After decades of telling the public comets brought Earth’s water, scientists are giving up on the idea. It was volcanoes, now they say.
A geologist and mineralogist from Trinity College Dublin says that “Scientists are changing their minds about how the Earth’s water got here.” Writing on The Conversation, Balz Kamber points to evidences that go against the special-delivery theory (what we have called the “water balloon theory”, 7/23/12) for the origin of Earth’s water.
- The isotope of ruthenium found on Earth’s surface is the wrong type to have come from the outer solar system. Ruthenium, a siderophile (iron-loving) element, should have been dragged with iron into Earth’s core. This suggested to geophysicists in the 1970s that it was delivered by comets and asteroids in a “late veneer” after the Earth differentiated, leaving water on the surface as a by-product. But if the impactors were from the inner solar system, they would have been too dry.
- Zircons, thought to have been formed 4.3 billion years ago, appear to have been in contact with water some 200- to 400-million Darwin Years before the “late veneer” should have formed.
- The heat of impacts may have obliterated water as much as delivered it.
- The presence of chlorine implies that it had water to dissolve into – otherwise it would have been lost to space.
If water was on Earth early on, it must have already been here at the time of formation. How could that be on a molten world rife with volcanoes? According to Kamber, volcanoes were the answer. They spewed up minerals that contained hydroxyl ions (OH–) which recombined into H2O as the minerals crystallized. Cute theory; does it work?
But it is important to understand that water can also be recycled back into the mantle. This means there is a balance between the water in the oceans and that stored up in the mantle. We can only speculate how much water might still be locked up at these great depths.
What we do know is that the average level of the sea surface relative to the continental land has remained relatively constant across nearly four billion years. This suggests a constant cycle of water emerging from and being absorbed back into the mantle has significantly helped life to continue throughout its history on this planet.
How, though, would the current levels be established? If the rates are balanced, any water erupted would have sunk back into the mantle just as quickly. Is he sure that volatiles will collect on the surface instead of being lost to space, before an ozone layer protected the surface from ultraviolet rays? Why don’t we see oceans forming around volcanoes today? Kamber seems to invoke special pleading to come up with a 70% watery surface that has “significantly helped life” since its inception. Does this improve on luck or miracles?
A bigger issue is the demise of a theory after over 40 years of propaganda. Learning that lesson, what confidence can anyone have that the inside-out theory will survive the next 40 years?
Not all water is just water. It has properties, such as acidity. The deuterium ratio, not mentioned by Kamber, was another blow to the water-balloon theory. A paper in Science discusses “The geologic history of seawater pH.” Here’s the editors’ summary:
The acid-base balance of the oceans has been critical in maintaining Earth’s habitability and allowing the emergence of early life. Despite this importance, systematic estimates of historical seawater pH are lacking. Halevy and Bachan developed a model of seawater chemistry and pH over time scales exceeding ∼100 million years. Their highly robust probabilistic history of seawater pH and chemistry reflects evolving properties of Earth’s atmosphere, oceans, and crust. Seawater pH increased from early Archean values of ∼6.5 to 7.0 to more recent values of ∼7.5 to 9.0 mostly as a result of solar brightening and decreasing interaction between seawater and oceanic crust.
What they mean is that the model is robust within its own assumptions, not that it connects with the real world. There’s no way they could know such things. All they know is that there is a constraint that the water’s acidity be survivable over the history of life on Earth from the beginning, “allowing the emergence of early life.” Note to the authors: emergence is a miracle word (see Poof Spoof), and pH constrains life— it doesn’t “allow” it. Otherwise it’s like saying that the existence of air “allows” birds to emerge and fly.
Secular materialists have been oscillating between the water-balloon theory and the volcano theory for decades, for centuries, since Laplace famously said he had no need of that [God] hypothesis. Well, are they making progress? They’re like witless gamers shuffling cups around on the table trying to figure out which one has the marble under it. They lift a cup once in awhile, find out there’s no marble, and think, “It must be under the other one.” Shuffle some more; try again. This goes on for centuries. How about the hypothesis that there is no marble – i.e., there is no secular theory that works?
What’s clear from these two papers is that life requires water from the beginning. Strange; that’s what the Bible says happened.