September 4, 2018 | David F. Coppedge

Two Geological Process Ages Collapse

Two processes theoretically assumed to take long ages have been shown they can occur quickly.

Over the years, we have reported several assumed long-age processes collapse by orders of magnitude (e.g., 19 Aug 2014, about stalactites, crystals and canyons; 20 December 2013 about crude oil made in one hour;  1 Nov 2012 about volcano dates being 3,000% wrong; and other examples under the topic Dating Methods). These re-evaluations illustrate twin dangers: the fallacy of extrapolating present processes carelessly into the unobservable past, and modeling that fails to take into account all the pertinent inputs. Here are two more recent examples.

1. The Carbon Cycle

Sulfur can lock up carbon in sediments, where it is preserved.

Faster than we thought: sulfurization of organic material (Washington University at St Louis). The subtitle reads, “New research is changing our understanding of the carbon cycle.” A process called “organic matter sulfurization” is the next candidate to fall from long age assumptions. Geologists had thought that a massive amount of carbon had been buried in the ocean 94 million years ago, leading to a massive change in climate. This carbon burial process took half a million years, they thought.

The basic assumption has been that some combination of super-giant algae blooms and low levels of oxygen in the ocean allowed the organic carbon from these blooms to be preserved in sediments.

New research from the Department of Earth and Planetary Sciences in Arts & Sciences at Washington University in St. Louis shows that there is another process by which this carbon was preserved. Organic matter sulfurization — which previously had been thought to act over timescales of tens of thousands of years — can actually occur much faster, according to research published this week in the journal Nature Communications.

So how much faster can it occur, according to the new thinking? “Organic matter sulfurization reactions can occur on the timescale of just hours to days,” according to the press release and the open-access paper. That’s a speed-up of six to seven orders of magnitude! “We can even induce them in 24 hours in the lab,” one assistant professor of earth science says.

This change in timescales may have sizable implications for how scientists understand the past and future of the Earth’s climate.

Now think about the implications. “This change in timescales may have sizable implications for how scientists understand the past and future of the Earth’s climate,” the press release says. Does the IPCC realize that?

The researchers do not question the standard assumptions about millions of years of earth history, and continue to believe some of their assumptions about climate are correct. But they have uncovered a process that before now was missing from climate models. More than climate-change science could be affected by this collapsing timescale for carbon sulfurization:

The potential widespread nature of sulfurization as a manner of carbon preservation means that our understanding of the history of oxygen in the ocean may need to be reevaluated.

Undoubtedly, many papers in the process of publication did not take this into account. And because of educational inertia, the new finding may not become widely known for years. Textbooks do not get re-written quickly. The political fallout from bad model inputs may not be seen before important decisions are made.

2. Seafloor Topography

Modelling shows what causes abyssal hills 2.5km below sea level (Phys.org). Much of the seafloor is not flat, but is punctuated by hills and valleys – some quite steep. How did they form? A leading “sensational” idea has been that they reflect changes in earth climate driven by earth’s orbital cycles over millions of years. But despite their bravado, scientists still know little about seafloor topography.

Half a century after discovering how plate tectonics works, the deep ocean floor is still a mystery to us. Why is the seafloor a vast expanse of hills and valleys?

A sensational hypothesis suggested that climate and sea level cycles directly drive magma generation and the rolling hills of seafloor topography. But computer models of volcanism and faulting at mid-ocean ridges lead to the view that crustal faulting forms seafloor “abyssal hills.”

The climate-cycle theory ties into the Milankovitch Theory (see 22 June 2018, “Why Milankovitch Theory Is Like Astrology”). which supposes that long-age cycles are driven by orbital dynamics of the earth around the sun, which are slow and gradual. Scientists at the University of Sydney evaluated the competing models (climate-driven cycles vs volcanism and faulting). The latter won hands down:

The verdict: there is no sign of climate and sea-level fluctuations playing any role – instead, crustal faulting primarily drives the formation of abyssal hills.

Their paper in Geophysical Research Letters indicates a big collapse in timescales: “No evidence for Milankovitch cycle influence on abyssal hills at intermediate, fast and super‐fast spreading rates.” The paper basically unlinks seafloor topography from crustal age, and in the process, scores another hit against Milankovitch theory. “Our results do not support the presence of Milankovitch‐driven signals in abyssal hill topography,” they say.

Clearly, crustal faulting does not require long ages, either. Although the press release does not state how fast the authors think abyssal hills can form, there is no reason to assume they require slow, gradual processes.

We think people should learn about the viscosity of the quicksand upon which many geological theories are built.

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