Selección del Segmento de Mercado

future work

This research has revealed new insights into the formation of the Offset Dykes of the North Range; however, there are many questions that remain unanswered. Is the single injection and flow differentiation model applicable to all of the Offset Dykes, or if it specifically applies to the Foy? As discussed briefly above, observations of the Trill, Parkin and Worthington Offset Dykes could support the model. However, dykes such as the Hess that are concentrically oriented and contain very little IQD likely were emplaced under different conditions, as discussed in Chapter 2. Future studies on the various Offset Dykes should take these results into consideration when attempting to discern the

If the Pele was emplaced later than the other Offset Dykes from a more evolved SIC melt – as suggested herein – then why is there no evidence of Offset Dykes cutting across the SIC? And what mechanism was responsible for causing dyke emplacement so late in the crater modification stage?

The relationship between the North Range and the South Range Offset Dykes is another problem that has not been addressed here. Lightfoot et al. (1997) documented the geochemical differences between the North and South Ranges, and attributed this

difference to the assimilation of the local country rocks – which are different in the North and South Ranges. However, the question of why the SIC and Offset Dykes of the North and South Ranges differ is one that has not been sufficiently addressed in the current literature.

Perhaps the most significant question is why Offset Dykes are only found in large impact structures. Smaller complex craters such as the Ries (Osinski 2004) and Haughton

(Osinski 2005) are not known to be associated with impact-melt dykes of this scale. The only comparable example to the Offset Dykes are the Vredefort Granophyre dykes (Reimold and Gibson 2006), which are similarly large (up to ~50 m wide) impact-melt dykes that are rich in inclusions towards the centre of the dykes. This suggests that the Offset Dykes are a unique feature of very large impact structures. A comparison study of the Vredefort Granophyre and Sudbury Offset Dykes would further our understanding of how such dykes form in – and are only found in – large impact structures.

5.5

References

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Bhattacharji, S., and Smith, C.H. 1964. Flowage differentiation. Science, 145: 150–153. Coulter, A.B. 2015. The underlying structural controls of the Whistle-Parkin and Trill

Offset Dykes in the Sudbury Impact Structure. M.Sc. thesis, Department of Earth Sciences, University of Western Ontario, Ontario, Canada.

Grant, R.W., and Bite, A. 1984. Sudbury quartz diorite offset dykes. In The Geology and Ore Deposits of the Sudbury Structure. Edited by E.G. Pye, A.J. Naldrett and P.E. Giblin. Ontario Geological Survey Special Volume 1, Ministry Natural

Resources, Toronto. pp. 275–300.

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Lightfoot, P.C., and Farrow, C.E.G. 2002. Geology, geochemistry, and mineralogy of the Worthington Offset Dyke: A genetic model for Offset Dyke mineralization in the Sudbury Igneous Complex. Economic Geology, 97: 1419–1446.

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Canada. Meteoritics and Planetary Science, 40(12). Pao, R.H.F. 1961. Fluid mechanics. John Wiley & Sons, N.Y.

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cratering and the evolution of the Witwatersrand Basin. Chemie der Erde, 66: 1– 35.

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Smith, D.A., Bailey, J., and Pattison, E.F. 2013. Discovery of New Offset Dykes and Insights into the Sudbury Impact Structure (abstract). In LPI Contributions 1737. p. 3090.

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Tuchscherer, M.G. 1998. The petrology, geochemistry, and emplacement of the Foy Offset Dyke, Sudbury impact structure. M.Sc. thesis, Department of Earth Sciences, University of New Brunswick, Fredericton, New Brunswick, Canada. Vand, V. 1948. Viscosity of solutions and suspensions. The Journal of Physical

Appendices

Appendix A: List of samples. Coordinates are recorded using NAD 83, in Zone 17T. Data available in ‘Pilles - Appendices A to G.xlsx’.

Appendix B: Results of electron microprobe analyses of plagioclase. Acquired at McGill University using a JXA JEOL-8900L electron microprobe. Data available in ‘Pilles - Appendices A to G.xlsx’. Names of the spot analyses reflect the original sample names. Refer to the ‘Notes’ column in Appendix A.

Appendix C: Results of electron microprobe analyses of sulfides. Acquired at Western University using a JXA-JEOL-8530F field-emission electron microprobe. Data available in ‘Pilles - Appendices A to G.xlsx’.

Appendix D: Results of geochemical analyses. Acquired by ALS Minerals using ICP- MS, ICP-AES and Fire Assay. Data available in ‘Pilles - Appendices A to G.xlsx’.

Appendix E: Location of transects made along the Foy and Hess Offset Dykes where clast orientation, lithology and abundance was recorded. Data available in ‘Pilles - Appendices A to G.xlsx’.

Appendix F: Abundance and lithologies of clasts along the transects listed in Appendix G. Totals for each row reflect the number of clasts visible in a m2 area. Data available in ‘Pilles - Appendices A to G.xlsx’.

Appendix G: Long-axis orientation of clasts along the transects listed in Appendix I. Each square consists of a m2 _{area. Data available in ‘Pilles - Appendices A to G.xlsx’.}

Appendix H: Photomicrographs. Data available in ‘Pilles – Appendix H - photomirographs.zip’.

Appendix I: Backscatter electron images, EDS and WDS spot analyses, element maps. Acquired at Western University using a JXA-JEOL-8530F field-emission electron microprobe. Data available in ‘Pilles - Appendix I – Microprobe images.zip’.

Appendix J: Trench maps produced during this study, at 1:50 scale. Clasts > 30 cm in diameter were mapped. Coordinates listed in UTM NAD83. Data available in ‘Pilles – Appendix J – trench maps.pdf’.

Curriculum Vitae

Name: Eric Pilles

Post-secondary University of Western Ontario

Education and London, Ontario, Canada

Degrees: 2008-2012 B.Sc.

Honours and Western Graduate Research Scholarship

Awards: 2013-2015

Dean’s Honor List 2010, 2012

The Dr. Harvey Hunter Memorial Award 2011

Related Work Teaching Assistant

Experience The University of Western Ontario 2012-2016

Research Assistant

The University of Western Ontario 2012-2016

Intern

Mitacs Accelerate 2013-2015

Publications:

Pilles, E., Osinski, G. R., Bailey, J., and Smith, D. 2014. Emplacement of multiple quartz diorites within the Foy offset dyke at the Sudbury Impact Structure, Canada [Abstract No. 153]. In proceedings of the 2014 GAC MAC Annual Meeting.

Pilles, E., Osinski, G. R., Bailey, J., and Smith, D. 2014. Outward Emplacement of the Foy Offset Dyke at the Sudbury Impact Structure, Canada - Evidence from the Variation in Inclusions Along Strike (abstract). In proceedings of the 2014 GSA Annual Meeting. Pilles, E., Osinski, G. R., Grieve, R. A. F., Bailey, J., and Smith, D. 2015. Exploring the origin of the offset dykes at the Sudbury impact structure, Canada (abstract). In