Please improve the consistency in the paragraph.
The surficial geology alongside Tinker Hollow in its lower and middle reaches mainly consists of alluvium. In Tinker Hollow's upper reaches, Tinker Hollow mostly consists of a till known as Wisconsinan Till.
The surficial geology alongside Tinker Hollow in its lower and middle reaches mainly consists of alluvium. However, in its upper reaches, it mostly consists of a till known as Wisconsinan Till.