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Sep24-11, 05:58 PM
P: 546
Quote Quote by Edwin View Post
I hope this is not overly speculative: I was wondering if seasonal temperature variations over large land masses can cause the ground to expand in such a way as to offset the straight line distance between two landmarks 730 kilometers apart by about 10 meters, or so? I had spoken a while back with a person who was familiar with bridge design, who explained that bridges can expand during summer due to the materials in the bridges being heated to higher temperatures during the summer months. So a natural question in my mind was whether the same thing is true for general land masses. I have tried searching around, but have not found any information that states that the ground of land masses in various regions expands during summer months in a way as to significantly change distances between landmarks (but I did not look very hard: it was a quick search, about 5 minutes of googling various links, so if there is an obvious link, I apologize).

I was wondering if the distance between the two facilities could have deviated by a factor of plus or minus 10 meters as a result of the expansions and contractions of the land mass the facilities and tunnels sit on due to seasonal variations in temperature of the ground?

p.s. I have removed this post a couple of times, as I think I am having problems with posting successfully. I am not sure if I did this right, but if this post ends up in more than one place, I apologize, and to the moderator, please delete any duplicates. Any duplicates is unintentional and is a result of my having difficulty with posting: I am not sure if I am having problems with my account, or if it is just plain error on my side.
Were that the case, there would have been seasonal variations in the inferred speed, which there were not. Additionally, they've included data tracking the change in distance over time; and, it only comes to centimeters, even with the effects of an earthquake.