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Never Summer Mountains
The Never Summer Mountains are a mountain range in the Rocky Mountains in north central Colorado in the United States consisting of seventeen named peaks. The range is located along the northwest border of Rocky Mountain National Park, forming the continental divide between the headwaters of the Colorado River in Rocky Mountain National Park to the local-east and the upper basin of the North Platte River (North Park) to the local-west; the continental divide makes a loop in these mountains. The range is small and tall, covering only with a north-south length of while rising to over at over ten distinct peaks. The range straddles the Jackson-Grand county line for most of its length, and stretches into Jackson and Larimer county at its northern end. A panoramic view of the range is available from sections of Trail Ridge Road in Rocky Mountain National Park. One of the northernmost peaks, Nokhu Crags, is prominently visible from the west side of Cameron Pass.
==Geology==
The rocks of Never Summer Mountains are younger than most of the surrounding mountain ranges. They, along with the Rabbit Ears Range to the west, were formed by volcanic and intrusive processes 24-29 million years ago〔(USGS, America's Volcanic Past, Rocky Mountains )〕 and consist mostly of igneous granitic formations along with preceding metamorphic formations. Most of the highest peaks in the range are granodiorite that was uplifted during the Miocene epoch. The range's highest summit, Mount Richthofen, is the remnant of an andesite volcanic plug. The Nokhu Crags in the north are mostly Pierre Shale dating from Cretaceous times. A large thrust fault underneath the Kawuneeche Valley thrust older Precambrian rocks on top of the younger Cretaceous rocks on the east side of the range. The southern peaks are Miocene-aged granite, and finally Precambrian-aged biotite gneiss and schist.〔Geologic map of the Mount Richthofen quadrangle and the western part of the Fall River Pass quadrangle, Grand and Jackson Counties, Colorado, J.M. O'Neill, U.S. Geological Survey, 1981. http://ngmdb.usgs.gov/Prodesc/proddesc_9119.htm〕〔(USGS, North Park-Medicine Bow Mountains Project: Task 3: Neogene landscape evolution )〕
Beginning two-million years ago glaciers began carving the jagged peaks of the Never Summer Mountains. Successive waves of glaciation continued to reshape the mountains until the Pinedale Glaciation ended twelve-thousand years ago.〔Harris, Ann G., Esther Tuttle and Sherwood D. Tuttle, ''Geology of National Parks,'' Kendall/Hunt Publishing Company, 6th ed., 2003, ISBN 978-0-7872-9970-5〕
The peaks are enormous weathered masses of granitic rock heavily covered with green and orange lichens surrounded on all sides by large fields of talus shed from the original peaks. Many alpine lakes are nestled amongst the peaks. Most vegetation is low-growing and stunted. Few trees grow at the higher altitudes and Krummholz abounds.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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