Nano confirms that this rock outcrop contains halite by its salty flavor. Credit: Meg Reitz.
The Crotone Basin accumulated sediments for nine million years before the forearc uplifted above sea level. Each layer of sand, clay, and conglomerate in the basin contains information about the environment at the time that layer was deposited.
About six million years ago, halite and gypsum were deposited in the Crotone Basin. Geologists refer to both rocks as evaporites. All bodies of water on the Earth’s surface contain dissolved ions, most commonly sodium (Na+), chloride (Cl-), magnesium (Mg2+), calcium (Ca2+), and sulfides (SO42-). When water starts to evaporate, the dissolved ions bond together and precipitate out of the solution, forming evaporites (halite = NaCl, salt; gypsum = CaMg2SO4). Most commonly we find evaporites in deserts environments that sometimes receive influxes of water, like the Great Salt Lake in Utah. Since halite and gypsum are found in the Crotone Basin, we think that water must have evaporated from the basin about six million years ago.
Dissolved gypsum formed this cave in our field area, Grotta del Palummaro. Credit: Meg Reitz.
As it turns out, evaporite deposits are found across the Mediterranean Sea during the same time period. Drill cores have turned up three kilometers of evaporites in some areas. To crystallize this much salt over such a wide area, geologists think that the entire Mediterranean Sea must have evaporated–an event called the Mediterranean Salinity Crisis (or Messinian Salinity Crisis) which lasted from 5.96 million years ago to 5.33 million years ago.
The Mediterranean Sea is located in the desert latitudes, where evaporation exceeds precipitation. The water level remains constant because water from the Atlantic Ocean enters the basin through the Straits of Gibralter.
But this wasn’t always the case. During the Messinian, a global sea level drop and local tectonics caused the land at the Straits to rise, cutting off the Mediterranean from the ocean. Since evaporation was so high, the water level dropped, concentrating the dissolved ions, and crystallizing evaporites; just like the Dead Sea in Israel, which crystallizes halite on its seafloor. Halfway through the Salinity Crisis, the four kilometers of water that filled the Mediterranean disappeared. A vast, desert basin is all that remained.
Nano and I are studying Messinian river deposits. Before and after the Salinity Crisis, rivers carried sediments from the mountains west of the basin. During the Messinian, however, something different happened.
A typical outcrop of Messinian conglomerate. Credit: Meg Reitz.
The rivers seem to have flowed from east to west, exactly opposite from today. They may also have carried chert, a rock made of silica and formed only within deep ocean basins. Chert is not found in the mountains to the west, but is found offshore below current sea level. This suggests there may have been mountains east of the Crotone Basin during the Salinity Crisis.
So, how did the mountains form and where did they go? The water in the Mediterranean Sea pushes down on and depresses the crust, much as glaciers do on land. If water is removed (as it was during the Salinity Crisis), the crust rebounds. Therefore, uplift and local tectonics may have formed mountains of deep-sea rock east of Calabria. When the the Mediterranean Sea came flooding in, the mountains would have been obliterated.
Chert (the whitish rock just above the knife) offers an important clue to what the landscape once looked like. Credit: Meg Reitz.
In order to tie these old earth events together, one must look for a reoccuring energy event. Is it the anti matter light terminating (LT) starbit we know as Proxima Centauri that NASA says is part of the Centauri A&B system that went nova 10 mya?
This seems reasonable to me in our 4.5 billion year old system. That novas come and go and affect us greatly. Was there accomplished life before? There is no way to know unless they survived to tell the tale.
So this LT starbit has an eccentric orbit that briefly touches the Oort cloud shedding anti matter. Our system every 5,000 y experiences heliospheric compressions down to Sol. All planetary bodies are heated via compressed gases. The energy field radially compresses, the planets experience increasing compression, then the Majorana transform of suspension, then the back of the energy field that is antimatter in which the planet releases the core heat via crustal fragmentation. The remains of this are what we identify as plate tectonics.
When the energy field releases compression the heliosphere returns to what we consider normal and the ferocious weather is due to the released heated gases.
As the field has since 25,000 y been decreasing in energy, first Venus, then Earth, then Mars has failed to experience the Majorana transform and the back of the energy field. The planet experiences the greatest possible compression, no Majorana transform, or expansion. The compression is held until the energy releases. The planet then experiences violent heated gas release. This has happened on Venus which watchers from Earth described as a new star. Venus has never been a comet but has been brightly visible as the heated gases lit the surface. Earth has also experience this event of maximum compression and the subsequent blowout of compressed gases.
The current compression event will not compare with past releases but compressed earth gases will release. Our lack of knowledge is due primarily to the fact that invisible, ordorless, colorless gases are not considered fatal except in long term low dose such as radon daughter products.
Our own span is about 5 my. Since about the time of the world dryness due to the initial onset of energy from the Centauri nova. I suggest we are comparable to the wolves of Chernobyl. They survive because the radiative stress is offset by their being in their own kind of Eden. We noticably have survived because compared to our beginnings, we experience less stress. This may change due to population pressures increasing stress.
A more comprehensive view would indicate that cycles of creation and destruction are the order of the day for the universe at large.