Upper Devonlan sponge-algal mud mounds, southern flank of Miette reef complex, Jasper National Park, Alberta, Canada Masahiro Shiraki Department of Earth and Planetary Sciences McGill University Montreal, Canada August, 1996 A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfilment of the requirements for the degree of Master of Science O Masahiro Shiraki 1996 a l+lNa tional Libraty Bibliothb ue nationale ,,nada du Cana a Acquisitions and Acquisitions et Bibliographie Services services bibliographiques 395 Wellington Street 395, rue Wellington Ottawa ON K1A ON4 Oltawa ON K1A ON4 Canada Canada The author has granted a non- L'auteur a accordé une licence non exclusive licence dowing the exclusive permettant à la National Library of Canada to Biblioîheque nationale du Canada de reproduce, loan, disûibute or sel1 reproduire, prêter, distribuer ou copies of this thesis in microfom, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/fih, de 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 protége cette thèse. thesis nor substantial extracts fiom it Ni la Wse 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. ABSTRACT A senes of small mud mounds are exposed in the McConnell and Miette thrust sheets on the southern flank of the Miette reef complex. They occur on the southeastward inclined carbonate clinoforms of the late Frasnian Arcs Member. These mounds are rooted on marine, argillaceous lime mudstones and are surrounded by lime mudstones of several prograding clinoforms of the upper Arcs Member or dolomitic siltstones of the lower Ronde Member. Mounds are approximately 17 to 36 m high and 32 to 81 m wide and columnar to domal in shape. The lower part of the mounds consists of sponge- rich wackestones and packstones, and locally larninar strornatoporoid boundstones. Calcareous green algae tend to predominate in the upper parts of the mounds. Variable cavities occur and are filled with geopetal sedirnents, isopachous fibrous and blocky calcite cements. The most common cavity types, irregular and irregular stmmatactoidal cavities, might be related to organic origins, possibly the decay of sponges in conjunction with submarine cementation. Abrupt mound margins indicate that the mounds grew upwards more rapidly than the accumulation of the adjacent basin and clinoforming dope sediments. Vertical constrictions and shape changes suggest that the mounds developed in two or more distinct stages that tracked sea level rises. The sediments in much of the laterally equivalent Arcs Member bank above the Miette reef complex proper a few kilometers to the north were deposited in very shallow water 1 to 2 m). This together with the geometry of (C the gently basin sloping carbonate clinoforms suggests that the water depths of mound initiation was 20 to 30 m. or the thickness of the mounds. ii Initiation of the mounds took place in moderately agitated water with the deposition of sponge-rich wackestones. Later mound growth took place in more agitated conditions in which calcareous algal packstones were deposited. The depositional environment of the Miette mud mounds was similar to the Ancient Wall and subsurface Meekwap wackestone/mudstone bioherms with respect to shallow water depths and water agitation. Laminar stromatoporoids, calcareous algae especially renalcids, and the massive colonial rugose coral Phillipsastrea are widely distributed in the Ancient Wall bioherrns, but contain no obvious sponge material and have rare stromatactoidal cavities. The differences in the biota between these two localities could be due to diffennces in slope configuration and amounts . of basin sediments being deposited. Sponge-rich wackestones of the "r6cifs rouges'' (Facies A), of the Upper Devonian rnud mounds in Belgium are similar to the Miette mud mounds. However, the Belgium mounds are interpreted to have been deposited in much deeper water below storm wave base. The Miette mud mounds show that this facies is not depth dependent and can be deposited in very shallow water. Une serie de petits monticules boueux sont exposes le long des couches de chevauchement McConnell et Miette sur le flanc sud du cornplex r6cifal Miette. Ils se trouvent sur les dBp8ts de pente inclinaison sud-est appartenant au Membre des Arcs avec un Bge Frasnien tardif. Ces monticules sont enracines sur des mudstones argileuses calcaires d'origine marine et sont entoures par des mudstones calcaires du Membre des Arcs compos6es de plusieurs d6p6ts de pente progradants ou de siltstones dolomitiques du Membre inferbure de la Ronde. Les monticules sont approximativement de 17 B 36 m de hauteur et de 32 à 81 m de iargeure et ont une forme colunaire domale. La partie inférieure des monticules consiste à des wackestones et des packstones riches en Bponges, avec localement des boundstones & stromatoporoides. Les algues a vertes calcaires tendent predominer dans les parties sup6rieures des monticules. Des cavitds variables sont présentes et sont obstru6es de sedirnents a geop6tales et de ciments calcitiques isopaques forme fibreuse en partie radiaxiale et d'autres à forme bloquaire. Les types de cavit6 les plus commun, cavitees irréguEBres et d'autres stromatocoidales irr6gulières, peut être liees à des organismes B corps moux, possiblement la d6compositon d'éponges en conjonction avec une cimentation manne. Les marges abruptes des monticules indiquent que leur croissance vers le haut a Bt6 plus rapide par rapport & l'accumulation du bassin adjacent et des sediments de pente. Les resserements verticaux et les changements de forme sugghrent que les monticules se sont d6velopp6s en deux ou plusieurs Btapes distinctes ayant trac6 les remontdes du niveau matin. Par dessus du complexe principal rdcifale Miette se touvant quelques kilomhtres vers le nord, la majorit6 des sbdiments de l'équivalent laterale de la rive du Membre des Arcs ont 6t6 d&posds dans des eaux peu profondes (e 1 & 2 m). Ceci avec la g6orn6trie des ddp&ts de pente carbonatds B faible pente basinale sugghrent que la profondeur de l'eau correspondant h l'initiation des monticules &ait de 20 & 30 m, ou I'epaisseur des monticules. L'initiation des monticules a pris place dans une eau mod6r4ment agitee avec le ddp6t de wackestones riches en Bponges. La subsBquente croissance des monticules a pris place dans des conditions plus agitees permettant le d6p6t de packstones alguaires calcaires. L'environrnent de d6pbt des monticules boueux Miette &ait similaire a celui des biohermes Ancient Wall et ceux wackestones/mudstones de subsurface Meekwap de point de vue profondeur et agitation d'eau. Des stromatoporoides laminaires, algues calcaires particulihrement renalcides, et le corail massive colonial rugose Phillpsastrea sont largement distribues dans les bioherrnes Ancient Wall, mais contient aucun materiel spongiaire et possbde de rares cavites stromatactoidales. Les differences de biota entre ces localit4s peut probablement être dues aux diffhnces dans la configuration de pente et les quantites de shdiments de basin en voie de dBp6t. En BBlgique, les récifs Rouges wackestones riches en Bponges (Facies A) appartenant aux monticules boueux du Devonien Sup6rieur sont similaires à ceux des monticules boueux Miette. Cependant, les monticules belges sont interprétes d'être d6pos6s dans une eau plus profonde en dessous de la base de vague de tempête. les monticules boueux Miette montrent que ce facies est independant de la profondeur et peut être d6pos6 dans une eau peu profonde. TABLE OF CONTENTS ABSTRACTnnnn.n..o.. ......................*.............................................................e................i ...... ............ mMMAIRE ......................................................................................... iii .......................................................................................... TABLE OF CONTENTS v ... LIST OF FIGURES ...................... ..................................................................... vii LlST OF TABLES. X ..m.m.mO...m.~m.. ~.m~mmn~.....nm..mm.na.....n.me.no~onmm.e...mn.nm*..n.nm~~....o.~~.~..m .......... .. LIST OF APPENDICES ......................................................................... xi ACKNOWLEDGEMENTS.. ..................................................................................... xii . ......... . ............................................................... CHAPTER 1 INTRODUCTION 1 ................. ..................... 1.1. Introduction ................................................... 1 .................................. ................................................. 1.2. Previous studies 2 . ............ .................... .................... 1. 3 Geological setting and stratigraphy 2 ................. .. ...... ........... .............................. 1.4. Field wotù and methods 4 . ........................................................ CHAPTER 2 NATURE OF MUD MOUNDS 18 ........ ................................ ............................................. 2.1.ûccutmnœ 18 l.. ... ........... 2.2. Sires and configuration ..................................................... 18 ......................................... 2.3. Substrate and basal pait of mud mounds ................. ..... ......................................................................... 2.4. liofacies ....... ................ .. 2.5. Biota ...................................................................... . . ................... ... .... ..................................................................... 2.6. CaWes ............... . ......................................... 2.7. Vertical Zonation .... ............ 2.8. Summaiy ......................................................................... CHAPTER 3. DEVELOPMENT OF MUD MOUNDS. ......................... ........ ... . . ................... . ....... 3.1 Depth and type of depositional environment .. .................... ................... 3.2. Role of organisms in accretion of mounds ... .................... ..................................................... 3.3. Early lithification . . ... .............. .............................................................. 3.4. Origin of cavrtiea 3.5. Geopetal sediment ................................................................................. ........................................................................... 3.6. Paragenetic sequenœ 3.7. Surnmary .................................................................................................. . ..... CHAPTER 4 COMPARISON WlTH OTHER DEVONIAN MUD MOUNDS 4.1. Ancient Wall reef complex ..................................................................... .. ....... 4.2. Meekwap Buildups. subsurface of Alberta Basin. ................ ............... . ..... .............. ................................... 4.3. Belgiurn mud mounck ....................... .. 4.4. Summaiy ...........ee..............................~...........~............ . ..................... . .................... CHAPTER 5 SUMMARY AND CONCLUSIONS ...................................................................... .... ............................. REFERENCES ..... ......................................................................... APPENDIX 1 ....................... APPENDIX 2 ........................................................................ .....m....m.m..mmmm~..~.. . . . .............................. .. ............. ..... . APPENDIX 3 vil LIST OF FIGURES Figure 1. Reef map of the Middle and Upper Devonian from the Noithwest ........ ..................... .. . ... .......... Territories to southem Alberta 6 Figure 2. Location of Miette reef complex and Ancient Wall reef complex, ............................ ...... ........................................ Jasper National Pak 7 Figure 3. Location of five rnud mounds, Miette and McConnellIhmst sheets, ................. . ........... ............... . ............... . Jasper National Park 8 Figure 4.A. Schematic geological cross section of the Miette buiidup and strata flanking the southeastem margin of the reef complex.. 9 Figure 4.8. Schematic cross section showing position of mounds on southeast sloping clinoforms in upper Arcs equivalent strata. .. .. . . 9 Figure 5. Mud mounds 1 (right) and 2 (Mt), McConnell thrust sheet, .................................. ................................... head of Poachers Creek 10 - ............................. ............. ................... Figure 6. Mud mounds studied 1 5 11 Figure 7. Stratigraphy of rnud mounds 1 and 2 in McConnell thrust ................ shûût, Poachers Creek .....me~m..m..mm.~.............~.........1.m2 ....m........... Figure 8. Configuration and sample kcalities of rnud mounds 1 and 2, .. .... . .. .. .... . ... .... head of Poachers Creek, McConnell Thrust sh eet. 13 Figure 9. Configuration and sample bcalities of rnud mounds 3, 4 and 5, ................. .................................... . .................... Miette Thrust sheet 14 Figure 10. "Eustatic" sea level curve for the Devonian succession of the .................. ....... .................... southern Canadian Rocky Mountains 15 Figure 11 . Schematic stratigraphic column, head of Poachers Creek, ........................ ... ..... . ... . ............. .... ....... McConnell thrust sheet 16 Figure 12 . Schematic stratigraphic column, head of Fiddle River, Miette ....................... .. ............................... . . . . thrust sheet 17 Figure 13. Mount Hawk argillaceous carbonates directly beneath ........................... rnud mounds and the basal part of rnud mound 5 33 .................... Figure 14. Occurrence of skeletal components in rnud mound 1 34 Figure 15. Occurrence of skeletal components in rnud mound 2 thmugh 5. ................. ... ........ ... ............................. . . . ......... 35 Figure 16. Photomicrographs showing skeletal elements in .................................................... wackestones and lime mudstones . .. Figure 17 Photomicrographs showing wackestone and packstone facies . .................................................................................. Figure 18 Sponge anatomy . ............. Figure 19 Different types of megasclere siliceous sponge spicules . ................. . ....................... .. ................. Figure 20 An inferred sponge fossil . Figure 21 Tracing of Figure 20 showing the position of the thin .................. .. ................ section and infened outline of sponge wall . ............................................... Figure 22 Examples of caIcamus green algae . .. Figure 23 Calcareous green algae in wackestone facies of rnud mounds . .............................. Figure 24 Calcareous blue-green algae in mud mounds . ............... ... ... Figure 25 Fossils and skeletal components in mud mounds . .................... ..................... Figure 26 Types of Miette rnud mound cavities . Figure 27 lrmgular cavities filled with fibrous calcites in sponge ................... ... spicule-rich wackestone and lime mudstone facies . ............................ Figure 28 lf regu lar cavities and stromatadoidal cavities . ................... Figure 29 Distribution of biofacies within mud rnounds 1 and 2 . ................... .... Figure 30 Distribution of biofacies within mud mounds 3 to 5 . .............. .. .................................................. Figure 31 lnferred sponge fossils . . . ..................................................................................... Figure 32 Shelter cawt~es . Figure 33 Photomicrograph of shelter cavities from part of outcrop . ..................... .. ................................................... shown in Fig 32k . Figure 34 Shelter cavities beneath laminar stromatoporoids. ................................................ rnud mound 1 (Tracing of Figuiie 33) . .................................................................... Figure 35 Examples of bioemsion . ........................ Figure 36 lrregular cavities infened to be the organic origin
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