The Pioneer Mountains of Idaho expose a lower plate core of Precambrian and Ordovician metasedimentary rocks, which are intruded by Cretaceous and Eocene plutonic bodies. The core is separated by a detachment fault from a surrounding upper plate of Paleozoic and Tertiary sedimentary and volcanic units. The detachment system developed during a Tertiary extensional event which overprinted Paleozoic and Mesozoic east-directed compressional features, and exhibits both brittle and ductile (mylonitic) deformation. Stretching lineations in the mylonite and striations along the detachment surface both cluster around N65W. Composite planar fabrics (s- and c-surfaces) in the mylonite and limited development of a mylonitic front along the NW side of the core both suggest a top-to-the-west sense of shear. Minimum translation is estimated at about 17 km. The Pioneer structural complex is one of a number of metamorphic core complexes present along the North American Cordillera. All exhibit Tertiary extensional deformation, expressed as detachment faults structurally adjacent to ductile mylonitic shear zones. Extension directions, as indicated by stretching lineations within mylonite and striations along detachment faults, fall into regional groups in which the directions are similar in trend throughout each group. Asymmetric fabrics on both small and large scales give senses of shear and indicate that tectonic vergence within each group is directed outward from a central axis. The regional consistency of extension directions implies a regional control of extension in metamorphic core complexes. Much of central Idaho, and possibly a large part of eastern Idaho as well, may be riding on the upper part of an extensive detachment terrane, of which the Pioneer complex exposes the deeper levels. The Pioneer complex, and other core complexes, owes its present elevation to isostatic uplift over an overthickened crustal welt of local scale. Larger-scale uplift may be due to a similar isostatic adjustment over a broad zone of crustal thickening from Mesozoic compressional tectonics and intrusion.

No description available.

No description available.

No description available.

No description available.

This presentation was prepared and given during a meeting in 2004 between the United States Forest Service, Southern Paiute tribal members, and the BARA research team. The power point presents the summary of key findings from the report entitled Puha Flows from It: The Spring Mountains Cultural Landscape Study.

Mountain Views for Chamber Orchestra is a three-movement piece that evokes various geographic and aesthetic attributes of the Catalina Mountains in Tucson Arizona. It makes use of musical elements such as time, theme, color/timbre, and texture from the chamber ensemble that are conducive to the evocation of contours, colors, and polyphonies necessary for the images found in the work. "Early Morning Clouds Descending on the Catalinas," the first movement of Mountain Views depicts the picturesque Catalinas as they are often seen in the mild winter mornings of Tucson. The slow introduction conveys the early dawn and the episodic middle section uses ostinato-like repetitions and sudden juxtapositions of block-like figures that depict a hidden and secretive landscape. "Cancion del saguaro," the second movement is much slower than the previous movement and features a more aria-like treatment yet, still with some repetitious accompanimental figures. This movement depicts a lonely cactus within the mountain landscape with chromatic glissandos that imply scale and incline. "Danzas de sombra," the last movement depicts the mountain face at dusk using white-note collections and contrasting black-note collections that depict bright and shadowy sections of the mountain. This movement is more segmented or episodic with the different sections distinguishable not only by their key areas and modes but also registrally and metrically with a greater use of mixed meter and dance-like rhythms in the black-note shadowy sections.

No description available.

No description available.

No description available.