Diagenetic history of Ordovician and Devonian oil ... - Geology Ontario

CHAPTER 5 DISCUSSION OF CAP DOLOMITE, FRACTURE-RELATED
DOLOMITE AND DEDOLOMTTE
Dolomitization.................................................................................................
1) Does the cap dolomite and fracture-related dolomite result from
the same solution or different solutions?.....................................................................62
2) If different, which of the cap dolomite or fracture-related dolomite comes
first and what is the effect of one on the other?..........................................................63
3) What does the geochemistry reveal of the nature of the fracture-related
dolomitizingsolution?...................................................................................................64
4) Did fracture-related dolomitization result from hydrothermal brines?.......................64
5) If hydrothermal, does the dolomitizing fluid come from above or below?..................66
Trenton-Blue Mountain Contact and Associated Cap Dolomite....................................69
Dolomitized Grainstone in the OGS-82-2 Well
(Located Away From the Fractures)........................................................................71
Summary of Dolomitization..............................................................................................72
Comparison of Middle Ordovician Dolomite in Ontario and Michigan...........................73
Dedolomitization...............................................................................................................75
Dedolomitization Environments.................................................................................75
Discussion of Burial Dedolomitization ......................................................................76
Geochemistry of Dedolomitization.............................................................................77
Discussion of Calcitization of Anhydrite .........................................................................78
CHAPTER 6 SUMMARY AND CONCLUSIONS
Summary............................................................................................................................8
Future Work......................................................................................................................82
Conclusions.......................................................................................................................83
REFERENCES ................................................................................................................85
PLATES ..............................................^^
APPENDIX l SUMMARY OF CORE DATA..........................................................128
APPENDIX 2 DOLOMITE TYPES...........................................................................131
APPENDIX 3 CARBON AND OXYGEN ISOTOPE DATA.................................133
APPENDIX 4 MICROPROBE SAMPLES AND DATA........................................136
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