Freda Sandstone
Bear Lake Andesite
Bear Lake Andesite
An important field site is the Bear Lake Andesite, best exposed along Sevenmile Creek as shown here. This is a rare occurence where an igneous rock cuts the redbeds and could constrain the age of the rift filling redbeds which generally postdate the lavas. The Bear Lake was dated by White (1971) using K/Ar methods giving 1054 +/- 34 ma. This is a “fuzzy” date-- the error is too large to illuminate the opportunity. It may be possible to get a more precise date from resampling and analyzing, but the field sites are not simple to access and may not present suitable unaltered material for precise dating.
