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37-465: Little Yosemite Valley is a tread on the glacial stairway of the Merced River that runs from Yosemite Valley up to Mount Lyell, gaining some 7,600 ft (2,316 m) of vertical elevation over 21 mi (34 km) and is situated some 2,000 ft (610 m) in elevation above Yosemite Valley proper. The north wall of Little Yosemite has not been subject to the same kinds of glacial planing as

74-487: A water wheel over the glacially polished granite saddle between Sugar Loaf and Bunnell Point into a delightful pool at the eastern head of Little Yosemite Valley. This cascade is often mistaken for Bunnell Cascade which is located between the Lost Valley and Echo Valley at 37°44′43.87″N 119°28′14.95″W  /  37.7455194°N 119.4708194°W  / 37.7455194; -119.4708194 . Bunnell Point

111-409: A glacier or ice sheet. It may consist of partly rounded particles ranging in size from boulders (in which case it is often referred to as boulder clay) down to gravel and sand, in a groundmass of finely-divided clayey material sometimes called glacial flour . Lateral moraines are those formed at the side of the ice flow, and terminal moraines are those formed at the foot, marking the maximum advance of

148-417: A long moraine bank marking the ice margin. Several processes may combine to form and rework a single moraine, and most moraines record a continuum of processes. Reworking of moraines may lead to the formation of placer deposits of gold as is the case of southernmost Chile . Moraines can be classified either by origin, location with respect to a glacier or former glacier, or by shape. The first approach

185-517: A series they are referred to as a glacial stairway . Most riegels can be identified by having smooth faces on the up-valley sides, while the down-valley sides show signs of having been plucked (eroded by the removal of rocks and blocks from the bedrock). Lateral moraines A moraine is any accumulation of unconsolidated debris ( regolith and rock ), sometimes referred to as glacial till , that occurs in both currently and formerly glaciated regions, and that has been previously carried along by

222-428: A terminal moraine. They form perpendicular to the lateral moraines that they reside between and are composed of unconsolidated debris deposited by the glacier. They are created during temporary halts in a glacier's retreat. In permafrost areas an advancing glacier may push up thick layers of frozen sediments at its front. An arctic push moraine will then be formed. A medial moraine is a ridge of moraine that runs down

259-522: Is a granite dome summit in Mariposa County, California . Bunnell Point rises to 8,173 ft (2,491 m) AMSL. Bunnell Point is located at 37°44′19.73″N 119°28′2.57″W  /  37.7388139°N 119.4673806°W  / 37.7388139; -119.4673806 comprising the southeast margin of Little Yosemite Valley. Cascade Cliffs is a wall of unjointed granite that rises to 8,170 ft (2,490 m) AMSL, 1,930 ft (588 m) above

296-460: Is a little under 4 miles (6.5 km) from the trailhead in Yosemite Valley and about 3.5 miles (5.5 km) from the summit of Half Dome at 37°43′57.43″N 119°30′51.68″W  /  37.7326194°N 119.5143556°W  / 37.7326194; -119.5143556 . Fires are allowed in the two communal campfire rings just outside the campground. Potable (drinking) water is not available at

333-458: Is apparent in the image of Little Yosemite Valley from Washburn Point, above right . The west end and south wall of the canyon are "exceptionally massive, few cliffs anywhere in the Yosemite region exhibit a more complete absence of fractures." This also leads to an almost complete absence of vegetation as well, as there are few opportunities for roothold. The north wall in contrast, and similarly to

370-450: Is suitable for moraines associated with contemporary glaciers—but more difficult to apply to old moraines , which are defined by their particular morphology, since their origin is debated. Some moraine types are known only from ancient glaciers, while medial moraines of valley glaciers are poorly preserved and difficult to distinguish after the retreat or melting of the glacier. Lateral moraines are parallel ridges of debris deposited along

407-514: Is the granite more continuously massive than in the Cascade Cliffs. Only one horizontal master joint divides the rock (in the lower left) The scales on the cliffs are merely surficial features due to exfoliation. The dark streaks indicate the paths followed by the ribbon cascades which descend from the upland in the spring, when the snow is melting, and from which the cliffs take their name. There are two wide, relatively short yet quite deep arches at

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444-583: Is wrapped by a broad, striped granite apron with an approximately 40° slope that appears to rise some 500 ft (152 m) from the valley floor. Sugar Loaf Dome is a granite dome in Yosemite National Park at the northeastern head of Little Yosemite Valley at 37°44′27.47″N 119°28′44.94″W  /  37.7409639°N 119.4791500°W  / 37.7409639; -119.4791500 which rises to 7,697 ft (2,346 m) AMSL. Although Sugar Loaf Dome has been repeatedly subject to glaciation,

481-793: The Yosemite Valley floor at Tenaya Canyon and 2,686 ft (819 m) above the floor of Little Yosemite Valley. The trail to Half Dome branches to the north from the main Little Yosemite Valley trail near the ranger station, out houses and campground. Moraine Dome is a granite dome in Yosemite National Park along the northern margin of Little Yosemite Valley at 37°44′35.15″N 119°29′24.49″W  /  37.7430972°N 119.4901361°W  / 37.7430972; -119.4901361 which rises to an elevation of 8,036 ft (2,449 m) AMSL, 1,906 ft (581 m) above

518-417: The Merced River and make up the southern wall of Little Yosemite Valley at 37°43′27.73″N 119°29′13.56″W  /  37.7243694°N 119.4871000°W  / 37.7243694; -119.4871000 , 1.6 mi (3 km) southwest of Bunnell Point and 2.4 mi (4 km) northeast of Mount Starr King , of which Cascade Cliffs comprises the northern flank. In few other places in the Yosemite region

555-498: The Merced River. Moraine Dome is notable because the presence of lateral moraines from the Merced Glacier . It is likely that these moraines represent the highest level attained by glacial ice in Little Yosemite Valley. Although it is about as high as Sentinel Dome Moraine Dome is dwarfed to relative insignificance by its proximity to the bulk and elevation of Clouds Rest to the north. The south western margin of Moraine Dome

592-548: The base of Nevada Fall to a peak elevation of 7,076 ft (2,157 m). A smaller, mesa-like dome called Mount Broderick stands immediately adjacent to Liberty Cap. Together, they form a barrier on the north side of the mouth of Little Yosemite Valley. Both Liberty Cap and Mount Broderick are roches moutonnées , features that protruded above or resisting being overridden by successive Merced River glaciers because they are made of massive unjointed granite sufficiently resistant to glacial erosive power, leaving them prominent in

629-525: The base of the cascade and leaves the valley at 5,907 ft (1,800 m) for a total elevation difference of 278 ft (85 m) over a trail length of 3.25 mi (5 km). The trail is largely forested, with two notable areas of exposure, the first .1 mi (0 km) on the approach to the southwest buttress of Moraine Dome and the second, .25 mi (0 km) of burned forest, at approximately 2.3 mi (4 km) above Nevada Fall, across from Cascade Cliffs. The hike-in campground here

666-404: The bottom of the cliff. The Quarter Domes are granodiorite domes rising between Half Dome and Clouds Rest. They comprise two domes, West Quarter Dome and East Quarter Dome. The higher of the two is East Quarter Dome, at 8,318 feet (2,535 m); West Quarter Dome stands at 8,160 feet (2,490 m). The Merced River enters Little Yosemite Valley at 6,185 ft (1,885 m) at the pool at

703-514: The campground in which to store food, toiletries, and trash safe from abundant hungry black bears that frequent Little Yosemite. Glacial stairway A riegel (from German, literally crossbar ) is a transverse ridge of bedrock that has been exposed by glacial erosion . Riegels are also known as rock bars, thresholds, and verrous. They are found in glaciated valleys, and are often associated with waterfalls and zones of rapids when streams are present. When multiple riegels are stacked in

740-426: The campground. River water is available nearby, at the Merced River. The river is the only water source for the area. Little Yosemite Valley Ranger Station is staffed during summer. A composting toilet is available for use near the campground 37°44′0.45″N 119°30′55.99″W  /  37.7334583°N 119.5155528°W  / 37.7334583; -119.5155528 The Park Service provides communal food lockers at

777-594: The center of a valley floor. It forms when two glaciers meet and the debris on the edges of the adjacent valley sides join and are carried on top of the enlarged glacier. As the glacier melts or retreats, the debris is deposited and a ridge down the middle of the valley floor is created. The Kaskawulsh Glacier in the Kluane National Park , Yukon , has a ridge of medial moraine 1 km wide. Supraglacial moraines are created by debris accumulated on top of glacial ice. This debris can accumulate due to ice flow toward

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814-579: The core of this spur has resisted the icy onslaughts because what remains today is massive throughout except for one master joint, horizontal in character. Post-glaciation, Sugar Loaf Dome retains a 1,300 feet rise over, and its shoulder perturbs the course of the Merced River and provides the relief over which the river descends into Little Yosemite via Cascade Fall. Cascade Fall at 37°44′11.32″N 119°28′53.13″W  /  37.7364778°N 119.4814250°W  / 37.7364778; -119.4814250 , elevation 6,225 ft (1,897 m) AMSL tumbles via

851-511: The glacier has melted. Moraines may form through a number of processes, depending on the characteristics of sediment, the dynamics on the ice, and the location on the glacier in which the moraine is formed. Moraine forming processes may be loosely divided into passive and active . Passive processes involve the placing of chaotic supraglacial sediments onto the landscape with limited reworking, typically forming hummocky moraines. These moraines are composed of supraglacial sediments from

888-428: The glacier margin (up to 80 degrees) than further away (where slopes are typically 29 to 36 degrees. Ground moraines are till-covered areas with irregular topography and no ridges, often forming gently rolling hills or plains, with relief of less than 10 meters (33 ft). Ground moraine is accumulated at the base of the ice as lodgment till with a thin and discontinuous upper layer of supraglacial till deposited as

925-534: The glacier retreats. It typically is found in the areas between end moraines. Rogen moraines or ribbed moraines are a type of basal moraines that form a series of ribs perpendicular to the ice flow in an ice sheet . The depressions between the ribs are sometimes filled with water, making the Rogen moraines look like tigerstripes on aerial photographs . Rogen moraines are named after Lake Rogen in Härjedalen , Sweden ,

962-570: The glacier. Other types of moraine include ground moraines ( till -covered areas forming sheets on flat or irregular topography ) and medial moraines (moraines formed where two glaciers meet). The word moraine is borrowed from French moraine [mɔ.ʁɛn] , which in turn is derived from the Savoyard Italian morena ('mound of earth'). Morena in this case was derived from Provençal morre ('snout'), itself from Vulgar Latin * murrum ('rounded object'). The term

999-415: The ice surface. Active processes form or rework moraine sediment directly by the movement of ice, known as glaciotectonism. These form push moraines and thrust-block moraines, which are often composed of till and reworked proglacial sediment. Moraine may also form by the accumulation of sand and gravel deposits from glacial streams emanating from the ice margin. These fan deposits may coalesce to form

1036-503: The landform's type locality. Closely related to Rogen moraines, de Geer moraines are till ridges up to 5m high and 10–50m wide running perpendicular to the ice flow. They occur in large groups in low-lying areas. Named for Gerard De Geer , who first described them in 1889, these moraines may have developed from crevasses underneath the ice sheet. The Kvarken has a very high density of de Geer moraines. End moraines, or terminal moraines , are ridges of unconsolidated debris deposited at

1073-411: The moraine. There are two types of end moraines: terminal and recessional. Terminal moraines mark the maximum advance of the glacier. Recessional moraines are small ridges left as a glacier pauses during its retreat. After a glacier retreats, the end moraine may be destroyed by postglacial erosion. Recessional moraines are often observed as a series of transverse ridges running across a valley behind

1110-589: The north wall of Yosemite Valley, has been subject to much less glacial planing and is much more differentiated and vegetated. Liberty Cap is a granite dome in Yosemite National Park , California , United States, which lies at the extreme northwestern margin of Little Yosemite Valley. It lies adjacent, to the north of Nevada Fall , on the John Muir Trail at 37°43′43″N 119°31′57″W  /  37.72861°N 119.53250°W  / 37.72861; -119.53250 . It rises 1,700 feet (520 m) feet from

1147-435: The pass from the overflowing Tuolumne River basin. These rocks were thus subject to tremendous gravitational and flow forces yet retain a remarkable degree of integrity, eroding almost exclusively and superficially along exfoliation joints . The south wall of the valley has been subject to extensive glacial planing, with all jointed granite completely smoothed away, leaving a stark, featureless unjointed sheer cliff face, as

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1184-498: The post-glacial landscape. Both features are glacially polished on their glacier-facing side and ragged on their leeward side. Half Dome is a granite dome in Yosemite National Park located at the northwestern end of Little Yosemite Valley at 37°44′45.6″N 119°31′59.4″W  /  37.746000°N 119.533167°W  / 37.746000; -119.533167 — possibly Yosemite's most familiar rock formation . The granite crest rises more than 4,737 ft (1,444 m) above

1221-454: The sides of a glacier. The unconsolidated debris can be deposited on top of the glacier by frost shattering of the valley walls or from tributary streams flowing into the valley, or may be subglacial debris carried to the surface of the glacier, melted out, and transported to the glacier margin. Lateral moraines can rise up to 140 meters (460 ft) over the valley floor, can be up to 3 kilometers (1.9 mi) long, and are steeper close to

1258-427: The snout or end of the glacier. They usually reflect the shape of the glacier's terminus . Glaciers act much like a conveyor belt, carrying debris from the top of the glacier to the bottom where it deposits it in end moraines. End moraine size and shape are determined by whether the glacier is advancing, receding or at equilibrium. The longer the terminus of the glacier stays in one place, the more debris accumulate in

1295-467: The south wall because the granite rocks of Moraine Dome and Sugar Bowl Dome are tougher and more resistant. This is remarkable considering that it is likely that Little Yosemite was not only scoured repeatedly by glaciers that were wholly contained by the canyon, but also overrun by glaciers that overflowed the Merced canyon and spread widely into surrounding uplands with occasional surges of ice contributed over

1332-419: The surface in the ablation zone , melting of surface ice or from debris that falls onto the glacier from valley sidewalls. Washboard moraines , also known as minor or corrugated moraines , are low-amplitude geomorphic features caused by glaciers. They consist of low-relief ridges, 1 to 2 meters (3 ft 3 in to 6 ft 7 in) in height and around 100 meters (330 ft) apart, accumulated at

1369-467: Was introduced into geology by Horace Bénédict de Saussure in 1779. Moraines are landforms composed of glacial till deposited primarily by glacial ice. Glacial till, in turn, is unstratified and unsorted debris ranging in size from silt -sized glacial flour to large boulders. The individual rock fragments are typically sub-angular to rounded in shape. Moraines may be found on the glacier's surface or deposited as piles or sheets of debris where

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