Tertiary Central Plateau and Rocky Mountains

Belt of middle Tertiary (Oligocene-Miocene) granitic to intermediate intrusive rocks & volcanics associated w/post-Laramide stage of magmatism in northern Mexico and Mid-Tertiary volcanic fields associated w/post-subduction extension in eastern Rocky Mtns
Tract ID 003pCu3009x
Country Mexico-United States of America
Commodity Cu
Study area name Mexico and US revised
Tectonic setting postconvergence
Deposit type porphyry copper
Grade-tonnage model Porphyry copper, Cu-Au subtype (Singer and others, 2008)
Geologic age
Geologic feature age Oligocene and Miocene (middle Tertiary)
Generalized age Tertiary-Paleogene
Oldest rocks age 33.9Ma
Youngest rocks age 5.33Ma
Age range 28.57Ma
Known prospects 10
Mean Cu (t/sq km) 59t/sq km
Map scales used 500K

Results of the assessment

Assessment date 2008
Estimators Francisco Cendejas-Cruz, Enrique Espinosa, Floyd Gray, Jane M. Hammarstrom, Steve Ludington, Gilpin R. Robinson, Jr., Efren Pérez-Segura, Martín Valencia-Morena, José Luis Rodríguez-Castañeda, Lukas Zürcher
Assessment depth 1km
Quantitative assessment Yes

Estimated number of deposits

Number of deposits Confidence level
1 90%
4 50%
17 10%
17 5%
17 1%
Mean estimated deposits 6.93 ±5.96 (0.86%)
Probability of mean 0.34
Probability of no copper 0.07

Estimated deposit density

(sq km)
Deposit density
per 100,000 sq km
6.93 374,330 2

Mean estimated tonnage

Copper 22,000,000
Molybdenum 130,000
Gold 1,600
Silver 7,100
Ore 4,400

Undiscovered copper resource

Confidence level 90% 50% 10% 5%
Tonnage 390,000 11,000,000 60,000,000 79,000,000

Economic analysis

Fraser country Mexico-US
Fraser type 0.68%
Fraser high 0.32%
Typical cost 1%
High cost 0%
Infrastructure setting Typical
Comments on depth 66% cover; skew deep
Expected depth distribution
0 - 250m 0.1
250m - 500m 0.3
500m - 1km 0.6
Economically recoverable resources
Copper 15,000,000t
Molybdenum 65,000t
Gold 790t
Silver 4,100t
Probability no econ recoverable 0.53
Econ NPV 4,100x $1M
Exp dollars 8.04x $1M/100,000 sq km
Exp value class Low

Bibliographic references

General Hammarstrom and others (2010)
Economic Robinson and Menzie (2012)

Deposits and prospects associated with this tract

Name Type State Country Development Details
Cerro del Gallo prospect Guanajuato Mexico Occurrence Details
Tatatila prospect Veracruz Mexico Occurrence Details
Tuligtic prospect Puebla Mexico Occurrence Details
A-O prospect Colorado United States Occurrence Details
Red Mountain prospect Colorado United States Occurrence Details
Summitville prospect Colorado United States Occurrence Details
Timberline Lake prospect Colorado United States Prospect Details
Tomichi prospect Colorado United States Prospect Details
Paradise Basin prospect Colorado United States Prospect Details