Defiance Mine, Costello Mine group (Costello claims), Gleeson, Turquoise District (Courtland-Gleeson District), Dragoon Mts, Cochise Co., Arizona, USA
|Latitude & Longitude (WGS84):||31° 44' 35'' North , 109° 49' 23'' West|
|Latitude & Longitude (decimal):||31.74324,-109.82317|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
A former small underground Pb-Zn-Ag-Cu-Au-V mine located in the North-central sec. 32, T.19S., R.25E., immediately west of the Silver Bill Mine, on a southwest slope of Gleeson Ridge. Produced 1900-1958. Owned by the Giacoma Brothers.
Mineralization is a replacement deposit of oxidized ore, associated with abundant limonite, that occurred as scattered, oxidized replacement orebodies along prominent fault fissures in Pennsylvanian-Permian Naco Group limestone near the contact with intrusive quartz monzonite. Ore control was faults and fractures in limestone and also along a dike perpendicular to bedding.
In the marble, 50 to 60 feet north of its fault contact, there were found two fissures with abundant gouge, striking N.85ºE. and dipping 55º to 60ºN. Along them were replacement bodies about 5 feet wide, chiefly of limonitic material which in places contain chlorargyrite together with low percentages of lead and zinc.
Here metamorphosed impure Permian (?) limestone dipping 40º eastward is separated from marble on the north by a fault that strikes N.80ºE. and dips 55º to 60º northward. This fault is of the same general east-west system as the boundary faults within the Mystery and Silver Bill Mines. In the Defiance workings it intersects a fault that strikes northwestward and dips 60ºNE, flattening upward.
Associated rock units include the Sugarloaf Quartz Latite Porphyry, the Gleeson Quartz Monzonite and the Copper Bell Quartz Monzonite Porphyry.
Local structures include limestone near a quartz monzonite contact; brecciated fault zones, the N- to NNW-trending Gleeson Ridge Overthrust and, bedding plane faults.
Workings include an adit level with some 440 feet of drifts and 2 winzes, each 100 feet deep. Sporadic production of 10,000, or more, tons of ore occurred from the early 1900's to 1958.
25 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Tithonian - Toarcian|
145 - 182.7 Ma
|Jurassic granitic rocks|
Age: Jurassic (145 - 182.7 Ma)
Description: Granite to diorite, locally foliated and locally alkalic; includes Triassic(?) granitoids in the Trigo Mountains. This unit includes two dominant assemblages of igneous rocks. The Kitt Peak-Trigo Peaks superunit includes, from oldest to youngest: dark, foliated or gneissic diorite, medium-grained equigranular to porphyritic granodiorite, and small, irregular intrusions of light-colored, fine-grained granite. The Ko Vaya superunit, limited to south-central Arizona, includes texturally heterogeneous K-feldspar-rich granitic rocks. (150-180 Ma)
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052.