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20-469: The mountain is composed of Shuksan greenschist , oceanic basalt that was metamorphosed when the Easton terrane collided with the west coast of North America , approximately 120 million years ago. The mountain is an eroded remnant of a thrust plate formed by the Easton collision. The Mount Baker Highway , State Route 542 , is kept open during the winter to support Mt. Baker Ski Area . In late summer,

40-753: A 1907 letter to the editor of the Mazamas club journal, C. E. Rusk attributed the first ascent to Joseph Morowits in 1897. He said that he himself would have attempted it in 1903 if he had not been sure that it had already been climbed. Shuksan greenschist Greenschists are metamorphic rocks that formed under the lowest temperatures and pressures usually produced by regional metamorphism , typically 300–450 °C (570–840 °F) and 2–10 kilobars (29,000–145,000 psi). Greenschists commonly have an abundance of green minerals such as chlorite , serpentine , and epidote , and platy minerals such as muscovite and platy serpentine. The platiness gives

60-477: Is a thin layering of the rock produced by metamorphism (a foliation ) that permits the rock to easily be split into flakes or slabs less than 5 to 10 millimeters (0.2 to 0.4 in) thick. This arises from the presence of chlorite or other platy minerals that become aligned in layers during metamorphism. Greenschist may also contain albite and often has a lepidoblastic, nematoblastic or schistose texture defined primarily by chlorite and actinolite. Grain size

80-462: Is often considered associated with in occurrence include biotite, hornblende, orthoclase, muscovite and quartz. Albite was first reported in 1815 for an occurrence in Finnbo, Falun , Dalarna , Sweden . Albite is used as a gemstone , albeit semiprecious. Albite is also used by geologists as it is identified as an important rock forming mineral. There is some industrial use for the mineral such as

100-469: Is rarely coarse, due primarily to the mineral assemblage. Chlorite and to a lesser extent actinolite typically exhibit small, flat or acicular crystal habits. Greenstone is a field term for any massive mafic volcanic rock that has been altered to a greenish color by the formation of the same minerals that give the green color to greenschist, whether or not the rock displays schistosity. The term has also been used to describe any igneous intrusions into

120-486: The Barrovian Facies Sequence , and the lower-pressure Abukuma Facies Series . Temperatures of approximately 400 to 500 °C (750 to 930 °F) and depths of about 8 to 50 kilometres (5 to 31 miles) are the typical envelope of greenschist facies rocks. The equilibrium mineral assemblage of rocks subjected to greenschist facies conditions depends on primary rock composition. In greater detail

140-674: The Coal Measures Group of Scotland, to describe chamosite -rich mudstone of Early Jurassic age in Great Britain, or for nephrite or other greenish gemstones. Greenschist facies is determined by the particular temperature and pressure conditions required to metamorphose basalt to form the typical greenschist facies minerals chlorite, actinolite, and albite. Greenschist facies results from low temperature, moderate pressure metamorphism. Metamorphic conditions which create typical greenschist facies assemblages are called

160-604: The Nooksack language is Shéqsan ("high foot") or Ch’ésqen ("golden eagle"). Both the Nooksack and Lummi are indigenous tribes who have occupied the watersheds of the Nooksack Rivers and Lummi River, respectively. They are both federally recognized tribes in the United States. The first ascent of Mount Shuksan is usually attributed to Asahel Curtis and W. Montelius Price on September 7, 1906. However, in

180-517: The 'high' form. The 'high' form can be produced from the 'low' form by heating above 750 °C (1,380 °F) High albite can be found in meteor impact craters such as in Winslow, Arizona . Upon further heating to more than 1,050 °C (1,920 °F) the crystal symmetry changes from triclinic to monoclinic ; this variant is also known as 'monalbite'. Albite melts at 1,100–1,120 °C (2,010–2,050 °F). Oftentimes, potassium can replace

200-399: The crystal face. Albite often occurs as fine parallel segregations alternating with pink microcline in perthite as a result of exolution on cooling. There are two variants of albite, which are referred to as 'low albite' and 'high albite'; the latter is also known as 'analbite'. Although both variants are triclinic, they differ in the volume of their unit cell, which is slightly larger for

220-423: The formula Na Al Si 3 O 8 . It is a tectosilicate . Its color is usually pure white, hence its name from Latin , albus . It is a common constituent in felsic rocks. Albite crystallizes with triclinic pinacoidal forms. Its specific gravity is about 2.62 and it has a Mohs hardness of 6 to 6.5. Albite almost always exhibits crystal twinning often as minute parallel striations on

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240-615: The greenschist facies is subdivided into subgreenschist, lower and upper greenschist. Lower temperatures are transitional with and overlap the prehnite-pumpellyite facies and higher temperatures overlap with and include sub- amphibolite facies. If burial continues along Barrovian Sequence metamorphic trajectories, greenschist facies gives rise to amphibolite facies assemblages, dominated by amphibole and eventually to granulite facies . Lower pressure, normally contact metamorphism produces albite -epidote hornfels while higher pressures at great depth produces eclogite . Oceanic basalts in

260-418: The name, a rock must also exhibit schistosity or some foliation or layering. The rock is derived from basalt , gabbro or similar rocks containing sodium -rich plagioclase feldspar , chlorite, epidote and quartz. Greenschist is defined by the presence of the minerals chlorite , epidote , or actinolite , which give the rock its green color. Greenschists also have pronounced schistosity . Schistosity

280-477: The production and distribution of greenschist. The Moundville source has been shown to be from two localities in the Hillabee Formation of central and eastern Alabama. Albite Albite is a plagioclase feldspar mineral . It is the sodium endmember of the plagioclase solid solution series. It represents a plagioclase with less than 10% anorthite content. The pure albite endmember has

300-611: The road to Artist Point allows visitors to travel a few miles higher for a closer view of the peak. Picture Lake is accessible on the highway and reflects the mountain, making it a popular site for photography. Sulphide Creek Falls , one of the tallest waterfalls in North America, plunges off the southeastern flank of Mount Shuksan. There are four other tall waterfalls that spill off Mount Shuksan and neighboring Jagged Ridge and Seahpo Peak , mostly sourced from small snowfields and glaciers. The traditional name of Mount Shuksan in

320-582: The rock schistosity (a tendency to split into layers). Other common minerals include quartz , orthoclase , talc , carbonate minerals and amphibole ( actinolite ). Greenschist is a general field petrologic term for metamorphic or altered mafic volcanic rock . In Europe, the term prasinite is sometimes used. A greenstone is sometimes a greenschist but can also be rock types without any schistosity, especially metabasalt ( spilite ). However, basalts may remain quite black if primary pyroxene does not revert to chlorite or actinolite. To qualify for

340-785: The scarcity of blueschist preserved from before the Neoproterozoic Era 1000 Ma ago when the Earth's oceanic crust contained more magnesium than today's oceanic crust. In Minoan Crete , greenschist and blueschist were used to pave streets and courtyards between 1650 and 1600 BC. These rocks were likely quarried in Agia Pelagia on the north coast of central Crete. Across Europe, greenschist rocks have been used to make axes. Several sites, including Great Langdale in England, have been identified. A form of chlorite schist

360-400: The sodium characteristic in albite at amounts of up to 10%. When this is exceeded the mineral is then considered to be anorthoclase . It occurs in granitic and pegmatite masses (often as the variety cleavelandite ), in some hydrothermal vein deposits, and forms part of the typical greenschist metamorphic facies for rocks of originally basaltic composition. Minerals that albite

380-515: The vicinity of mid-ocean ridges typically exhibit sub-greenschist alteration. The greenstone belts of the various Archean cratons are commonly altered to the greenschist facies. These ancient rocks are noted as host rocks for a variety of ore deposits in Australia , Namibia and Canada . Greenschist-like rocks can also be formed under blueschist facies conditions if the original rock ( protolith ) contains enough magnesium . This explains

400-606: Was popular in prehistoric Native American communities for the production of axes and celts , as well as ornamental items. In the Middle Woodland period , greenschist was one of the many trade items that were part of the Hopewell culture exchange network, sometimes transported over thousands of kilometers. During the time of the Mississippian culture , the polity of Moundville apparently had some control over

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