Another reason that I’m not a geologist

Posted on April 23, 2006 by Gene

So, I’m watching yet another documentary on the 1906 earthquake — you can’t swing a seismometer around here without hitting half a dozen commemorative documentaries, special newspaper supplements, or collector’s souvenirs — and they’re talking about trenches. Geologists dig trenches across faults and study the cross section to find past earthquakes. Over the years, layers are deposited, filling in the gaps formed by earthquakes, and one can clearly see these V-shaped fissures in the trenches.
All kinds of scientists use trenches to peer into the past, studying past civilizations that have been buried or different plant layers over time. But one thing is clear: over time, the past is buried by new layers of the present.
Which brings me to the realization that the planet is getting fatter.
You see, judging from the different layers in these trenches that I’ve seen, the planet’s surface was about 6 feet lower a few thousand years ago than it is now. So it stands to reason that in a couple thousand years, another 6 feet of sediment and dirt and junk will have been deposited on top of where we stand now.
This leads to some interesting scenarios. First off, since the earth is a sphere (more or less), this means that there is more surface area on the planet than there used to be — at least, slightly. Second, where is all this dirt and sediment coming from? Are we just digging it up from one place and then it’s being deposited somewhere else? Is the net result a wash, or is there somehow significantly more matter on the planet than there used to be, raining in from space?
In 100,000 years, when the surface of the planet is miles closer to the ionosphere, what effect will the earth’s new waistline have on it’s orbit, it’s gravitation, it’s self-esteem?