https://postimg.cc/gallery/Cf95fLt/ed6c639e
First take with a grain of salt, I am an idiot relative to real scientist like Einstein.
This is a mental simulation and hypothesis. Thoughts are NOT proven with facts. Ideas are only worth whatever one's interest is, and 0 if proven false.
Was there a Cataclysmic tidal wave flooding the earth?
If a large meteor, or comet, hit the earth in the ocean, then ripples of waves could circle the earth. This may happen more than once.
Picture a small globe with 100% ocean surface of a sufficient depth throughout. Now create a ripple at one spot. It would extend outwards and converge on the point on the globe opposite to the original impact point, and continue to converge and diverge back and forth between these two points. It would do so alternatively between the two opposing points until the energy dissipates.
Now for a planet like earth with irregular land mass, the second convergent point would not be a point but a region, and the convergence time would not be uniform. The third convergence point would be more distorted and so on.
Such tidal waves could erode sedimentary layers on land and under shallow sea, and later deposit that eroded silt when the velocity of the wave gets low.
Scrap Markings, Perhaps? on the Earth
00-Africa-W-Sahara
01-Africa-W-Sahara
02-Africa-W-Sahara
06-Africa-S-South Africa-Kgalagadi Transfrontier Park 1
11-Asia
12-Australia zoom
13-Australia
14-South America
15-North America 1
16-North America 2
27-South America-W-Peru
Note It could be wind erosion but what if it is not. What if it was caused by boulders being dragged by a tidal wave.
Look at these scrap markings. I am thinking of boulders being dragged in a tidal wave and eroding the surface.
Maybe a comet hit in the ocean causing a wave that could circle the earth more than once.
Desert/Semi-Arid Regions
03-Africa-S-Namibia
04-Africa-S-Namibia
05-Africa-S-Namibia-Salt Pan
07-Africa-S-South Africa-Kgalagadi Transfrontier Park 2
08-Africa-S-South Africa-Kgalagadi Transfrontier Park 3
09-Africa
The Sahara Desert
17-Mexico-NW-near Cali
18-Utah-Glen Canyon
19-Utah-Glen Canyon
21-Australia-Munga Thirri 1
22-Australia-Munga Thirri 2
23-Australia-Munga Thirri 3
24-Australia-Simpson Desert
25-South America-W-Bolivia 1
26-South America-W-Bolivia 2
Note: Generally the western region is more arid of land masses around the equator. Explanation below.
Namibia to the west of the southern part of Africa has a desert region. It looks like wind erosion had formed giant sand dunes. The wind could be very strong there. Maybe just as how the wind forms waves on the sea by resonance, it forms waves on the land in the form of sand dunes in the predominant wind direction. That is my bet.
Check this out:
https://www.windy.com/?15.475,-3.977,5
The wind direction is a bit misleading because you have to look at the wind at different altitudes, and at different times of days to get the ground predominant wind direction.
Generally, arid regions will persists where the land surface can be hot and not allow condensation, for the day time. In the night, dew may form IF the humidity was high.
Generally, red mineral sand will get hotter than white sand because of broader band absorption.
Generally, there is rise of air in the day, and exposed water is loss to provide humidity for the rising air current.
Generally, also, there is a westward movement of air. In the day, at the solstice point X, there is an upward movement of air. Slightly north of X, at higher altitudes, there is a northward movement of air.
Generally, land regions nearer the west of the land mass get less rain.
Sometimes mountains filter the humidity from the atmosphere to the east side of the mountain and little remains on the west side.
In the night, dew on the land to the east near the sea.
Just the change in time of day can cause clouds to form if enough humidity was present.
The west region of land masses at the equator may not be an end point in the water cycle.
What if we could carefully make it end in the water cycle.
If there was a cataclysm, the new presence of red sand and the loss of vegetation could mess with the existing water cycles.
Note: The salt pan in Namibia is a suggestion that sea water did come onto the land. Even if by wind, but if that much water was coming from the sea, then I would expect the land to be less dry. I wonder if it was done in a short period like during a tidal cataclysm.
Note: Some areas to me look like scarp land and others sand dunes.
Munga Thirri in East Central Australia is near the scraped lad with the red deposit as well as Simpson Desert. West of that is also arid. There is Gibson Desert Nature Reserve and Great Victoria Desert Nature Reserve in Australia.
West of South America in part of Bolivia, the land is Semi-arid, but not so arid as the mountains nearby can filter some of the humidity via cooling.