Geology of the Christmas Quadrangle Gila and Final Counties Arizona
GEOLOGICAL SURVEY BULLETIN 1161-E
Geology of the Christmas Quadrangle Gila and Final Counties Arizona
By RONALD WILLDEN
CONTRIBUTIONS TO GENERAL GEOLOGY
GEOLOGICAL SURVEY BULLETIN 1161-E
A description of the rocks and structural features of an area containing some major copper deposits of southeastern Arizona
UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1964 UNITED STATES DEPARTMENT OF THE INTERIOR
STEWART L. UDALL, Secretary
GEOLOGICAL SURVEY
Thomas B. Nolan, Director
For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 CONTENTS
Page Abstract-______-__-______-___-_-___-_-___._ El Introduction ______2 Location and accessibility______3 Physical features ______4 Climate.______5 Previous work______6 Acknowledgments. ______8 Regional geologic setting.______8 Precambrian rocks______9 Older(?) Precambrian rocks___-______-_--_------_-_ 9 Schist______.______-_ 10 Metavolcanic rocks______-______-_-__-_-_---. 10 Granite ______11 Granodiorite._ ___-___-______-______--__--_---_---- 12 Apache Group.______12 Pioneer Formation______-___-----_---_ 13 Scanlan Conglomerate Bed______-_-__------_--_- 13 Dripping Spring Quartzite____----_---_---__---__------14 Barnes Conglomerate Member______-___----_---_----- 15 Upper members of Dripping Spring Quartzite______---_ 15 Mescal Formation______-______-_-___-__----- 16 Basalt.______----___---- 17 Troy Quartzjte___-______17 Diabase and diorite______.______-______----_-__--- 19 Cambrian rocks, undivided______20 Devonian rocks.______22 Martin Formation.______22 Mississippian rocks.______23 Escabrosa Limestone______-______-__--_-----_ 23 Pennsylvanian rocks.______24 Naco Limestone...______24 Cretaceous rocks______25 Unnamed sedimentary rocks______.______25 Unnamed volcanic and sedimentary rocks.______-_--.- 26 Cretaceous(?) or Tertiary rocks______.______--_-_---_ 27 Microdiorite.______28 Feldspar-mica porphyry_-______-_-_----_-_---- 28 Hornblende andesite_____-__-______--__--___-_-_-_----- 30 Tertiary rocks______-.-__-_ 32 Conglomerate._---______-__--__--_--- 32 Older volcanics______-_--__-_-----_- 32 Intrusive rhyolite______- 34 Gravel. ______34 Basalt and andesite___-______.___.______-----_-_-----_ 35 Tuff and rhyolite______35 in 17 CONTENTS