1. 60 T ü rkiye Jeoloji Kurultayi Exploration for Skarn Deposits Larry Meinert Department of Geology Smith College Northampton, MA 01063 USA Email: Lmeinert@smith.edu

3. Skarns and Skarn Deposits 1)General processes of skarn formation 2)Mineralogy, petrology, & tectonic setting 3) Examples of major skarn deposits: Antamina - Peru Ertsberg District - Irian Jaya

8. Depth of Formation - W Skarns Tonnage and grade63 Mt of 0.95 WO3 Igneous Compositioncalc-alkaline granodiorite to granite Igneous geometryc.g. batholith with pegmatite, megacrysts Igneous alterationFresh, minor myrmekite, Ca endoskarn MetamorphismExtensive metamorphic aureole (km) with high T mineral assemblages and reaction skarns (bimetasomatism)

10. Pine Creek, CA W skarn Granodiorite Skarn Marble

11. Sub-calcic garnet Calcic garnet & pyroxene

12. Scheelite Sub-calcic garnet veins

13. Depth of Formation - Cu Skarns Tonnage and grade500 Mt of 0.8% Cu Igneous Compositioncalc-alkaline diorite to quartz monzonite Igneous geometrym.g. to porphyritic stocks and dikes Igneous alterationK-silicate, sericitic, epidote endoskarn MetamorphismVariable metamorphic aureole (cm to km) lacks high T mineral assemblages

21. Distal Features - Zn Skarns Tonnage and grade50 Mt of 10% Zn, 5% Pb, 150 g/t Ag Igneous Compositiongranodiorite to granite to unknown Igneous geometrybatholith to stocks to dikes to unknown Igneous alterationExtensive epidote±garnet endoskarn MetamorphismBleaching and recrystallization, no high T metamorphic aureole

32. Skarns and Skarn Deposits 1)General processes of skarn formation 2)Mineralogy, petrology, & tectonic setting 3) Examples of major skarn deposits: Antamina - Peru Ertsberg District - Irian Jaya

40. Skarns and Skarn Deposits 1)General processes of skarn formation 2)Mineralogy, petrology, & tectonic setting 3) Examples of major skarn deposits: Antamina - Peru Ertsberg District - Irian Jaya

41. Skarn deposits of Peru

42. Antamina Cu-Zn skarn, Peru 1)> 1 billion tons of Cu-Zn resource 2)~ Barren porphyry intrusive center 3) Abundant endoskarn 4) Classic skarn zonation

48. Quartz monzonite porphyry

49. Endoskarn Porphyry

51. Green garnet skarn

52. Garnet Pyroxene

53. Garnet Wollastonite

54. Marble Garnet skarn

55. Calcite ± wollastonite veining Gray marble

56. Fluid escape structures Marble

57. What if Turkey had as many ore deposits as Peru?

58. Turkey ore deposit density by analogy with Peru

59. Ertsberg Cu-Au district, Irian Jaya 1)> 2 billion tons of Cu-Au reserves, largest Cu-Au resource on Earth 2)~ Mineralized porphyry intrusive centers 3) No endoskarn 4) Classic skarn zonation

63. Tembagapura mine camp housing for ~ 7,000 workers

64. Tram car carries 50-100 workers at a time up to mine site

65. Mine site at 4,000 m Usually is in clouds

66. Tram station at mine site, looking down to mill site in valley

67. Tram station Original Ertsberg ore body

68. Tram station

69. Tram station

70. Yellow Valley syncline Puncak Jaya 5000 m

72. Grasberg pit

76. Marble Diorite Endoskarn

78. Mt-cp-bn

80. Mg skarn with olivine, monticellite, vesuvianite

81. Mg skarn with retrograde serpentine veins

85. Biotite hornfels Garnet veinPyroxene envelope/vein

86. Red-brown garnetAnhydrite Cp

87. Red-brown garnetPyroxene

88. Pyroxene-chalcopyrite skarn

89. Distal diopsidic pyroxeneAnhydriteLate Fe-rich pyroxene

90. Fluid escape structures in marble

91. GarP>GPyxMarble Fluid escape structures