Steps Towards Predicting Earthquakes

Just realized something that made me rewrite everything i wrote recently about earthquakes.

Earth's higher crust temperature varies. Which means, exactly like in the case of bridges, railroads and freeways, it may be dilating or contracting. Imagine what happens when the crust expands. Will probably raise up, reducing the pressure underneath. Here is everything i knew before that:

Tectonic plates theory says the Earth is made of a mosaic of plates, big and small, of which number varies according to different authors, all rigid or each made of one piece, and earthquakes occur at the areas where they meet and... rub against each other, being pushed underneath by concurrent or divergent horizontal convection currents.

The phase changing theory says bubbles of magma are slowly raising to the surface in areas where there are descending or ascending convection currents again pushing vast areas of semi-loose rocks floating on magma (continents, ocean bottoms) against each other or apart from each other. Some of the bubbles may erupt  at the surface as volcanos, but some may freeze before that.

However, magma is a complex mixture and has several freezing points. Put scientifically, it has a complex phase diagram (of lower mantle), with several different solid phases, each with its own volume.

When magma in a bubble (which may have the size measured in miles) changes phase progressively with high speed, starting with one point, it expands or contracts suddenly but progressively until the whole bubble has changed phase. The phase change is ultimately triggered by a small but sudden change in pressure.

The surface earthquakes occur when water from the aquifer trapped in deep caves at near boiling point at that temperature and pressure according to the depth and other factors, boils suddenly, again triggered by a change in pressure, thus changing phase from liquid to vapor.

One can argue that atmospheric pressure is very small compared to the pressure in those bubbles. It may be, but the pressure is distributed over a large area and if the bubble is at that tipping point, it can make a difference. So it is a factor.

Other obvious factor may be the weight of precipitations, which may be enormous on the whole seismic area, or the lack of it.

Position of Earth in the Sun Earth Moon triangle. Gravity forces between these celestial bodies is enormous. The Moon pull is in the range of 10 to the power of 15 ton-force.

Thing is, it is not the same on the whole Earth, but greater on the side of the Earth where Moon is closer, because gravitational force varies with the square of distance, one Earth diameter being about 1/6 to 1/7 of the distance between Earth and Moon.

We have much greater forces between Earth and Sun, but those do not vary as much because the distance difference between those of the opposite side of the Earth is much smaller than distance to Sun.

As a result, Earth is being deformed by the combined actions of the two which is translated in lesser known ground tides, which can be in the order of 1-2 meters and more visible ocean and smaller seas tides.

Pressure inside the crust due to gravity forces described above changes daily with Earth's rotation and exposure towards Sun and Moon and also with seasons, due to the tilt of Earth's axis. After billions and millions of years, Earth has stabilized which means those variations alone do not cause earthquakes anymore.

Or pressure and/or maybe speed of pressure changes due to gravity is outside the range for producing an earthquake.

The immediately accessible measure of combined Sun-Moon variations of gravity pull on Earth's surface is given by tides.

We now have pretty accurate predictions for atmospheric pressure, temperature and precipitations, also for tides in or near major seismic areas. Just by looking at those, one can get an idea when an earthquake may occur. Temperature (of the crust) rising, recent cease of precipitations, barometric pressure drop, high tides.

For this reason, i recently put on the right side of my blog links (last in list) to those charts for the seismic area of Vrancea, Romania. Until someone using those or more advanced mathematical models than using tides as measure for gravity influences, can make a chart just for earthquakes probabilities in known seismic areas.

Though one cannot make an accurate prediction for an earthquake using the linked charts, one can easily figure the time when it cannot happen (rule out).