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BEFORE THE DEEPWATER OCEANS QUESTION: 65,000 km of Earth’s oceanic plates are spreading apart at an average rate of 25 km / million years. Assume there is no subduction zone and Earth’s mass has increased tenfold since the Permian extinction. How big would Earth be if Earth started out the size of Mars, 250 million years ago. Chat GBT REPLY: Using the assumed values—a global mid-ocean ridge length of about 65,000 km and an average spreading rate of roughly 25 km per million years—it is possible to estimate how much new surface area could be created over the 250 million years since the Permian–Triassic extinction event. Over that interval, the plates on opposite sides of a ridge would separate by about 6,250 km. Multiplying this widening distance by the total ridge length gives a newly generated crustal area on the order of 4 × 10? km². If one assumes that none of this crust is destroyed by subduction and that all of it simply adds to the planet’s surface, this amount of new area is comparable to the present area of Earth’s oceans. If the starting planet had the surface area of Mars—about 44 million km²—and this additional oceanic area were added through continuous spreading, the total planetary surface would grow to roughly 550 million km². Converting that surface area back into the radius of a sphere yields a radius of roughly 6,600 km, which is quite close to the modern radius of Earth, about 6,371 km. In purely geometric terms, therefore, the amount of crust that could be generated by spreading at the assumed rates over 250 million years is of the same order as the surface area required for a planet to grow from roughly Mars-sized to approximately the present dimensions of Earth. This comparison does not by itself establish that such expansion occurred; rather, it shows that the scale of crustal production implied by those spreading rates is large enough, in principle, to account for an ocean-sized increase in surface area over that time span if no crust were recycled. In conventional plate-tectonic interpretations, however, most oceanic crust created at mid-ocean ridges is eventually destroyed at subduction zones, which keeps the total surface area of the planet approximately constant. Nonetheless, the calculation illustrates that the magnitude of seafloor spreading over hundreds of millions of years is substantial enough to produce an area comparable to the modern ocean basins.
A map of the titanium abundances on the Moon’s surface indicates extremely high concentrations compared to terrestrial rocks. We mimicked the high-Titanium basalts using high-temperature experiments clearly demonstrating how the melt-solid reaction is integral in understanding the formation of these unique magmas. Titanium deposits only on the near side of the moon suggest the near side surface may have been heated by atmospheric friction before an impact with Earth knocked Earth out of geo-synchronous orbit with Mars, and the planets into orbits closer to and farther from the sun. Evidence the impact knocked Earth into a closer solar orbit is before the extinction Earth’s climate was temperate with boreal forests, ice caps and lengthy ice ages. After the extinction the climate was tropical without ice caps or ice ages.
The impact causing the extinction shattered the lithosphere into plates and created a depression which became the seabed of the Pacific Ocean. The Pacific Ocean plates have been spreading for 250 million years and the Atlantic plates have been spreading for 65 million years which has increased planetary surface area two and a half times since the beginning of the Mesozoic. Atlantic Ocean
The tenfold increase in planetary mass has increased surface gravity 2.5 times since the beginning of the Mesozoic era , allowing terrestrial plants and animals to grow to prodigious sizes in reduced gravity. In humans and bovids, cortical bone has been evaluated to withstand maximum stress. Hence, within the context of comparable loading regimes, the mechanical state of each sauropod model examined suggests that all skeletal pedal postures would most likely have resulted in mechanical failure (e.g., stress fractures).
This state would have been intensified when subjected to repetitive heavy loadings, as would be expected during normal locomotion, ultimately resulting in fatigue fracture in all digits. Being unable to support or move properly, the high probability of mechanical failure would have had a substantial impact on the animal’s survival.
The huge Quetzalcoatlus northropi lived 70 million years ago, stood as tall as a giraffe on the ground, more than five meters tall and weighed 250 kilograms. The Kori bustard is the heaviest living animal that can fly. Males weigh between 10 and 16 kilograms and the biggest up to 23 kg. For comparison, the wandering albatross has a larger wingspan, but only the biggest reach even 16 kg.
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Atoms are Electrons and Positrons
