Shan, the following is a question regarding your earthquake forecasting procedure. I would be surprised if you presently have the necessary type of data to answer this question. And so it is more of a general theory question for board visitors to consider and comment on if they wish

Once again, with my present schedule it might be a while before I will be able to comment on any response notes.

If I understand it correctly, your sun shadow based forecasting procedure works by relating differences between the position of the shadow of a small object cast on a wall at a certain time of the day with the position that the shadow would have if there were no earthquakes approaching. The earthquakes cause the ground around the wall to shift slightly, thus affecting the position of the shadow on the wall.

QUESTION: How do the magnitudes of Solid Earth Tide related shadow position shifts compare with those associated with approaching earthquakes?

If it can be shown that your forecasting procedure does produce invaluable forecasting data and it is eventually used by people around the world then I believe that researchers are going to want to know the answer to that question.

THE SOLID EARTH TIDE AND "TIDAL TILT"
(Also called Horizontal Tidal Acceleration)

This background material discussion related to that question has been highly simplified in order to make it more understandable.

The Solid Earth Tide is something like an ocean tide. But it involves the twice daily up and down movement of the Earth's crust rather than the similar movement of ocean water. Its magnitude is also far less than ocean tide related vertical movement of the ocean water (differences between ocean tide crest and trough heights).

One complete Solid Earth Tide related Earth revolution very roughly represents the time that it takes the Earth to make one North - South Pole axis based revolution versus the position of the moon in the sky. This is about 25 hours. So, if the moon is directly above 0 longitude at a certain time of the day then it will once again be directly above 0 longitude about 25 hours later.

Actually I believe that one complete Solid Earth Tide revolution relates to the longitude of what I refer to as the "Gravity Point." This is the point on the Earth's surface where the combined gravitational pulls of the sun and the moon are strongest at a given point in time. However, for discussion purposes at this bulletin board, using the Sublunar Point longitude (the location which the moon is directly above) is adequate and easier to understand.

This Solid Earth Tide related movement of the crust causes the ground at any location on Earth to both tilt in different directions throughout the day versus a line drawn between that location and the center of the Earth, and twist or rotate within a plane which is parallel to the Earth's surface and perpendicular to that line.

If my understanding of the terminology is correct the amount of that tilt at a given point in time at a specific location on the Earth's surface is referred to at the "Tidal Tilt" or Horizontal Tidal Acceleration at that location.

As a result of those tilts and twists, part of the sun shadow point movement that you measure each day is associated with the Solid Earth Tide. This is partly because you use a 24 hour cycle to make your measurements. And the Solid Earth Tide works on a roughly 25 hour cycle. So Solid Earth Tide related tilts and twists at your location and hence sun shadow positions change a little each day throughout the month and throughout the year.

A computer program available at the following Web site can be used to generate Tidal Tilt data for any location on Earth. It was created by the late Hans-Georg Wenzel.

http://www.gik.uni-karlsruhe.de/~wenzel/etgtab30/