Sunday, March 1, 2015

Geo 1095: February 28, Day 789: Aquaclude Versus Aquatard

Last Tuesday, I posted a photo of a feature I described as an "intrusive aquaclude." On Twitter, I was informed that the correct word was "aquatard." It turns out, both are terms in use, but an aquatard slows groundwater flow, while an aquaclude blocks its flow entirely. As this source points out (PDF), that distinction is difficult to make in the real world. I'm pretty sure this is the same feature as that in the Tuesday post, and once again, if you enlarge the image to full size, you'll see numerous small stalactites to the right of the dike, but none to the left. However it may be farther along and another feature that's similar. I'm in the habit of posting these photos in chronological order, and this photo was taken after the three previous pictures from Paradise Lost. However, my recollection (which may not be accurate) is that Paradise Lost is a side branch, and up from, that same room- that is, we backtracked from there to the same place again.

Photo unmodified. May 9, 2013. FlashEarth Location. (Since we're underground, I have only a vague idea where this is with respect to the surface.)

No comments: