Deer Lake is an important place along the Keweenaw Fault because it illustrates that classic geometries of geologic units are not always exhibited.  In particular there is basalt exposed S of the Fault in this location, and also a variety of attitudes of bedding.  There are a number of faults suggesting fracturing of the PLV which is exposed in the map above, from DeGraff, 1976. The drawings at right represent possible stages in deformation along the fault trace that may be consistent with observed or inferred fault patterns.