The pages of history are dotted with the names of men who have made only a small contribution to the sum of human knowledge. Often only a name, linked with a brief mention of some achievement, are all that remain to remind us that a man did exist. This thesis is an attempt to save one such man from near-obscurity. Much of Captain John Palliser has already been forgotten - his early life, his background, his character, are at least veiled if not completely obscured. All that remains is the record of his achievement; the report of the surveying expedition which, between 1857 and 1860, he led across the plains and mountains of what is now western Canada. Many historians and agriculturalists have consulted this report, but in my opinion only a few demonstrate more than a superficial knowledge of the document, and most have misinterpreted the conclusions there set down. This thesis is an attempt to reassess the Palliser survey. The report prepared by Captain John Palliser is well-written, very detailed, and comprehensive; in short, a perfect hunting ground for the research student. On the surface the study of this report is an integral unit falling within easily definable limits, but in reality, a complete reappraisal of its contents would require the combined skills of scholars in many fields, from anthropology through to astronomy. The problems of the scientist have been largely dropped in this study; a criticism of the geological, botanical, meteorological, and other similar observations has been left to the specialists in those particluar fields. Except where it has been necessary to draw upon the knowledge of the agronomist or economist, this thesis is an attempt to study the Palliser survey from the point of view of the historian. It has already been noted that the Palliser surveying expedition was in the field from 1857 to 1860. Between 1860 and the opening decades of the twentieth century, many other surveying parties traversed the plains and mountains of western Canada. This thesis is not an attempt to compare the Palliser survey with surveys conducted in the late nineteenth and early twentieth centuries, it is an attempt to evaluate Palliser's observations in the light of present-day knowledge. Finally, I would like to thank the members of the Faculty without whose assistance this thesis would not have been completed. The advice of Dr. M.Y. Williams and Dr. J.L., Robinson of the Department of Geology and Geography was invaluable in the preparation of the final chapter. Nevertheless, the opinions expressed in this thesis are my own. / Arts, Faculty of / History, Department of / Graduate

Two gigantic landslides in carbonate sequences were studied through a combination of remotely sensed datasets and detailed field investigation. Field investigations supplemented the remote analysis at both sites. The work presents the first detailed documentation of the Seymareh (Saidmarreh) landslide, Zagros Mountains, Iran, which is shown to be the largest known rock avalanche in the world and the largest known landslide of any type on the Earth’s land surface. Volume of the Seymareh rock avalanche (38 Gm³) was previously underestimated by nearly 50 percent. The failure mode was complex planar sliding involving fold-related bedding-parallel shears and local break-through of bedding. The overall dip of the sliding surface was 11°. Lateral release and toe release were provided by tectonically-weakened joints and by break-out likely assisted by fluvial undercutting, respectively. Broad scar morphology and outcrop-scale features indicate the presence of nine discrete sliding surfaces distributed through the failed sequence and define nine stacked plates involved in the detachment. The Valley of the Rocks rock avalanche (1.3 Gm³), Rocky Mountains, Canada is described in detail for the first time and shown to be the largest known rock avalanche in North America as well as the largest known landslide of any type in Canada. The failure mode was simple planar sliding along a bedding-parallel, slightly concave-up surface possibly coinciding with a thrust fault (average dip 25°). Lateral release and toe release were provided by bedding-normal joints and by glacial undercutting, respectively. There is a surprisingly high degree of similarity between the two rock avalanches, despite differences in tectonic and climatic setting.. Similarities and differences between the two gigantic landslides suggest several factors important in volume determination of gigantic landslides in carbonate sequences: 1) extensive contiguous source slope; 2) high degree of structural continuity, especially across slope parallel to strike; 3) a comparatively low failure surface dip; 4) discontinuity-parallel slopes, and subsequent toe undercutting; and 5) hard-over-soft geomechanical contrasts. Comparison with magnitude-mobility relationships for landslides over five orders of magnitude shows that the Seymareh rock avalanche suggests an upper limit for landslide mobility (fahrböschung = ~4°) on the Earth’s continental surface.

Two gigantic landslides in carbonate sequences were studied through a combination of remotely sensed datasets and detailed field investigation. Field investigations supplemented the remote analysis at both sites. The work presents the first detailed documentation of the Seymareh (Saidmarreh) landslide, Zagros Mountains, Iran, which is shown to be the largest known rock avalanche in the world and the largest known landslide of any type on the Earth’s land surface. Volume of the Seymareh rock avalanche (38 Gm³) was previously underestimated by nearly 50 percent. The failure mode was complex planar sliding involving fold-related bedding-parallel shears and local break-through of bedding. The overall dip of the sliding surface was 11°. Lateral release and toe release were provided by tectonically-weakened joints and by break-out likely assisted by fluvial undercutting, respectively. Broad scar morphology and outcrop-scale features indicate the presence of nine discrete sliding surfaces distributed through the failed sequence and define nine stacked plates involved in the detachment. The Valley of the Rocks rock avalanche (1.3 Gm³), Rocky Mountains, Canada is described in detail for the first time and shown to be the largest known rock avalanche in North America as well as the largest known landslide of any type in Canada. The failure mode was simple planar sliding along a bedding-parallel, slightly concave-up surface possibly coinciding with a thrust fault (average dip 25°). Lateral release and toe release were provided by bedding-normal joints and by glacial undercutting, respectively. There is a surprisingly high degree of similarity between the two rock avalanches, despite differences in tectonic and climatic setting.. Similarities and differences between the two gigantic landslides suggest several factors important in volume determination of gigantic landslides in carbonate sequences: 1) extensive contiguous source slope; 2) high degree of structural continuity, especially across slope parallel to strike; 3) a comparatively low failure surface dip; 4) discontinuity-parallel slopes, and subsequent toe undercutting; and 5) hard-over-soft geomechanical contrasts. Comparison with magnitude-mobility relationships for landslides over five orders of magnitude shows that the Seymareh rock avalanche suggests an upper limit for landslide mobility (fahrböschung = ~4°) on the Earth’s continental surface.