Date of Award
1991
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Abstract
The Upper Cretaceous Cardium Formation developed along the western margin of the Western Interior Seaway. The cyclic sedimentation style represented in the formation (consisting of a hierarchial array of shallowing upward cycles capped by transgression surfaces) developed in response to regressions and transgressions occurring on differing temporal scales. Shoreline progradation was generally to the northeast. The two main packages probably developed in response to eustatic third order sea level falls in the mid-Turonian and lower Coniacian. Superimposed on those cycles were fourth order relative sea level fluctuations (each cycle of about 10{dollar}\sp5{dollar} years duration) which were responsible for the development of individual allomembers in the Cardium Formation. Possible evidence for higher (fifth) order cyclicity is represented by few-meter thick sandier upward successions in offshore deposits, and punctuated shoreline progradation of the Kakwa Member.;The Kakwa Member represents the preserved shoreface portions of the lowest 3 progradational packages. It consists essentially of two stacked sandstone bodies, with the contact between the lower and upper portions being originally a near-horizontal (ravinement) surface developed during the E3 transgression. The sandstones above and below this surface can be distinguished on the basis of sedimentary structures, grain size and diagenetic history.;Conglomerates are locally present in the Kakwa Member, generally representing shoreface or beach deposits. A well-exposed section near Bay Tree (Alberta) suggests that wave-reworked gravels from shorefaces dominated by longshore transport are likely to be clast-supported, horizontally stratified and generally massive in appearance. Comparison of this section with other conglomeratic sections in the formation suggests that (in agreement with previous workers) bed lenticularity increases and clast segregation decreases in sections as the influence of fluvial depositional processes becomes greater.;This study suggests that basement tectonic elements had a greater influence on the pattern of deposition and erosion during Cardium time than previously recognised, controlling the position of bevels on the E5 and E7 surfaces, and the position of the basinward edge of the Kakwa Member. There is some evidence that structural elements may also have been important elsewhere in the basin at this time.
Recommended Citation
Hart, Bruce Samuel, "The Stratigraphy And Sedimentology Of The Upper Cretaceous Cardium Formation In Northwestern Alberta And Adjacent British Columbia (volumes I And Ii)" (1991). Digitized Theses. 1957.
https://ir.lib.uwo.ca/digitizedtheses/1957