Stop #4

 

This figure shows the location of stop #4, to the south of the volcanic neck/stock.
Above Figure #6: This figure shows the location of stop #4, to the south of the volcanic neck/stock.

=====================================================================

 

Inclusions Stop #4 (33 degrees 10’ N and 117 degrees 17’ 9” W)

Here we see an inclusion of the coarse-grained Cretaceous Green Valley Tonalite enclosed within a matrix of the gray fine-grained Miocene Dacite Volcanic Plug material. The surfaces of the fine-grained volcanics are “mouse gray” where fresh and orange-brown where weathered.  What does the inclusion data tell us about the relative age of the rocks? 

 

This shows an inclusion of salt and pepper colored tonalite in a matrix of gray fine grained dacite .

 

This is a closeup of a similar picture from above.

 Above Pictures: These pictures show an inclusion of the coarse-grained tonalite enclosed within the gray fine-grained dacite.

 

Based on the field relationships and observations we have made, how would you summarize the geologic history and timing of events in the Calavera Hills area?