Peru-Ecuador Cretaceous Almacen

Cretaceous plutons, mostly calc-alkaline diorites and tonalites, principally of the Coastal batholith and smaller batholiths.
Tract ID 005pCu1007
Country Ecuador-Peru
Commodity Cu
Study area name Andes
Tectonic setting continental margin
Deposit type porphyry copper
Grade-tonnage model General porphyry copper model (Singer and others, 2005)
Geologic age
Geologic feature age Cretaceous
Generalized age Mesozoic
Oldest rocks age 145.5Ma
Youngest rocks age 65.5Ma
Age range 80Ma
Identified Cu resources 600,000metric tons
Known prospects 8
Mean Cu (t/sq km) 130t/sq km
Map scales used 1M

Results of the assessment

Assessment date 2005
Estimators Carlos Mario Celada, Vladimir I. Berger, Charles G. Cunningham, Alejandro Diaz, Mariano Gajardo M., Carlos Portigliati, Alvaro Puig Godoy, Donald A. Singer, David M. Sutphin, Waldo Vivallo S., and Eduardo O. Zappettini
Assessment depth 1km
Quantitative assessment Yes

Estimated number of deposits

Number of deposits Confidence level
1 90%
3 50%
8 10%
8 5%
8 1%
Mean estimated deposits 3.83 ±2.64 (0.69%)
Probability of mean 0.3
Probability of no copper 0.07

Estimated deposit density

(sq km)
Deposit density
per 100,000 sq km
2 5.83 107,300 5

Mean estimated tonnage

Copper 14,000,000
Molybdenum 340,000
Gold 320
Silver 4,200
Ore 2,700,000,000

Undiscovered copper resource

Confidence level 90% 50% 10% 5%
Tonnage 310,000 6,800,000 33,000,000 51,000,000

Economic analysis

Fraser country Peru* and Ecuador (mostly in Peru)
Fraser type 0.44%
Fraser high 0.56%
Typical cost 0.27%
High cost 0.73%
Infrastructure setting Mixed
Comments on depth deeply eroded in parts of tract, S end less so; skew shallow
Expected depth distribution
0 - 250m 0.35
250m - 500m 0.25
500m - 1km 0.4
Economically recoverable resources
Copper 7,700,000t
Molybdenum 140,000t
Gold 130t
Silver 2,200t
Probability no econ recoverable 0.44
Econ NPV 1,700x $1M
Exp dollars 11.31x $1M/100,000 sq km
Exp value class Low

Bibliographic references

General Cunningham and others (2008)
Economic Robinson and Menzie (2012)

Deposits and prospects associated with this tract

Name Type State Country Development Details
Alondra prospect Arequipa Peru Prospect Details
Anita de Tibilos prospect Ica Peru Occurrence Details
Chavez N2 prospect Ica Peru Unknown Details
Eliana prospect Ica Peru Unknown Details
Los Linderos prospect Loja Ecuador Occurrence Details
Los Pinos deposit Lima Peru Prospect Details
Puquio prospect Ica Peru Occurrence Details
Rio Playas prospect Loja Ecuador Occurrence Details
Tingo prospect Huancavelica Peru Prospect Details
Almacen prospect Ica Peru Past Producer Details