Ch'iyar Qullu (

Aymara Aymara may refer to: Languages and people * Aymaran languages, the second most widespread Andean language ** Aymara language, the main language within that family ** Central Aymara, the other surviving branch of the Aymara(n) family, which today ...

''ch'iyara'' black, ''qullu'' mountain, "black mountain", also spelled ''Chiar Kkollu'') is a volcanic centre in

Bolivia , image_flag = Bandera de Bolivia (Estado).svg , flag_alt = Horizontal tricolor (red, yellow, and green from top to bottom) with the coat of arms of Bolivia in the center , flag_alt2 = 7 × 7 square p ...

. It is located in the

Oruro Department Oruro (; Quechua: ''Uru Uru''; Aymara: ''Ururu'') is a department of Bolivia, with an area of . Its capital is the city of Oruro. According to the 2012 census, the Oruro department had a population of 494,178. Provinces of Oruro The departme ...

Ladislao Cabrera Province Ladislao Cabrera is a province in the southern parts of the Bolivian department of Oruro. It is named after Ladislao Cabrera (1830 – 1921). Its seat is Salinas de Garci Mendoza. Location Ladislao Cabrera is one of sixteen provinces in the Oruro ...

, Salinas de Garci Mendoza Municipality, northeast of

Salinas de Garci Mendoza Salinas de Garci Mendoza (formerly: Salinas de Thunupa) is a town in the Bolivian Oruro Department. It is the administrative center of Ladislao Cabrera Province and is located south-west of Oruro, the capital of the department. It is situated at ...

, near a

maar A maar is a broad, low-relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma). A maar characteristically fills with water to form a relatively shallow ...

named Jayu Quta ("salt lake"). It is a sill formed from primitive

phyric 300px, feldspathic phenocrysts. This granite, from the Switzerland">Swiss side of the Mont Blanc massif, has large white plagioclase phenocrysts, triclinic minerals that give trapezoid shapes when cut through). 1 euro coins, 1 euro coin (diameter ...

alkali basalt Alkali basalt or alkali olivine basalt is a dark-colored, porphyritic volcanic rock usually found in oceanic and continental areas associated with volcanic activity, such as oceanic islands, continental rifts and volcanic fields. Alkali basalt ...

that closely resembles

ocean island basalt Ocean island basalt (OIB) is a volcanic rock, usually basaltic in composition, erupted in oceans away from tectonic plate boundaries. Although ocean island basaltic magma is mainly erupted as basalt lava, the basaltic magma is sometimes modified b ...

in composition and now appears as a hill. The rocks contain

augite Augite is a common rock-forming pyroxene mineral with formula . The crystals are monoclinic and prismatic. Augite has two prominent cleavages, meeting at angles near 90 degrees. Characteristics Augite is a solid solution in the pyroxene group. ...

and

olivine The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...

and the eruption site coincides with a local lineament and is of

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

age, with dates of 22.51±0.45 mya by

Ar-Ar dating Arar or Ar-Ar may refer to: Geography and history * Arar, Saudi Arabia, the capital of Al Hudud ash Shamaliyah (The Northern Border) province ** Arar border crossing, a Saudi-Iraqi border crossing near Arar, Saudi Arabia and Nukhayb, Iraq * Arar ...

and 25.2±0.5 mya by K-Ar dating. The Ch'iyar Qullu magmas are Central Andes intraplate magmas and originate from the

upper mantle The upper mantle of Earth is a very thick layer of rock inside the planet, which begins just beneath the crust (at about under the oceans and about under the continents) and ends at the top of the lower mantle at . Temperatures range from appro ...

References

Volcanoes of Bolivia Volcanoes of Oruro Department Geology of Oruro Department Sills (geology) Miocene volcanism {{Volcanology-stub