Logical_Consistency_Report:
An important consideration at the data gathering stage is the question of what the sampling unit should be. Grade and tonnage data are available to varying degrees for districts, deposits, mines, and shafts. For the deposits in this file, the following rule was used to determine which ore bodies were combined. All mineralized rock or alteration within two (2) kilometers was combined into one deposit. Thus if the alteration zones of two deposits are within two kilometers of each other, they were combined. Such an operational spatial rule is necessary for defining deposits because we must be able to classify deposits in regions with highly variable geologic information and to avoid bias in estimating undiscovered deposits in resource assessments in areas where detailed information is lacking such as under cover. The two-kilometer rule was developed to try to insure that deposits in grade and tonnage and spatial density models correspond to deposits as geologic entities. Rules such as the two-kilometer rule applied here are essential in order to have an internally consistent assessment system where the estimate of number of undiscovered deposits is consistent with the grade and tonnage model. For example, El Pachon in Argentina and Los Pelambres in Chile are here reported as one record (deposit) because of the two-kilometer rule.
Completeness_Report:
This collection includes only well explored deposits for which there is sufficient information to contribute to constructing deposit models for this type of deposit and for distinguishing subtypes. This collection excludes, therefore, known occurrences that might be of this type, but for which important information is not available. With its focus on deposits, formally defined, this compilation excludes occurrences that cannot be expected to have economic potential.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: Singer, Donald A.
Originator: Berger, Vladimir I.
Originator: Moring, Barry C.
Publication_Date: 2002
Title:
Porphyry copper deposits of the world: database, maps, and preliminary
analysis
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2002-268
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Other_Citation_Details: DOI: 10.3133/ofr02268
Online_Linkage: https://pubs.usgs.gov/of/2002/0268/
Type_of_Source_Media: Digital data
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2002
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: USGS OFR-2002-268
Source_Contribution: This is a previous major version of the present database.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Singer, Donald A.
Originator: Berger, Vladimir Iosifovich
Originator: Moring, Barry C.
Publication_Date: 2005
Title:
Porphyry copper deposits of the world: database, map, and grade and
tonnage models
Series_Information:
Series_Name: Open-File Report
Issue_Identification: 2005-1060
Publication_Information:
Publication_Place: Reston, VA
Publisher: U.S. Geological Survey
Other_Citation_Details: DOI: 10.3133/ofr20051060
Online_Linkage: https://pubs.usgs.gov/of/2005/1060/
Type_of_Source_Media: Digital data
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2005
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: USGS OFR-2005-1060
Source_Contribution: This is a previous major version of the present database.
Process_Step:
Process_Description:
This report is an update of earlier publications about porphyry copper deposits (Singer, Berger, and Moring, 2002; Singer, D.A., Berger, V.I., and Moring, B.C., 2005). The update was necessary because of new information about substantial increases in resources in some deposits and because we revised locations of some deposits so that they are consistent with images in GoogleEarth. In this report we have added new porphyry copper deposits and removed a few incorrectly classed deposits. In addition, some errors have been corrected and a number of deposits have had some information, such as grades, tonnages, locations, or ages revised. Colleagues have helped identify places where improvements were needed.
Source_Used_Citation_Abbreviation: USGS OFR-2002-268
Source_Used_Citation_Abbreviation: USGS OFR-2005-1060
Process_Date: 2008
Process_Step:
Process_Description:
Modified location given in record 260 (El Cobre, Cuba) to the inundated
pit where mining occurred in the past. Thanks to Mr. Mario J. Faz, P.G.,
of Miami Florida for finding and alerting us to this problem.
Process_Date: 20111212
