University of Alberta South Fields Area, West-Central
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UNIVERSITY OF ALBERTA ICHNOLOGY AND PALAEOENVIRONMENT OF THE LOWER TRIASSIC MONTNEY FORMATION, KAYBOB AND KAYBOB SOUTH FIELDS AREA, WEST-CENTRAL ALBERTA BY DEPvllAN J. C.ROBBINS O A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science Department of Earth and Atmospheric Science Edmonton, Alberta Fall, 1999 National Library Bibliothèque nationale If1 of Canada du Canada Acquisitions and Acquisitions et Bibliographie Services services bibliographiques 395 Wellington Street 395. rue Wdlingtori Ottawa ON Kt A ON4 OitawaON KlAûN4 Canada Canada The author has granted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive permettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or seil reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. ia forme de microfiche/film7de reproduction sur papier ou sur format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fiom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. This thesis is dedicated to three people: Firstly to my parents, Chris Robbins and Marijke Hurkem. 1 can't imagine asking for better people to call Mom and Dad. Secondly, to my grandmother Wihelmina Hurkens, who passed away after this thesis study began. No one could have sliown greater strength in the face of adversity. Thirty-nine core and more than 300 well logs examined from the Lower Montney Formation around the Kaybob and Kaybob South hydrocarbon fields exhibited fif- teen facies grouped into three facies associations, two siliciclastic and one bioclastic. Clastic Association One (CA1) comprised three gradationally interbedded facies of interlarninated very fine sand and silt that exhibit a distinct tidal and seasonal in- fluence on sedimentation. It was characterized by an impoverished, but locally abundant, assemblage of 5 major and 6 rare ichnogenera, predorninated by Lingzdichnrrs. Locally intercalated or overlying CA1 is Clastic Association Two (CM), com~risedof 5 facies indicative of episodic deposition and penecontemporaneous alteration of sediments. The Bioclastic Association, which has a locally erosive and discordant morphology, comprises 5 facies dominated by coarse shell fragments and rninor intercalated clastics. Two additionai facies of limited distribution were not assigned to a facies association. CA1 is interpreted as the deposits of a tidally influenced, seasonally active delta front. Ichnofossils of this association exhibit characteristics consistent with a sheltered, salinity- and oxygen-stressed environment. CA2 beds occurring withïn CA1 represent a mix of autocyclic and allocyclic perturbations of ambient, stressed deltaic setting. Thicker accumulations of CA2 that overlie CA1, and locdy exhibit lateral equivalence with the Bioclastic Association, represent a barrier-bar-tidal in- let system. Intemal stratigraphy of the Montney in this area is difficdt to decipher. How- ever, two locally mappable units were identified. Both exhibit a channel-constrained morphology. A tower, sandy Channel within CA1 represents a possible distributary mouth. Sinuous, elongate isopach thicks in the Bioclastic Association represent tidai inle t channels. Acknowledgements At the most forma1 level 1 would like to thank my supervisory cornmittee: my supervisor Dr. S. George Pemberton and Doctors J. Lerbekmo and D. Craig. They gave a fair and (dare 1 Say it?) friendly treatment to a relative unknown. 1 would also like to thank Dr. Pemberton and the National Sciences and Engineering Research Council (NSERC Operating Grant No. A0816) for funding this project. 1 must first and foremost thank my supervisor George Pemberton. He had the patience and generosity to see past a rocky start and carry through to a happy ending. Without his tolerance and support this thesis could not have happened and 1would not be the scientist that 1 am (or hope 1 can be). If 1 cmlive up to half the example George has set for me, 1'11 be an endlessly happy man. 1 would also like to thank Dr. Ron K. Pickerill, my mentor and Bachelor's supervisor at the University of New Brunswick, who showed me that there was a whole field with endless possibilities called Ichnology, and with that probably shaped the rest of my career. What can be said about a person who can redirect 17 years of obsessive fixation on dinosaurs into a field that focuses on worm tunnels, bug tracks and invertebrate droppings ... and feel üke it was the best choice that could ever have been made? AU that cornes to my mind is a fervent and honest "Thank yozr !" This thesis could also never have been achieved without the constant and active support of my parents. They started it all with a firm finger pointing to the Library when a Cyear old drove them mad with questions about dinosaurs, and never thought to send me in another direction when that expanded to include all things geological as the years went by. They never once tired of encouraging me when things seemed grim or insurmountable. Thanks are also due to them also for giving me a solid boot to the backside (metaphorically speaking, of course!) when I needed it, which was more often than 1, or anyone else, could ever have wanted. The dedication says it au. Thanks awfully to al1 the guys I've had the honour to work with in the Ichnology Research Croup at the University of Alberta. They tolerated a guy that a t times probably seemed like a semi-recluse, and they offered uncountable insights into both geology and life in general: Sue Gordichuk (George's tireless secretas: who does more for us au, in the background, than we may ever know), Murray Gingras, Arjun Keswani, Yaojun Han and Jason Lavigne @oth of whom 1 foilowed here from UNB), John-Paul Zomeveld (another rocky start that turned out well in the end), Errin Kimball, Ian Armitage, Chad Harris, Glenn Sdimidt, Steve Hubbard, Jason Frank, Tom Saunders, Je£f Reinprecht and Eric Hanson. 1 would particularly like to thank Emin, Ian and Chad for their helpful comments on my thesis when thùigs were down to the wire and deadlines loomed threateningly. Special thanks are owed to Murray and Arjun. Murray was a good friend from the start, taking me on a fishing trip witha week of my arriva1 in Aiberta. Not once did he fail to give a pat on the back, a reassuring thumbs-up, or blunt assessment when it was needed. His insights and comments on both the ideas and drafts of the thesis as they evolved were invaluable. He never grudged me (as far as 1 can tell!) a share of his tirne, his cache of alcohol, a Little cash if it was needed, or his opinions, about which he is far too modest. Aqun was a solid friend as soon as we got to know each other, and someone who could be counted upon to erase preconceptions or offer a whole new perspective on a problem. He has always been willing to spend a couple of hours thrashing out a philosophical issue, staring down a thin-section, or just diatting about the time of day. 1 would also like to thank those people who helped make my sojourn in Edmonton an enjoyable experience. First, 1 must thank Theresa and the rest of George's family for all the wonderful barbecues and dinners. Nobody 1 know pub up a better and more generous spread for a bunch of stawing graduate students: shrimp rings for people who would be happy with hot dogs. Bless them. 1 would also like to thank my various roommates from the past four years, particularly Nick Spyksma, Al and Madeleine Namit, Murray Gingras, Val Slowiak, and John Day and David Catonio. They aii put a roof over my head, put up with my company, and accepted my (at thes) spotty income (truly have 1 learned the meaning of "feast or famine"!). 1camot imagine that two pages have even begun to cover al1 the thanks, large and small, due to those that made the last four years both possible and enjoyable. To all those whom 1may have managed to miss, 1offer my apologies and thanks for both their help and their understanding. TABLE OF CONTENTS PAGES CHAPTER 1 INTRODUCTION .......................... ...................................................................... 1 Introductory Remarks ........................................................................................... 1 General Stratigraphy ............................................................................................. 1 Study Area ...............................................................................................................3 Database and Methods .......................................................................................... 5 CHAPTER 2 G ENERAL INFORMATION AND PREVIOUS WORK .....................................8 Part 1. Regional stratigraphy. tectonics. and paiaeoenvironment ..................8 Regional stratigraphy and histoncal pempective .......................... ............ 8 Peace River region and northeastern British Columbia ...........................8 Southem and central Foothills. Alberta ................................................. 10 Peace River and Alberta Interior Plains subsurface ................................ 11 Tectonic Framework .......................................................................................