Long Term Repeat Photography

Cameras have been around long enough, and there are so many good older images available, that it is now possible to return to areas that were photographed decades or even centuries ago and repeat the process. The outcome of long term repeat photography is not only visually interesting, but has been used by scientists to assess landscape level anthropomorphic change. (Perhaps most famously, at least in my line of work, by Charles Kay.) The technique is, however, only effective when things do change. Over the course of 100 years, vegetation may change, but, often, geology does not. Which makes the business of long term repeat photography difficult for those of us making pictures of rock.



The photo-graph to the left was made by E.O. Beaman in 1871. Mr. Beaman was a member of Major Powell's second expedition, and he made this picture at a place that the expedition called Bowknot Bend. At image left is a view looking downstream along the Green River; at image right is a view looking upstream along the Green River. In between is a large plateau that forces the river into a six or seven mile bend. Beaman carried the heavy photographic equipment of his era up the left side, and was picked up by the rest of his crew on the right side after they floated their three boats around the bend.



Almost exactly 140 years later, Rural Ways made this second picture, standing, without knowing it at the time, almost exactly where Mr. Beaman stood. Clearly, very little has changed, geologically speaking, since JWP and the boys were here. Two things can, however, be noted. First, on the extreme left edge of the 2011 image there is a faint scuff of sand along the far riverbank. The scuff marks the edge of a dirt road. The road is open to the public, which means that modern photographers will, almost surely, be making pictures with the roar of ATVs in their ears. This is a joy that I doubt Mr. Beaman had the pleasure of experiencing. Second, the large sandbar, visible at lower right in both images, is now covered by Tamarisk or Salt Cedar (Tamarix ramosissima). Salt Cedar is an aggressive non-native plant that was introduced to North America in the early 1800. It does not appear to be present in the Green River riparian area in 1871. Today, it has obviously covered most of the long term sandbars along the entire waterway.

In any case, I'll close this post with another quote from my favorite river narrator from 1871, Frederick Dellenbaugh: "The next morning we remained here till ten for views, and then we left Beaman on the summit of the low dividing ridge, where one could look into the river on either side and see a point which we rowed more than five miles to reach. On the right bank we stopped for dinner, and when it was about ready several of us crossed, and, helping Beaman down with his heavy boxes, ferried him to our side. The opposite bank was no more than one thousand feet in a straight line from our starting-place of the morning."