Big Jim Mountain Lakes
Geography
The Big Jim Mountain Lakes are located on the northern skirt of Big Jim Mountain, consisting of rocky soils of intrusive rock geology. The exposed rock tends to be quartz-dolerite and granodiorite with influence from the intrusions originated from the Mount Stuart Batholith which underlies the Stuart Range and the nearby Wenatchee Mountains. This batholith is about 13 by 16 miles in extent. Two plutonic masses are separated by a thin screen of Chiwaukum Schist and rocks of the Ingalls Complex. The more-eastern pluton is 93 million years old, while the more-western rock mass is between 83 and 86 million years old.
The trail to the lakes consists of sandy loam the first half and boulders added in the second half of the trajectory. The west hills of Big Jim Mountain surrounding Lake Augusta grow tonalite and granodiorite corona-bearing dikes. The East hill grew pyroxenites, gabbro amphibolites and other diorites. Mineral boundaries are sharp along Big Jim Mountain except between these two matrix subdomains, which are not immediately distinguishable.
See also
References
- ^ Northwest Fishing Guide. 1952. p. 130.
- ^ *U.S. Geological Survey Geographic Names Information System: Big Jim Mountain Lakes
- ^ "Big Jim Mountain". SummitPost.com. Retrieved 12 Apr 2021.
- ^ Kelemen, P. B., & Ghiorso, M. S. (1986). Assimilation of peridotite in zoned calc-alkaline plutonic complexes: evidence from the Big Jim complex, Washington Cascades Contributions to Mineralogy and Petrology, 94(1), 12-28.
- ^ Beckey, Fred (2003). Cascade Alpine Guide: Climbing and High Routes - 1: Columbia River to Stevens Pass. Seattle, WA, USA: The Mountaineers Books. p. 236. ISBN 978-0-89886-577-6.
- ^ Evans, B. W., & Berti, J. W. (1986). Revised metamorphic history for the Chiwaukum Schist, North Cascades, Washington. Geology, 14(8), 695-698.