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In 1981, an Alberta Government project upgraded the monitoring of South Peak, Turtle Mountain, on the south margin of the 1903 Frank Slide. The monitoring program aimed at understanding the rates of deformation over large, deep fractures encompassing South Peak and predicting a second large rock avalanche on the mountain. The monitoring program consisted of a complement of static ground points and remotely monitored targets measured periodically, and climatic, microseismic, and deformation data collected automatically on daily intervals and archived. In the late 1980s, developmental funding for the monitoring program ceased and some of the installations fell into disrepair. Between May 2004 and September 2006, readings from the remaining functional monitoring points were compiled and interpreted. In addition, readings compiled previously were re-interpreted based on a more recent understanding of short-term movement patterns and climatic influences. These observations were compared with recent observations from an airborne light detection and ranging (LIDAR) digital elevation model and field photographs to give more precise estimates of the overall rates, extent, and patterns of motion for the past 25 years. Key words: Turtle Mountain, geological structure, light detection and ranging (LIDAR), monitoring, digital elevation model (DEM). En 1981, le gouvernement de l'Alberta a ameliore la surveillance de la pointe sud << South Peak >> de la montagne Turtle, sur la frontiere sud du glissement Frank de 1903. Le programme de surveillance vise a comprendre les taux de deformation des fissures larges et profondes sur << South Peak >>, et a predire une seconde avalanche rocheuse sur la montagne. Le programme de surveillance consiste a installer un complement de points statiques et de stations suivies a distance, qui sont mesures periodiquement. Des donnees climatiques, microsismiques et de deformation sont recueillies automatiquement a intervalles journaliers, et sont archivees. A la fm des annees 1980, le financement pour le developpement du programme de surveillance a cesse et quelques installations se sont deteriorees. Entre mai 2004 et septembre 2006, des lectures sur les points de surveillance encore fonctionnels ont ete compilees et interpretees. De plus, les lectures prelevees auparavant ont ete reinterpretees a partir des connaissances recentes sur les modeles de mouvement a court terme et les influences climatiques. Ces observations ont ete comparees a des recentes observations aeriennes d'un modele digital d'elevation, provenant de << light detection and ranging (LIDAR) >>, et des photos de terrain, afin d'estimer plus precisement les taux, l'etendue et la distribution des mouvements pour les derniers 25 ans. Mots-cles : Montagne Turtle, structure geologique, << light detection and ranging (LIDAR) >>, surveillance, modele d'elevation numerique << DEM >>. [Traduit par la Redaction], Introduction At 0410 on 29 April 1903, 30 x [10.sup.6] [m.sup.3] of limestone on the east face of Turtle Mountain (Fig. 1) moved rapidly into the Crowsnest Pass below. Over [...]

Abstract: The Frank Slide occurred on the east limb of the Turtle Mountain Anticline, which was thrust up along the folded and splayed Turtle Mountain Fault. Easterly dipping, Paleozoic limestones [...]