Psalm 104:

5 He set the earth on its foundations; it can never be moved.
6 You covered it with the deep as with a garment; the waters stood above the mountains.
7 But at your rebuke the waters fled, at the sound of your thunder they took to flight;
8 they flowed over the mountains, they went down into the valleys, to the place you assigned for them.
9 You set a boundary they cannot cross; never again will they cover the earth.

It truly is amazing to look at the mountains. Without them we would not be here.

Cheers until next time

Tom