I’m so confused!!!
This was a bizzarre scene. The herbacious material growing along the edge of the water was trembling in the most unusual manner – like it was being agitated by something beneath the water and yet there was nothing there – the whole bed was vibrating and it was not possible to see why – was it atmospheric or something to do with the current – I have no idea.
Anyway the point of this picture is to illustrate the clay deposits in the area of the sinking stream. Clay is a very fine-grained mineral that results from the breakdown of silicate bearing rocks. The usual means of corrosion is carbonic acid.
In this picture it is possible to see ridged striations in the stream bank – varves. In the winter fine sediments are deposited at the bottom of a still body of water the clay layer builds up. (Hard to see by this picture but the clay is pink) In the summer coarser sediment is deposited. The silt layers are more quickly eroded by the stream hence the striations.
This clay layer lying up against the limestone ridge beneath suggested some kind of glacial intervention to Marcus and Daryl. If I recall correctly somebody had mentioned the possibility of the systems in the area forming in reverse – that is the water pushing up from the stream’s present point of resurgence. Come to think of it – that may explain the difuse way in which the water leaves the system downstream. Sorry, just thinking while I am typing.
Anybody who knows the geography of this area care to throw in an interpretation?