MAGMATISM AND HYDROTHERMAL SYSTEM OF THE KINGKING PORPHYRY COPPER DEPOSIT:

AN INSIGHT INTO THE MINERALIZATION OF THE COPPER-GOLD BELT IN SOUTHEASTERN

MINDANAO, PHILIPPINES

LEILANIE O. SUERTE, D. Eng.

Mines and Geosciences Bureau Regional Office No. 6

Department of Environment and Natural Resources

Iloilo City

MINES AND GEOSCIENCES BUREAU Technical Forum

November 22 2010

OUTLINE

• INTRODUCTION

• METHODOLOGY

• RESULTS AND FINDINGS

• APPLICATIONS AND SIGNIFICANCE

• RECOMMENDATIONS

The Philippines has abundant mineral resources

1981 to 1985 - top 5 in gold and top 10 in copper production

MAP AND DATA FROM MGB-DENR

MAJOR ACCOMPLISHMENTS IN THE MINING SECTOR2000 VS 2009

INDICATORS PREVIOUS

(2000)

PRESENT (2009)

estimated

Operating Mines/Mining Projects

- Large/Medium Scale - Small Scale

29

2,649

41

2,343

MINING TAXES/FEES/ CHARGES

P2.65 B P7.84 B

EMPLOYMENT (DOLE) Direct: 110,000

Indirect: 550,000 Direct: 165,000

Indirect: 825,000

GROSS OUTPUT PhP 31.0 B PhP 106.55 B

Seedlings planted (Mining Forest Program)

7,629,004 8,785,089

Area planted (Mining Forest Program)

3,146.44 has 9,834.99 has

Approved Environmental Protection and Enhancement Programs (EPEP)

29 61

SOME MINING CONCERNSLimited data (geology and mineralization), dwindling ore reserves, high cost of prospecting, exploration and mine development

IF MINING ---> ECONOMIC DEVELOPMENTHOW CAN WE HELP IN THE REVITALIZATION OF THE MINING INDUSTRY ?

PROVIDE THE INVESTORS/ ---> RELIABLE DATAMINING COMPANIES EXPLORATION TOOL

ALTERNATIVE SOURCES OF ORE MINERALS

METALLIC MINERAL PRODUCERS

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Year

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MB

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PR

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UC

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COPPERGOLDNICKELCHROMITE

1970s 1980s 1990s 2000 2008

Operating Copper Mines:

PADCAL COPPER MINE (PHILEX)

CARMEN COPPER PROJECT (ATLAS/CCC)

CANATUAN SULPHIDE PHASE PROJECT (TVI)

• PORPHYRY COPPER DEPOSITS - low-grade copper, gold and (or) molybdenum mineralization usually within and around diorites and defined by zones of alteration; provides more than half of the world’s supply for copper and a significant source of gold

• From 1990-1995, 26% of the annual gold production of the Philippines came from porphyry copper deposits

• Copper - electrical materials and machineries, electronics industry, coinage, etc.

• Gold - coinage, jewelry, photography, medical, dental and electronics industry, etc.

Area/Mine Resources/Reserves % Cu g/t Au(million tonnes)

Boyongan 300.00 0.60 1.00

Asiga 26.00 0.36

Tagpura-Kalamatan- 75.60 0.44 0.50Maangob (Batoto)

Amacan 65.00 0.34 0.41

Mapula 78.00 0.40 0.36

Kingking 353.00 0.39 0.44

Southeastern Mindanao - hosts several porphyry copper deposits/ prospects

PORPHYRY COPPER-GOLD MINES

• Philex Mining Corporation PADCAL Copper Mine (as of Dec. 2008):

Proved ore reserves (remaining) - 54.7 million MT

Mine life - ~ 58 yrs (until 2017)

Current no. of employees - 2,478 persons

Taxes and fees paid (2008) - PhP 1.015 Billion

• Kingking Porphyry Copper-Gold Deposit

2 billion lbs. of copper concentrate

4 million oz. of gold

4 million oz. of silver

Value - US $ 14 Billion

Taxes and other fees - > US $ 400 Million

Mine life - ~13-15 yrs

OBJECTIVES

1. ADDRESS THE SCARCITY OF PUBLISHED DATA (geology and mineralization) in a known and profitable mining area

2. TO KNOW MORE ABOUT PORPHYRY COPPER MINERALIZATION IN SOUTHERN PHILIPPINES (characteristics and age of intrusive rocks, hydrothermal system)

3. PROPOSE A GENETIC MODEL ON THE FORMATION OF THE KINGKING DEPOSIT which could provide clues on how to look for porphyry copper deposits

FORMATION OF THE KINGKING PORPHYRY COPPER DEPOSIT

EXPLORATION TOOL FOR PORPHYRY COPPER DEPOSITS

METHODOLOGY

TIOGDAN

KAMPO II

CORE HOUSE BENGUET CORP.

LITHOLOGIC MAP OF THE KINGKING PORPHYRY COPPER DEPOSIT

ALTERATION

Potassic alteration (biotite/k-feldspar) in Biotite Diorite Porphyry and Hornblende Diorite Porphyry

Most of the copper ores are located in the potassic alteration zone

Usual sources of copper and (or) gold - quartz veinlets stockworks and disseminations of copper ores in the diorites

Primary copper ores - bornite and chalcopyrite

Gold is present in chalcopyrite and bornite

A NEW SOURCE OF COPPER ORE IN A PORPHYRY COPPER DEPOSIT?

• BORNITE PODS - bornite + chalcopyrite + calaverite

• 1ST time to be reported in the

Philippines; 2ND in the world after Endeavor Mine in Northparkes, Australia

• Not related to quartz veinlets stockworks or disseminations

• Associated with the Biotite Diorite Porphyry, (brecciated portion)

• Larger compared to other copper ores

NEW!

OLD

BORNITE PODS• Sulfur isotope analysis - ultimate source of

sulfur is identical for bornite pods and sulfides associated with quartz veinlets stockworks

• May be xenoliths, representing sulfide melt from earlier mineralized diorites and volcanics rocks formed by compaction-driven sulfide segregation and filter pressing differentiation

• Suggests multiple stages of mineralization & efficient natural process of concentrating copper ores

CHARACTERISTICS OF MAGMA AND ORE FLUIDS AT THE KINGKING PORPHYRY COPPER DEPOSIT

• Enriched in LREE, depleted in HREE• Mineral chemistry - magnesian

composition, XMg = 0.57 to 0.82 and 0.60 to 0.79, SO3 = 55 wt%

• Dioritic, genetically related, calc-alkaline, adakitic, hydrous, oxidizing

The magma has potential to generate porphyry copper deposits

Fields after Defant and Drummond (1990) and Castillo et al (1999)

• Hot, metal- and sulfur-rich, hypersaline hydrothermal fluid (~400°C and higher)

• Forms potassic alteration, depositing most of the copper and gold

NEW AGE DATA FOR INTRUSIVE ROCKS IN SOUTHEASTERN MINDANAO

Sample Spike Potassium Rad. 40

Ar K-Ar age Non-rad. 40

Ar

No. No. (wt. %) (10-8 cc STP/g) (Ma) (%)

A-17-1E S40-341 0.366 ± 0.018 38.61 ± 0.84 27.0 ± 1.5 46.4

KKII-11-1A S40-342 0.415 ± 0.021 18.37 ± 0.63 11.37 ± 0.69 63.8

Mineralization can also occur in specific time frames

Oligocene (33.7-23.8 million years ago) to Miocene (23.8-5.3 million years ago)

Age of rocks/mineralization in an area --> may search for mineralization in rocks of the same age

31.44 0.78 Ma46.14 1.58 Ma27.0 1.5 Ma17.49 0.43 Ma11.37 0.60 Ma

27.0 1.5 Ma

11.37 0.60 Ma

FORMATION OF THE KINGKING PORPHYRY

COPPER DEPOSIT

A. Dioritic, calc-alkaline, hydrous, oxidizing and adakitic magma formed HDP and DP

B. Early mineralization episode

C. Intrusion of BDP

D. Formation of bornite pods and fine-grained matrix

E. Hydrothermal alteration and deposition of sulfides

F. Later intrusion of dikes

USING RESULTS FROM THIS STUDY, THEN…

WHEN LOOKING FOR A PORPHYRY COPPER DEPOSIT:

A. PRIORITIZE OLIGOCENE TO MIOCENE QUARTZ DIORITE, HORNBLENDE DIORITE, BIOTITE DIORITE PORPHYRY

B. CHECK OR RE-CHECK DRILL CORE DATA/BRECCIATED PORTION OF DIORITE FOR PRESENCE OF BORNITE PODS --> CALCULATE VOLUME

C. POLYPHASE HYPERSALINE FLUID INCLUSIONS AND CALC-ALKALINE, HYDROUS AND OXIDIZING MAGMA

DIORITE (BIOTITE DIORITE

PORPHYRY)

OLIGOCENE TO MIOCENE AGE

FAULT/FRACTUREZONE

QUARTZ VEINLETSSTOCKWORKS

POTASSIC ALTERATION ZONE

+ + +

SIGNIFICANCE:

1. Provide much needed and new data on the geology (diorites, biotite diorite porphyry) and mineralization (veinlets/disseminations/bornite pods) and age of diorites (Oligocene-Miocene) in Southeastern Mindanao

2. Identified new and possible alternative source of copper and gold (bornite pods/clots)

3. Outlined an easy to use exploration tool for porphyry copper deposits

4. Results were published in international journals and presented in international conferences

RECOMMENDATIONS

Further study on other aspects of porphyry copper mineralization especially and other porphyry copper deposits

ACKNOWLEDGMENTS

• Japanese government (Ministry of Education, Culture, Sports, Science and Technology

• Asso. Prof. A. Imai and Prof. K. Watanabe, Prof. T.Hirajima and Prof. K. Jinno

• Econ. Geol. Laboratory, Kyushu University and RWG, NIGS, UP Diliman

• Prof. Itaya, Geochronological Laboratory, Okayama Science University

• Electron Probe Microanalysis, University of Tokyo

• Benguet Corporation, Philco Mining, Privatization and Management Office, Apex Mining Company Limited, Philex Mining

• DENR, MGB Central Office and Regional Offices No. XI and VI

• PCIERD-DOST

• People of Compostela Valley and Davao City