• Amanduh@lemm.ee
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    19 hours ago

    My brain isn’t working? The pole was installed and ground receded 9 meters over the years? How far into the ground was the pole driven in the beginning?

    • tal@lemmy.today
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      18 hours ago

      The pole is just an ordinary pole. In 1977, after measuring land subsidence over time, they put the signs up on it to illustrate how far the land had sunk. They could have put the signs on anything tall enough to provide enough space.

    • Cheradenine@sh.itjust.works
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      18 hours ago

      No, here’s the caption.

      Figure 2. Approximate location of maximum subsidence in the United States identified by research efforts of Dr. Joseph F. Poland (pictured). Signs on pole show approximate altitude of land surface in 1925, 1955, and 1977. The site is in the San Joaquin Valley southwest of Mendota, California.

      Link is here

      https://water.usgs.gov/ogw/pubs/fs00165/

      It uses the word ‘aquitards’ which is what my partner will undoubtedly be calling me when I go swimming