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
0
2
4
6
8
10
12
14
16
18
201
97
51
97
61
97
71
97
81
97
91
98
01
98
11
98
21
98
31
98
41
98
51
98
61
98
71
98
81
98
91
99
01
99
11
99
21
99
31
99
41
99
51
99
61
99
71
99
81
99
92
00
02
00
12
00
22
00
32
00
42
00
52
00
62
00
72
00
8
Year
NU
MB
ER
OF
PR
OD
UC
ER
S
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
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