AUTHORS Rick Wierzbicki  EnCana Corporation, 150 9th Avenue SW, P.O. Box 2850, Calgary, Alberta, Canada T2P 2S5; richard.wierzbicki@encana.com Rick Wierzbicki earned his B.Sc. degree from the University of Alberta in 1980. He worked for Shell Canada Resources from 1980 to 1984. Since then, he has worked for PanCanadian Petroleum Limited, now EnCana, as an explo- ration and development geologist. He worked on the development plan for the Deep Pa- nuke Project from 2000 to 2004. His interests are in carbonate sedimentology and reservoir characterization. He is a member of the Ca- nadian Society of Petroleum Geologists, AAPG, and the Association of Professional Engineers, Geologists, and Geophysicists of Alberta. Jeffrey J. Dravis  Dravis Geological Ser- vices, 4133 Tennyson, Houston, Texas 77005; jdravi@rice.edu Jeffrey J. Dravis is a consulting carbonate geologist located in Houston and an adjunct professor at Rice University. His company, Dravis Geological Services, conducts technical projects for oil and gas companies, specializing on carbonate diagenesis and porosity evolu- tion and play development. Dravis Interests, Inc., presents applied in-house seminars and a field course to Caicos platform (>125 pre- sented to date). Ihsan Al-Aasm  Department of Earth Sciences, University of Windsor, 401 Sunset, Windsor, Ontario, Canada N9B 3P4 Ihsan Al-Aasm earned his B.Sc. and M.Sc. de- grees from the University of Baghdad and his Ph.D. from the University of Ottawa. He worked at the Geological Survey of Iraq from 1978 to 1980 and as a postdoctoral fellow from 1984 to 1986, and then, he worked as as- sistant professor (1986 – 1988) at the Univer- sity of Ottawa. He joined the University of Windsor in 1988, and he is now a full professor and head of the Department of Earth Sciences, University of Windsor. His principal area of research is on petrologic and chemical attributes of carbonate and siliciclastic diagenesis, dolo- mitization, and environmental geochemistry. He acted as an associate editor for the Journal Burial dolomitization and dissolution of Upper Jurassic Abenaki platform carbonates, Deep Panuke reservoir, Nova Scotia, Canada Rick Wierzbicki, Jeffrey J. Dravis, Ihsan Al-Aasm, and Nancy Harland ABSTRACT A large gas reservoir was discovered in the previously unproduc- tive Jurassic-aged Abenaki carbonate margin in 1998. Most of the reservoir porosity is developed in dolostones. These dolostones re- placed preexisting wackestones, packstones, and grainstones(?) asso- ciated with reefal and adjacent depositional environments. Many dolomites were subsequently recrystallized or dissolved, account- ing for much of the preserved secondary porosity. Subsequent frac- turing helped enhance reservoir permeabilities. Enhanced petrographic techniques established that dissolution of previously dolomitized fabrics generated much of the secondary porosity in these dolostones. Diffused plane-polarized light revealed relict grains and textures invisible with standard microscopic ob- servations. Petrographic and geochemical observations also confirmed that dissolution occurred under deep-burial conditions after in- cipient pressure solution. Dissolution was not confined to the centers of dolomitized grains, as is commonly seen when remnant calcitic grains dissolve out dur- ing the advanced stages of replacement dolomitization. Instead, dissolution was random within relict grains, as isolated dolomite crystals were also variably dissolved. The geochemistry of these dolomites and associated late-stage calcites implied precip- itation from basinal hot fluids, as well as hydrothermal fluids. Later diagenetic fluids, either acidic or calcium rich, or perhaps both at different times (based on associated mineralization), seemingly pro- moted dolomite dissolution. The presence of tectonic fractures and stylolites, helium gas, and faults observed in seismic data implied that dolomitization and subsequent dissolution along the Abenaki platform margin were AAPG Bulletin, v. 90, no. 11 (November 2006), pp. 1843 – 1861 1843 Copyright #2006. The American Association of Petroleum Geologists. All rights reserved. Manuscript received April 19, 2005; provisional acceptance September 19, 2005; revised manuscript received January 26, 2006; final acceptance March 20, 2006. DOI:10.1306/03200605074