FOOTHILLS STRUCTURE IN NORTHERN COLORADO 737 



uplift of the monoclinal fold, as stated by Eldridge, Fenneman, etc., 

 but represent minor fracturing and slipping attendant upon, and 

 consequent to, the formation of the main monoclinal uplift and 

 its master-faults. 



Fig. 12. — Geological sketch map of southwest corner of Loveland quadrangle, 

 showing folds en echelon. For symbols, see Fig. 2. 



SUMMARY 



The master -monocline. — It has been shown by a reconstruction 

 of the original foothills fold from observed dip and strike relation- 

 ships that this represents an ideal monoclinal fold in strata origi- 

 nally continuous over the entire area of the Front Range, which 

 gradually steepens and eventually overturns as it approaches 

 Boulder and Golden. Contrary to former interpretations and 

 general belief, the maximum overturn is above the earth's surface. 



The main faults. — It has definitely been proved that the struc- 

 tural irregularities at Golden (and Boulder) cannot be explained 



