Earth's 'boring billion' years of stagnant, stinking oceans might actually have been rather dynamic

Earth’s 'boring billion' years of stagnant, stinking oceans might actually have been rather dynamic
Lake Superior rocks from the ‘boring billion’. Credit: Burns Cheadle, CC BY-NC

Geologists have dubbed Earth's middle age the "boring billion." Occurring some 1,800 to 800 million years ago, it has long been considered a period when little happened on Earth in terms of biological evolution, climate, or the chemistry of the oceans and atmosphere. But emerging evidence now suggests that the "boring billion" may have been far more dynamic than that.

Our planet has been shaped by many monumental events. From the Cambrian explosion around 540 million years ago, when most animal forms appeared, to the rise and fall of the dinosaurs, the dramatic course of biological evolution is well documented by the fossil record. Similarly, from the glaciations of the most recent ice age, to much earlier "snowball Earth" periods, when the entire planet may have frozen over for millions of years, climate change has left a clear imprint on the geological record. But then we come to the "boring billion," where the rocks appear to give us startling evidence for, well, not much really.

At first glance, the Earth seems to have been stuck in perpetual stasis across this billion year interval. The planet was likely somewhat warmer than today, but there is zero evidence in the rocks for any dramatic change in climate. Oxygen in the atmosphere was stuck at a level much lower than we have today, and indeed much of the global was entirely devoid of , leading to inhospitable seas that were rich in either iron or toxic hydrogen sulphide (the smelly gas released by rotten eggs).

While the first eukaryotes (cells with a nucleus) had already evolved, the pace of biological evolution appeared to have stalled. Until recently, the most advanced traces of life found at any time through this interval were tiny organic microfossils in aquatic environments, and if you went back in time on safari, you would be confronted by entirely barren landscapes.

Earth’s 'boring billion' years of stagnant, stinking oceans might actually have been rather dynamic
Geologic clock: if Earth’s history is plotted over 12hrs, not much happened between about 7 and 10 o'clock. Credit: Woudloper / wiki, CC BY-SA

All of this led the ever-mischievous scientist Roger Buick, in a seminal 1995 publication, to paraphrase Winston Churchill with the immortal line "never in the course of Earth's history did so little happen to so much for so long." Apparently inspired, the late palaeontologist Martin Brasier then coined the term "boring billion," and it is this soundbite that has since become firmly embedded in geological consciousness.

But geologists have recently shown renewed interest in this (which forms part of what we call the Proterozoic Eon), and I would now argue that the "boring billion" is every bit as exciting and important to understand as anything that happened in the past 500m years of Earth history. If we do not understand periods of relative stasis, then what hope do we have for understanding times of monumental change?

Stinky oceans

So how does a scientist first get interested in all this? As is often the case, it happened almost by accident. While a Ph.D. student, I spent my time thinking about mud at the bottom of the modern ocean, which tends to be full of the toxic hydrogen sulphide mentioned above. At about the same time, Don Canfield of the University of Southern Denmark started writing about stagnant, stinking, hydrogen sulphide-rich oceans during the "boring billion." The idea captured my imagination.

Earth’s 'boring billion' years of stagnant, stinking oceans might actually have been rather dynamic
Fossil algae from 1.56 billion years ago. Credit: Zhu et al / Nature Communications

So, when an opportunity arose to work with Don I seized the moment and started to attack 1.8 billion year old rocks from the north shore of Lake Superior with some of the tools we were using to understand mud in the modern ocean. The results were cool—we did indeed find clear evidence for widespread stinking oceans devoid of oxygen.

But this was just the start. Since then it has become clear that were not static at all during the "boring billion," and in fact geologists have found for intervals of increased oxygen. (Why didn't this prompt evolution on the scale of the Cambrian? Partly because we are still talking about relatively low levels. But there's also huge argument among scientists over whether oxygen spurred early animal evolution, or whether the evolution of animals allowed oxygen levels to rise).

Paleontologists have also recently begun to identify a much richer tapestry of life across the interval, which includes an increase in the size of seaweed-like algae coincident with rising levels of oxygen. These fossils might not appear as dramatic as the early animals of the Cambrian explosion, but they provide a crucial window into the course of biological evolution on Earth, and help fuel the debate over the importance of oxygen in early .

Against the backdrop of these advances, it is also clear that we have only just begun to piece together the enigmatic history of this fascinating time period. We need to look at the rocks with new techniques and new eyes to unravel the subtle clues that they hide. Likewise, new locations housing spectacular fossils are sure to be found. It is fair to expect that in 10 or 20 years we will have a profoundly different perception of the so-called "boring billion."


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Alternatively, Venus may have been the cradle for multicellular life in the early solar system that contaminated Earth in the Cambrian Explosion, if Venus suffered a Venusian cataclysm (VC) when a former retrograde moon in a decaying orbit merged with the planet at 541 Ma.

- VC responsible for the retrograde rotation of Venus and its 'recent' resurfacing
- VC responsible for volcanic coronae and dense sulfur dioxide atmosphere, as the continued digestion of the former moon
- VC briefly fogged the inner solar system, causing the Baykonurian glaciation at the Proterozoic–Phanerozoic boundary.
- VC responsible for Cambrian Explosion, establishing all modern phyla on Earth

Jul 29, 2019
Alternatively, Venus may have been the cradle for multicellular life in the early solar system that contaminated Earth in the Cambrian Explosion, if Venus suffered a Venusian cataclysm (VC) when a former retrograde moon in a decaying orbit merged with the planet at 541 Ma.

Except that there's no evidence that such a cataclysm indeed happended.

- VC responsible for the retrograde rotation of Venus and its 'recent' resurfacing

Tidal torque could explain the very slow retrograde rotation of Venus without having to resort to an impact, which would have been massive enough to leave signs visible to a radar survey. Evidence suggests that resurfacing occurred in multiple events at different locations, which suggests volcanism as a cause rather than in impact.

To be continued...


Jul 29, 2019

- VC briefly fogged the inner solar system, causing the Baykonurian glaciation at the Proterozoic–Phanerozoic boundary.

That would have required a mass greater than Jupiter to be completely pulverized. Do you have any idea how huge the orbit of Venus is, let alone the entire inner solar system?
- VC responsible for Cambrian Explosion, establishing all modern phyla on Earth

Except that the algal cell fossils present before the Cambrian explosion look the same as the ones after. We may not have a clear understanding yet of how the Cambrian explosion occurred, but with life being present on Earth way before the Cambrian explosion, the chances are much higher that it didn't require external intervention. Besides, the scarcity of fossils (due to possibly bad conditions for preservation of multicellular fossils during the boring billions) before the Cambrian could create the illusion of an "explosion".

Jul 29, 2019
A rock falling from Mars would be much more likely to survive the trip with lifeforms intact versus a far more improbable journey of rocks being blasted off Venus and making it here with viable life. Hopefully, we will be able to find proof one way or another to verify if Earth life or parts of it were evolved elsewhere.

Tidal torque could explain the very slow retrograde rotation of Venus without having to resort to an impact, which would have been massive enough to leave signs visible to a radar survey. Evidence suggests that resurfacing occurred in multiple events at different locations, which suggests volcanism as a cause rather than in impact.


Tidal torque (by the sun) can NOT create retrograde rotation. At best it results in synchronous rotation, like Earth's Moon.

We live in a fractal and chaotic universe, which should include chaotic resurfacing of Venus following a moony merger.

This is a conceptual alternative, unsupported by calculation, which attempts to unify a handful of disparate phenomena in unsettled science. One of my greatest complaints about academic science is its over reliance on separate solutions for separate phenomena.

(continued)

VC is only a sliver of a more extensive alternative ideology that offers an origin story for the three sets of twin-binary planets in our solar system and a former binary-Companion to the sun (V-E, J-S, and U-N, former binary-Companion with super-jupiter-mass components), which suggests that each of these twin-binary sets was formed with an oversized 'Titan moon', half in prograde orbits (prograde Luna; prograde Titan; missing prograde moon at Uranus), and half in retrograde orbits (retrograde Triton; former retrograde moon at Venus, merged at 541 Ma; former moon at Jupiter, merged at 4,562 Ma condensing enstatite chondrites on the terrestrial fractionation line).

Grand tack (GT) is a unification hypothesis that attempts to explain the origin of the various dynamical classes of minor planets in our solar system, which operated like a giant clockwork mechanism that wound down nearly 4.5 billion years ago.

Grand tack (GT) supersedes the Nice model, where the Nice model suggested that planetary migration by Jupiter caused the late heavy bombardment (LHB), 4.1-3.8 Ga. Since the Nice model, cold classical Kuiper belt objects (KBOs) have been recognized to have formed in situ, which REQUIRES GT to reject the LHB as a statistical aberration of Apollo return samples from the Moon---LHB is at odds with GT.

My alternative REQUIRES a bimodal LHB with a narrow early pulse, which is indeed supported by Apollo return samples, Additionally, it predicts the chemistry of the LHB KBOs and REQUIRES the LHB KBOs to have been siderophile depleted and lying in the terrestrial fractionation line by their formation mechanism. Moreover, it predicts the LHB Earth impacts formed the continental tectonic plates on Earth, where continental basement gneiss formed as authigenic sedimentation with a gneissic composition, with spontaneous aqueous differentiation occurring at formation by streaming instability.

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