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Clay mineral & alteration.pdf
- 1. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Clay Minerals, Alteration Clay Minerals, Alteration & & Terry’s pH Terry’s pH- -Temperature Table Temperature Table Kaylene Camuti Lantana Exploration Pty Ltd Additional data provided by: Greg Corbett - Corbett Geological Services Jane Harvey, Juli Hugenholtz & Doug Young - ActivEX Limited
- 2. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Clay Minerals, Alteration Clay Minerals, Alteration & & Terry’s pH Terry’s pH- -Temperature Table Temperature Table Kaylene Camuti Lantana Exploration Pty Ltd Additional data provided by: Greg Corbett - Corbett Geological Services Jane Harvey, Juli Hugenholtz & Doug Young - ActivEX Limited
- 3. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Skarn Potassic Propylitic Outer Propylitic Phyllic Argillic Advanced Argillic Common Alteration Mineralogy in Hydrothermal Systems Common Alteration Mineralogy in Hydrothermal Systems Terry Leach 1995
- 4. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Temperature Temperature - - K activity Diagram K activity Diagram 500 400 300 200 100 1 2 3 4 5 log(aK+/aH+) 100 MPa Quartz Present K-Feldspar Muscovite Andalusite Pyrophyllite Kaolinite (from Inoue, 1995, after Sverjensky et al., 1991) Dickite at higher temps Illite at lower temps
- 5. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 6. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Outline Outline • Why identify alteration minerals & assemblages? • Characteristics of alteration minerals & assemblages illustrated in the pH- temperature table • Using the table to interpret alteration minerals.
- 7. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Why identify alteration minerals? Why identify alteration minerals? • The chemistry and structure of alteration minerals are a response to their conditions of formation – so the minerals and mineral assemblages provide information on hydrothermal conditions. • The minerals typically occur in zones that reflect changing conditions of formation. • The recognition of alteration mineral zoning can help identify hydrothermal fluid channelways and may provide vectors to mineralisation.
- 8. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Corbett & Leach Low Low Sulphidation Sulphidation Systems Systems
- 9. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 chlorite-rich smectite-rich illite-rich quartz-alunite rich kaolinite-rich v u g g y m ineralis ed q u a r tz u nalt ered q u a r tz latite smectite-chlorite z o n e illite- kaolinite z o n e q ua rtz - alunite z o n e (adapted from Steven & Ratte, 1960, in Hayba et al., 1985) High High Sulphidation Sulphidation Alteration Alteration - - Summitville Summitville
- 10. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Characteristic Characteristic Alteration Minerals & Assemblages Alteration Minerals & Assemblages • Some alteration minerals or alteration assemblages are characteristic of particular temperature & fluid pH conditions. • The pH – temperature table has been subdivided into alteration types with diagnostic mineral assemblages.
- 11. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Terry Leach 1995 Argillic Argillic pH ~ 4 pH ~ 4 - - 6 6 Phyllic Phyllic pH ~ 5 pH ~ 5 - - 6 6 Advanced Advanced Argillic Argillic pH < 4 pH < 4 Propylitic Propylitic pH ~ 6 + pH ~ 6 + Potassic Potassic pH ~ 7 + pH ~ 7 +
- 12. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Silicate Alteration Minerals Silicate Alteration Minerals - - characteristics characteristics kaolin minerals kaolin minerals Al, Al, Si Si, OH , OH H H2 2O O pyrophyllite pyrophyllite Al, Al, Si Si, OH , OH andalusite andalusite Al Al Si Si silica minerals silica minerals Si Si +/ +/- - H H2 2O O poorly crystalline poorly crystalline quartz quartz Si Si crystalline crystalline illite illite – – smectite smectite K, Al, Mg, Fe, K, Al, Mg, Fe, Si Si, OH , OH H H2 2O O muscovite muscovite K, Al, Mg, Fe, K, Al, Mg, Fe, Si Si, OH , OH chlorite minerals chlorite minerals Fe, Mg, Al, Fe, Mg, Al, Si Si, OH , OH H H2 2O O epidote epidote + amphibole + amphibole minerals minerals Ca, Fe, Mg, Al, Ca, Fe, Mg, Al, Si Si, OH , OH biotite biotite K, Fe, Mg, Al, K, Fe, Mg, Al, Si Si, OH , OH pyroxene pyroxene Ca, Mg, Fe, Ca, Mg, Fe, Si Si increasing fluid pH increasing fluid pH increasing temperature increasing temperature
- 13. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Using the table to interpret alteration assemblages Using the table to interpret alteration assemblages in mineral exploration in mineral exploration
- 14. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 XRD Summary Results XRD Summary Results – – HS System HS System - - table table minor Diaspore trace? trace - minor trace? trace? Feldspars trace trace? Rutile minor Tourmaline minor- major minor minor trace minor minor Pyrite dom major trace – minor dom dom major-dom dom Quartz minor- (major) trace? Alunite Group major Chlorite dom major ML Illite- Smect major major Hydrated Illite major trace-minor? major weak trace? major major Illite trace minor trace weak trace ? Kaolin Group major major-dom Pyrophyllite 26 25 24 23 22 21 20 Minerals
- 15. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 PIMA PIMA – – list of alteration minerals list of alteration minerals Smectite Fine-gr'd Porphyry? Pale grey, fine-grained, hard, with hematite fractures Outcrop BM1004A Kaolinite Alunite Outcrop at top (v rocky), pale alteration with yell-brown coating Outcrop BM1003C Kaolinite Alunite Outcrop at top (v rocky), pale alteration with yell-brown coating Outcrop BM1003B Kaolinite Pyrophyllite Fine-gr'd Porphyry? Pink-Red alteration (hard) Outcrop BM1002B Pyrophyllite Alunite Kaolinite Fine-gr'd Porphyry? Red alteration (Fine-grained, hard) Outcrop BM1002A Kaolinite Alunite Qtz Porphyry? Very red, fine-grained siliceous Outcrop BM1001E Topaz Pyrophyllite Kaolinite Silicified Qtz porphyry? Pinky-grey with diss hematite spots Outcrop BM1001D Kaolinite Sericite Pale green altd fragmental(?) volcanic Quarry DB006C (trace Sericite) Kaolinite Pale clay altd volcanic(?) with local ferruginous stain Quarry DB006B Kaolinite Sericite Very fine-gr'd porphyry, pink Quarry DB006A Sericite Felspar Porphyry, east of silica zone, pink with sericite Outcrop DB005B Kaolinite Sericite Felspar Porphyry, east of silica zone, pink with sericite Outcrop DB005A Kaolinite Sericite Pink porphyry, sericite altered Outcrop DB004C Kaolinite Sericite Pink porphyry, sericite altered Outcrop DB004A (trace Topaz) Kaolinite Dickite Very pale, clay altered Outcrop DB003C Topaz Kaolinite Dickite Very pale clay altered Outcrop DB003B Kaolinite Dickite Very pale clay altered Outcrop DB003A Kaolinite Dickite Fine-gr'd porphyry? very pale alteration, sparse hematite microfractures Outcrop DB001B Dickite Kaolinite Fine gr'd porphyry? pale brown alteration Outcrop DB001A Mineral 3 Mineral 2 Mineral 1 Description Sample Type Sample ID
- 16. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Drill Log Drill Log - - descriptive descriptive Pervasive dark green Chlor alteration. s p 160.2 153.2 Strong clay alteration of primary KFs. Local disseminated pink secondary KFs. s d 89.3 83.8 Strong Chl and Ser - texturally destructive i p 83.5 83 Pervasive strong Chl replacing KFs & Hblende s d 40.8 39.7 Weakly disseminated KFs alteration with locally developed moderate Chl. w d 32.6 24.7 Weakly disseminated KFs alteration with locally developed moderate Chl. m d 24.7 21.5 Description Int Style To From
- 17. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 XRD Summary Results XRD Summary Results – – HS System HS System minor Diaspore trace? trace - minor trace? trace? Feldspars trace trace? Rutile minor Tourmaline minor- major minor minor trace minor minor Pyrite dom major trace – minor dom dom major-dom dom Quartz minor- (major) trace? Alunite Group major Chlorite dom major ML Illite- Smect major major Hydrated Illite major trace-minor? major weak trace? major major Illite trace minor trace weak trace ? Kaolin Group major major-dom Pyrophyllite 26 25 24 23 22 21 20 Minerals
- 18. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 20 20
- 19. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 XRD Summary Results XRD Summary Results – – HS System HS System minor Diaspore trace? trace - minor trace? trace? Feldspars trace trace? Rutile minor Tourmaline minor- major minor minor trace minor minor Pyrite dom major trace – minor dom dom major-dom dom Quartz minor- (major) trace? Alunite Group major Chlorite dom major ML Illite- Smect major major Hydrated Illite major trace-minor? major weak trace? major major Illite trace minor trace weak trace ? Kaolin Group major major-dom Pyrophyllite 26 25 24 23 22 21 20 Minerals
- 20. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 20 20 21 21
- 21. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 XRD Summary Results XRD Summary Results – – HS System HS System minor Diaspore trace? trace - minor trace? trace? Feldspars trace trace? Rutile minor Tourmaline minor- major minor minor trace minor minor Pyrite dom major trace – minor dom dom major-dom dom Quartz minor- (major) trace? Alunite Group major Chlorite dom major ML Illite- Smect major major Hydrated Illite major trace- minor? major weak trace? major major Illite trace minor trace weak trace ? Kaolin Group major major-dom Pyrophyllite 26 25 24 23 22 21 20 Minerals
- 22. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 20 20 21 21 22 22
- 23. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 20 20 21 21 22 22 23 23 26 26 ?
- 24. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 chlorite-rich smectite-rich illite-rich quartz-alunite rich kaolinite-rich v u g g y m ineralis ed q u a r tz u nalt ered q u a r tz latite smectite-chlorite z o n e illite- kaolinite z o n e q ua rtz - alunite z o n e (adapted from Steven & Ratte, 1960, in Hayba et al., 1985) High High Sulphidation Sulphidation Alteration Alteration - - Summitville Summitville
- 25. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 26. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 27. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 28. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 29. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 Blairmore Blairmore – – Demonbanga Demonbanga Alteration Minerals from PIMA study Alunite Pyrophyllite Dickite Kaolinite Diaspore Topaz Sericite Illite-Smectite Smectite The minerals occur in a variety of assemblages.
- 30. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 pyrophyllite pyrophyllite- -alunite alunite
- 31. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 kaolinite kaolinite- -pyrophyllite pyrophyllite- -topaz topaz
- 32. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 pyrophyllite pyrophyllite- -kaolinite kaolinite- -diaspore diaspore
- 33. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 dickite dickite- -kaolinite kaolinite- -topaz topaz
- 34. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 sericite sericite- -kaolinite kaolinite
- 35. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 montmorillonite montmorillonite- -kaolinite kaolinite
- 36. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 dickite dickite alunite alunite
- 37. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8
- 38. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 39. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 40. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008
- 41. Lantana Exploration Lantana Exploration- - TLS Oct 2008 TLS Oct 2008 1 1 2a 2a 2b 2b 2c 2c 3 3 1. Porphyry high sulphidation systems 2. Structural & lithological high sulphidation systems 2a. Silica Core 2b. Deep peripheral zones 2c. Shallow peripheral zones 3. Descending cool acid sulphate fluids