Our magnetic field protects the earth from dangerous cosmic rays. Without it there would not be life here:

https://phys.org/news/2019-05-earth-core-common-salad.html

"A Yale-led team of scientists may have found a new factor to help explain the ebb and flow of Earth's magnetic field—and it's something familiar to anyone who has made a vinaigrette for their salad.

"Earth's magnetic field, produced near the center of the planet, has long acted as a buffer from the harmful radiation of solar winds emanating from the Sun. Without that protection, life on Earth would not have had the opportunity to flourish. Yet our knowledge of Earth's magnetic field and its evolution is incomplete.

"In a new study published May 6 in the Proceedings of the National Academy of Sciences, Yale associate professor Kanani K.M. Lee and her team found that molten iron alloys containing silicon and oxygen form two distinct liquids under conditions similar to those in the Earth's core. It is a process called immiscibility.

"'We observe liquid immiscibility often in everyday life, like when oil and vinegar separate in salad dressing. It is surprising that liquid phase separation can occur when atoms are being forced very close together under the immense pressures of Earth's core," said Yale graduate student Sarah Arveson, the study's lead author.

"Immiscibility in complex molten alloys is common at atmospheric pressure and has been well documented by metallurgists and materials scientists. But studies of immiscible alloys at higher pressures have been limited to pressures found in Earth's upper mantle, located between Earth's crust and its core.

"Even deeper, 2,900 kilometers beneath the surface, is the outer core—a more than 2,000-kilometer thick layer of molten iron. It is the source of the planet's magnetic field. Although this hot liquid roils vigorously as it convects, making the outer core mostly well-mixed, it has a distinct liquid layer at the top. Seismic waves moving through the outer core travel slower in this top layer than they do in the rest of the outer core.

***

"Using laser-heated, diamond-anvil cell experiments to generate high pressures, combined with computer simulations, the Yale-led team reproduced conditions found in the outer core. They demonstrated two distinct, molten liquid layers: an oxygen-poor, iron-silicon liquid and an iron-silicon-oxygen liquid. Because the iron-silicon-oxygen layer is less dense, it rises to the top, forming an oxygen-rich layer of liquid.

"'Our study presents the first observation of immiscible molten metal alloys at such extreme conditions, hinting that immiscibility in metallic melts may be prevalent at high pressures," said Lee.

"The researchers said the findings add a new variable for understanding conditions of the early Earth, as well as how scientists interpret changes in Earth's magnetic field throughout history."

Comment: The evidence keeps piling up as to how special the Earth has to be to support life. It has to be by design.

Plate tectonics are required for complex life to exist. Our crustal movement is very old, estimated now at 2.5 byo.

https://cosmosmagazine.com/earth-sciences/the-earth-began-to-move-2-5-billion-years-ago...

"Tectonics – the movement of large surface plates across the globe – is the geological driver responsible for continental drift, the creation of mountain ranges, earthquakes, and the constant slow recycling of minerals into, and out of, the planet’s crust.

"Exactly when the phenomenon began in the 4.5 billion-year history of the Earth is a matter of considerable debate. One school of thought contends that it has been a feature of the planet’s geology almost since its formation, while another suggests that it emerged only comparatively recently, about one billion years ago.

***

"Quartzite, marble and anthracite are all examples of metamorphic rocks. By examining them it is possible to accurately measure the heat and pressure to which they were subjected, and the time period over which this occurred.

"With a large enough sample across a wide enough distribution, therefore, it is possible to estimate heat flow patterns through the ancient Earth – and heat flow is very strongly associated with plate movements.

"Holder and colleagues therefore gathered samples from 564 sites around the world. The oldest dated to about three billion years ago, but metamorphic creation kicked up in frequency about half a billion years later – indicating, the researchers conclude, the start of tectonics.
The findings – if confirmed by further analysis – are likely to force a rethink about the early history of the Earth.

“'The framework for much of our understanding of the world and its geological processes relies on plate tectonics,” says Holder.

“'Knowing when plate tectonics began and how it changed impacts that framework.'”

Comment: This fits my concept of God in control and planning ahead by preparing the Earth for the more complex life that was yet to come

A new theory estimating early days short length and how that may have related to staggered oxygen production from cyanobacteria mats:

https://www.sciencemag.org/news/2021/08/totally-new-idea-suggests-longer-days-early-ear...

"Now a research team has proposed a novel link between how fast our planet spun on its axis, which defines the length of a day, and the ancient production of additional oxygen. Their modeling of Earth’s early days, which incorporates evidence from microbial mats coating the bottom of a shallow, sunlit sinkhole in Lake Huron, produced a surprising conclusion: as Earth’s spin slowed, the resulting longer days could have triggered more photosynthesis from similar mats, allowing oxygen to build up in ancient seas and diffuse up into the atmosphere.

***

"Microbes that became cyanobacteria evolved the molecular machinery for photosynthesis early on, letting them convert carbon dioxide and water into sugars and oxygen. Researchers have long thought these microbes provided Earth’s initial supply of oxygen, over the eons creating an environment that favored the evolution of aerobic life in all its forms. But they always puzzled over why about a billion years passed between the first photosynthetic microbes, which fossils indicate arose about 3.5 billion years ago, and the first good geological evidence for a buildup of oxygen.

***

"Many agree that 4.5 billion years ago, a day was only about 6 hours long. By about 2.4 billion years ago, the models predict, the pull of the Moon had slowed that spin to about a 21-hour day. Earth’s rotational speed then stayed constant for about a billion years, as its gravitational pull countered the Moon’s drag. Those forces fell out of balance about 700 million years ago, because the resonance cycle between Earth and the Moon is not completely stable, and the planet’s spin slowed to its current speed, creating a 24-hour day, according to the models.

***

"...oxygen first jumped during what’s called the Great Oxygenation Event, some 2.4 billion years ago, and then again during the Neoproterozoic era, more than a billion years later. During the Paleozoic, about 400 million years ago, there was a final major increase in atmospheric oxygen.

***

"Models suggest the amount of oxygen on Earth increased in a stepwise fashion, starting with the Great Oxygenation Event (GOE) about 2.4 billion years ago, followed by a plateau for a "boring billion" years. Oxygen rose again in the Neoproterozoic Oxygenation Event (NOE) and Palaeozoic Oxidation Event (POE). Day length rose in the same stepped pattern, suggesting that the added light boosted photosynthetic microbes, fueling increases in oxygen.

"This “elegant” idea helps explain why oxygen didn’t build up in the atmosphere as soon as cyanobacteria appeared on the scene 3.5 billion years ago, says Timothy Lyons, a biogeochemist at the University of California, Riverside. Because day length was still so short back then, oxygen in the mats never had a chance to build up enough to diffuse out. “Long daytimes simply allow more oxygen to escape to the overlying waters and eventually the atmosphere,” Lyons says.

"Still, Lyons and others say, many factors likely contributed to the rise in oxygen. For example, Fischer suspects free-floating cyanobacteria, not just those in rock-affixed mats, were big players. Benjamin Mills, an Earth system modeler at the University of Leeds, thinks the release of oxygen-binding minerals by ancient volcanoes likely countered the early buildup of the gas at times and should be factored into oxygen calculations."

Comment: The Earth evolved to its present state over time. The universe evolved to its present state after the BB. Life evolved from simple Archaea. Our reality has appeared to reach its present state by processes of evolution. If God is in charge He uses evolution to reach His goals.

Supply oxygen at deep depths:

https://phys.org/news/2022-08-giant-deep-ocean-life.html

"A previously overlooked factor—the position of continents—helps fill Earth's oceans with life-supporting oxygen. Continental movement could ultimately have the opposite effect, killing most deep ocean creatures.

***

"The water at the ocean's surface becomes colder and denser as it approaches the north or south pole, then sinks. As the water sinks, it transports oxygen pulled from Earth's atmosphere down to the ocean floor.

"Eventually, a return flow brings nutrients released from sunken organic matter back to the ocean's surface, where it fuels the growth of plankton. Both the uninterrupted supply of oxygen to lower depths and organic matter produced at the surface support an incredible diversity of fish and other animals in today's ocean.

"New findings led by researchers based at UC Riverside have found this circulation of oxygen and nutrients can end quite suddenly. Using complex computer models, the researchers investigated whether the locations of continental plates affect how the ocean moves oxygen around. To their surprise, it does.

***

"'Many millions of years ago, not so long after animal life in the ocean got started, the entire global ocean circulation seemed to periodically shut down," said Ridgwell. "We were not expecting to find that the movement of continents could cause surface waters and oxygen to stop sinking, and possibly dramatically affecting the way life evolved on Earth."

"Until now, models used to study the evolution of marine oxygen over the last 540 million years were relatively simple and did not account for ocean circulation. In these models, ocean anoxia—times when oceanic oxygen disappeared—implied a drop in atmospheric oxygen concentrations.

***

"This study used, for the first time, a model in which the ocean was represented in three dimensions, and in which ocean currents were accounted for. Results show that collapse in global water circulation lead to a stark separation between oxygen levels in the upper and lower depths.

"That separation meant the entire seafloor, except for shallow places close to the coast, entirely lost oxygen for many tens of millions of years, until about 440 million years ago at the start of the Silurian period.

"Circulation collapse would have been a death sentence for anything that could not swim closer to the surface and the life-giving oxygen still present in the atmosphere," Ridgwell said. Creatures of the deep include bizarre-looking fish, giant worms and crustaceans, squid, sponges and more.

"The paper does not address if or when Earth might expect a similar event in the future, and it is difficult to identify when a collapse might occur, or what triggers it. However, existing climate models confirm that increasing global warming will weaken ocean circulation, and some models predict an eventual collapse of the branch of circulation that starts in the North Atlantic.

***

"'You'd think the surface of the ocean, the bit you might surf or sail on, is where all the action is. But underneath, the ocean is tirelessly working away, providing vital oxygen to animals in the dark depths," Ridgwell said.

"'The ocean allows life to flourish, but it can take that life away again. Nothing rules that out as continental plates continue to move."

Comment: another way plate tectonics support life

They always tell us a lot:

https://www.sciencemagazinedigital.org/sciencemagazine/library/item/03_may_2024/4192470...

"Tiny grains of a mineral called zircon might have witnessed the fall of rain on Earth’s earliest dry land some 4 billion years ago, when oceans likely covered most of the planet. The chemical composition of the crystals, plucked from rocks in Australia, hint that they formed from magmas doped with freshwater, a team of scientists argues. That would only have been possible on terra firma, they say.

“'We found evidence for two things: There was land above sea level and, at the same, that this land interacted with freshwater,” says Hamed Gamaleldien, a geochemist at Khalifa University who presented the results last month at a conference of the European Geosciences Union. “This means you start to have the hydrological cycle, and you started to have the recipe for the start of life.”

***

"The zircons represent a rare report from the mysterious Hadean, the geological time period that ended about 4 billion years ago, 500 million years after Earth’s formation. The planet, originally a ball of magma, had cooled off and formed a crust. Somehow, perhaps from a bombardment of water-rich asteroids, it had accumulated a global ocean. Earth may have remained watery for quite some time— at least until tectonic processes began to recycle Earth’s crust into its interior, and magma bubbled up in chains of island volcanoes that eventually fused into continents.

"Much of this is guesswork, because almost no rock survives from the Hadean. The oldest rock with a reliable age—a gneiss from Canada—is 4.03 billion years old. The only surviving material from before then are zircons, found embedded in younger rock, which are as much as 4.4 billion years old. “Just about any information that we can get from these Hadean zircons is useful because it’s our singular record of the Earth’s first 500 million years,” says geologist Stephen Mojzsis of the HUN-REN Research Centre for Astronomy and Earth Sciences.

"Zircons are tough little minerals, often outliving the original rock they formed within. For example, Hadean zircons found in Australia’s Jack Hills sit in rock that’s about 3 billion years old—having eroded out of even older rocks that have long since disappeared. Zircons contain small amounts of elements such as uranium that allow them to be precisely dated, as well as other clues about ancient Earth. Researchers have used zircons to try to date the onset of plate tectonics and the origin of continental crust. They even offer hints of the origin of life: In 2015, Bell and her colleagues found bits of graphite in a 4.1-billion-year-old zircon that might have been derived from biological carbon.

***

"Before Gamaleldien and his colleagues could make the measurements, they had to collect, polish, and individually inspect thousands of zircons from two rock chunks pulled from the Jack Hills. They analyzed about 1400 zircons that were between 1.85 billion and 4.28 billion years old.

***

"To be certain, the researchers performed tens of thousands of computer simulations of zircons forming from magmas mixed with seawater, rainwater, or some combination of both. Only with at least some freshwater could the team reproduce the exceptionally light isotopic signature of their zircons.

***

"If Gamaleldien and his colleagues are right, however, the late Hadean might have been habitable long before the appearance of the first fossils. Not all hypotheses for the origins of life require dry land. But some invoke freshwater hot spring environments. Gamaleldien hopes his discovery will spark renewed interest in a search for life before 4 billion years. “Whether there’s life or not, we don’t know,” he says. “But you had the recipe.'”

Comment: fossilized stromatolites from 3.8 byo support the zircon theory. What is apparent is the Earth was barely formed before life tried to appear. The whole story looks like a designed process following the purpose of creating life, ending with humans. Looked at as a series of necessary contingencies, think of what the odds are if it is all by natural chance. Impossibly an enormous set of odds.

A new study:

https://www.sciencenews.org/article/weaker-magnetic-field-marine-life-big

"Earth’s magnetic field protects life from harmful cosmic radiation. But sometime between about 590 million and 565 million years ago, that security blanket seems to have been much thinner — with far-reaching effects for the development of life on Earth, researchers suggest.

"A weaker magnetic field could account for the higher levels of oxygen recorded in the Earth’s atmosphere and oceans around that time — and for the ensuing proliferation of macroscopic marine animals, the team reports in the May 2 Communications Earth & Environment.

***

"Now, the same team has examined rocks from Brazil dating to about 590 million years ago. Earth’s magnetic field was even weaker back then, the researchers found — just one-thirtieth the modern-day value. That’s the lowest magnetic field strength ever measured for our planet, Tarduno says. “The field almost completely collapsed.”

"If Earth’s magnetic field remained low during the roughly 25-million-year interval bracketed by those samples — and less-precise data from other teams suggest that it did — that’s a remarkable coincidence, Tarduno says. Earth’s magnetic field was dramatically weaker right around the time of the Ediacaran Period, when oxygen levels increased in both the atmosphere and oceans; rock records show higher-than-normal levels of oxygen around that time. It’s also a period when macroscopic animals began to proliferate in the world’s oceans.

"Perhaps there’s a link there, Tarduno and his colleagues propose in the new paper. A weaker magnetic field would have meant less protection from energetic cosmic particles. “Our shield was down,” Tarduno says. Those particles would have broken apart water molecules in the early Earth’s atmosphere. Hydrogen, being extremely light, would have readily escaped into space, while oxygen would have remained behind. Over time, that imbalance would have tipped the scales in favor of a more oxygen-rich atmosphere and oxygen-enriched oceans, the researchers suggest.

"The larger, more mobile animals that the fossil record shows developed during the Ediacaran Period would have needed all that oxygen, Tarduno and his collaborators suggest. It’s no secret that bigger animals require more oxygen than their microscopic brethren, Tarduno says. “This oxygenation set the stage for large life.'”

Comment: It seems our magnetic field plays a dynamic role in its pervasive influence on life at all times.