This is the first of several posts, reporting the roadside geology of western New York and central Vermont. Today, we will visit Binghamton, New York. This small city (urban population less than 50 thousand) sits at the confluence of two perennial, gravel-bedded rivers (Fig. 1).
Enough of Holocene and Anthropocene geology. The fascinating thing about this region is that it preserves a huge volume of sediment eroded from mountains that were growing during the Devonian Period, about 350 million-years ago (Fig. 4).
We didn’t have the time or resources to go on a quest for rocks that would reveal what was happening during the Devonian Period, so we took some photos of charismatic blocks that had been removed from their original location and “deposited” along the path that followed the Chenango River through downtown Binghamton (Figs. 5 and 6).
The title of this post refers to the outer limits of a broad plain that was receiving gravel, sand, silt, and mud from a rapidly rising mountain belt–probably like western North America today (e.g. the Sierra Nevada mountains). It wasn’t a continental collision, but it was pretty massive, with elongate swaths of sediment subsequently buried by what came later.