PALISADE GLACIER of the Hign SIERRA of CALIFORNIA1
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BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA VOL. 44, t=P. 575-600, II FIGS. JUNE 30, 1933 PALISADE GLACIER OF THE HIGn SIERRA OF CALIFORNIA1 BY 0. D. TON ENGELN (Presented before the Geological Society, December 27, 1929) CONTENTS Page Introduction.................................................................................................................. 575 Palisade Glacier............................................................................................................ 576 Location ............................................................................................................... 576 Size, altitude, former extension.......................................................................... 579 Movement and crevasses.................................................................................... 581 Moraines and glacier tables.......................................................... .................... 583 Glacial chutes........................................................................................................ 585 Glacial pavement.................................................................................................. 589 Glacier stairway and pater noster lakes.................................................................... 590 Introduction.......................................................................................................... 590 The cirque............................................................................................................. 592 Retreat of the cross-wall...................................................................................... 594 Origin of the cross-wall........................................................................................ 595 Basins and steps below the cross-wall............................................................... 597 >% __ I ntroduction Between Walker Pass, latitude 35° 40' north, altitude 5248 feet, and Tioga Pass, latitude 37° 35' north, altitude 9941 feet, a distance of 158 miles on a north and south lirLe, there are no highways across the high, eastern front of the Sierra Nevada Mountains of California. This great barrier to travel on east and west lines is commonly referred to as the High Sierra. The greatest elevation on its crest line is Mount Whitney, 14,496 feet, the highest summit in the United States. From Mount Whit ney, at latitude 36° 35' north, the elevation of the. crest line declines southward rather regularly in 65 miles, on a north and south line, to the elevation of Walker Pass. North of Mount Whitney there is, however, only little change in elevation of the h;gher points in the 93 miles to Tioga Pass. Thus, Mount Sill, latitude 37° 6' north, has an elevation of 14,254 feet, and Mount Lyell, latitude 37° 44' north, 13,090 feet. These peaks, 1 Manuscript received by the Secretary of the Society, January 26, 1932. Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/3/575/3430356/BUL44_3-0575.pdf by guest on 26 September 2021 576 O. D. VON ENGELN---PALISADE GLACIER and the many others along the crest line, are held to be monadnocks rising above an old erosion surface, the Subsummit Plateau, that constitutes the upland level of the western slope of the Sierra Nevada. As the aver age altitude between peaks of the Subsummit Plateau is 11,500 feet, the scarp of the High Sierra from Mount Whitney northward presents an imposing wall (figure 1) towering 8000 feet above the floor of the Owens Yalley at its base. In this section, below Mount Sill, is Palisade Glacier, the southernmost glacier in the United States (figure 2). F ig u r e 1 .—Section of the Crest Line and dissected Scarp of the High Sierra half way between Split Mountain and Mount Sill Telephoto view across the summit of the Inyo Range. Viewpoint is 30 miles distant from the Sierra summits. Photo by Carl Allen. P a l is a d e G l a c ie r LOCATION There are several references in geographic and geologic literature to the effect that the southernmost glacier of the High Sierra “is a few miles north of Mount Whitney” 2 and “the small glacier in latitude 36° 35' near Mount Whitney now seems to be the (glacier in the United States) 2 N. M. Fenneman : Thysiography of Western United States. New York, 1931, p. 41C». Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/3/575/3430356/BUL44_3-0575.pdf by guest on 26 September 2021 io ,11 III 0 M' W'vux^n-' VU*.* vC + .\A lic e PALISADE PALISADE GLACIER F i g u r e 2 .— Sketch Map of the Region of the Palisade Glacier, California Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/3/575/3430356/BUL44_3-0575.pdf by guest on 26 September 2021 578 0 . D. VOW ENGBLJST----PALISADE GLACIER farthest south.” 3 The glacier is reported to exist at the head of a cirque of East Pork. The cirques of East Pork are west of the crest line of the Sierra Nevada scarp but open directly to the north, hence are under the shadow of Mount Russell and Mount Young. Further, they are pro tected from the east and the west sun by high and steep ridges extending north; these ridges are the sides of the cirque amphitheatre. The site, accordingly, is extremely favorable for preservation of a glacier. How ever, the area available there that is above the level of 12,500 feet would only suffice for a minute cliff gacier. The glacier is supposed to be under the shadow of Russell which is only 14,190 feet high. Hence, the presence of a glacier in those parts can not be ascribed to the superior height of Mount Whitney. If this one does not exist, no glacier is present west of the scarp line for the distance of a degree of latitude farther north, and there the small Darwin Glacier, the terminus of which is at an alti tude of 12,500 feet, occupies the head of a cirque that also faces directly north. Lawson 4 evidently saw the cirque at the head of the south branch of East Fork but makes no mention of an existing glacier. He makes note, however, (op. cit., p. 366) that according to J. N. Le Conte “glaciers still linger in the cirques of the summit divide but a short distance north of the head of the Kern.” The Mount Whitney, California, quadrangle topographic sheet of the United States Geological Survey, 1919 edition, shows neither a glacier nor even a snowbank at sites around latitude 36° 35' north. John M uir5 asserts he “made excursions over all the High Sierra” in search of glaciers (page 24) and that he found 65 existing residual glaciers “in that portion of the range lying between latitude 36° 30' and 39°” (page 20); but Mount Whitney . does not now cherish a single glacier. Small patches of lasting snow and ice occur on its north ern slopes, but they are shallow, and present no well marked evidence of glacial motion (page 35). If Muir had said that the existing glaciers of the High Sierra are found north of 37° instead of 36° 30' he would have been precisely accurate. At 37° 4', in the upper levels of the large cirque at the head of the South Fork of Big Pine Creek, there are mapped seven distinct glacierets, the largest of which is about half a mile in each 3 A. Knopf: A geologic reconnaissance of the Inyo Range and the eastern slope of the southern Sierra Nevada, California. U. S. Geol. Survey, Prof. Pap. 110, 1918, p. 105. (Knopf’s source for the statement above is a paper by R. E. Dickerson : Whitney Creek, its glaciation and present form, California Phys. Geogr. Club Bull., vol. 2, 1908, pp. 14 to 21.) 4 A. C. Lawson: Geomorphogeny of the upper Kern Basin. Univ. California Publica tions, Bull. Dept. Geol., vol. 3, 1903, p. 353. s John Muir : Mountains of California. New York, 1894, 1911, p. 34. Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/44/3/575/3430356/BUL44_3-0575.pdf by guest on 26 September 2021 PALISADE GLACIER 579 dimension. These ice masses were seen only from a distance by the author. They are small and possibly do not exhibit the characteristic of a true glacier—motion within the mass. The cirque basin at the head of the South Fork of Big Pine Creek in which these snow patches persist opens to the nortJ¥*and northeast. The mountain wall, “Middle Palisade,” elevation 14,049 feet, under which five of the glacierets occur, has a west to east trend. It is this northern exposure with consequent “broad frosty shadows” (Muir) that determines this most southerly site of lingering glaciation. The same conditions, accentuated, three miles farther north at the head of the north branch of Big Pine Creek (figure 2) and under the shadow of three peaks approaching Mount Whitney in elevation (Mount Sill, 14,254 feet; Mount Winchell, 13,749 feet; and Agassiz Needle, 13,882 feet) have fixed the site of Palisade Glacier, the most southerly glacier in the United States, and have enabled it to maintain itself in dimensions greater than those of rival glaciers situated farther north. SIZE, ALTITUDE, FORMER EXTENSION Palisade Glacier, as mapped by the United States Geological Survey in 1909, is more than one and one-half miles long in its greater dimen sion—that is, parallel to the “palisade” mountain wall at its head. From the mountain wall forward to the moraine at the widest part is nearly three-quarters of a mile. The Mount Lyell Glacier, on the northern slope of Mount Lyell, latitude 37° 45' north, is stated by Russell6 to be the most extensive existing glacier in the High Sierra and to be “less than a mile in length with a somewhat greater breadth.” The Mount Lyell Glacier is thus