The lithosphere a combination of the crust and the uppermost brittle layer of the mantle is divided into tectonic plates, including the seven major tectonic plates.
One way in which the study of populations ( human populations - I assume) affects us is that they can help predict the population size in the future and prepare us for it. For example, if we see that the population is decreasing, a country might want to consider supporting child-bearing or immigration to avoid the problem of too many people receiving pensions but not paying taxes.
Based on maps I looked on, it seems that San Antonio, Texas, is the closest.
