97-588: Ubinas is an active stratovolcano in the Moquegua Region of southern Peru , approximately 60 kilometres (37 mi) east of the city of Arequipa . Part of the Central Volcanic Zone of the Andes , it rises 5,672 metres (18,609 ft) above sea level. The volcano's summit is cut by a 1.4-kilometre-wide (0.87 mi) and 150-metre-deep (490 ft) caldera , which itself contains a smaller crater . Below
194-458: A composite volcano , is a conical volcano built up by many alternating layers ( strata ) of hardened lava and tephra . Unlike shield volcanoes , stratovolcanoes are characterized by a steep profile with a summit crater and explosive eruptions. Some have collapsed summit craters called calderas . The lava flowing from stratovolcanoes typically cools and solidifies before spreading far, due to high viscosity . The magma forming this lava
291-408: A hummocky deposit on the southern flank. The sloping terrain that Ubinas is built upon predisposes the mountain to south-directed landslides; future collapses in that direction are possible, with the heavily fractured southern flank of the caldera particularly at risk. In the 1970s, an ephemeral crater lake appeared in the crater after wet seasons; another lake formed in 2016 after the crater floor
388-747: A 4-inch thick ash layer can weigh 120-200 pounds and can get twice as heavy when wet. Wet ash also poses a risk to electronics due to its conductive nature. Dense clouds of hot volcanic ash can be expelled due to the collapse of an eruptive column , or laterally due to the partial collapse of a volcanic edifice or lava dome during explosive eruptions . These clouds are known as pyroclastic surges and in addition to ash , they contain hot lava , pumice , rock , and volcanic gas . Pyroclastic surges flow at speeds over 50 mph and are at temperatures between 200 °C – 700 °C. These surges can cause major damage to property and people in their path. Lava flows from stratovolcanoes are generally not
485-456: A 65-square-kilometre (25 sq mi) circular surface at the margin of a high plateau . Volcanic ash and some lava flows cover the terrain north and east of Ubinas. Four lava domes crop out around the volcano and may be related to it. The Ubinas and Para valleys border the volcano in its southeastern sector; the difference in elevation between the floor of the Ubinas valley and the plateau
582-421: A deposit with five separate layers of pumice, ash and lapilli. More eruptions identified by tephrochronology took place 1,890 ± 70, 7,480 ± 40, 11,280 ± 70, 11,480 ± 220 and 14,690 ± 200 years ago, yielding scoria and pyroclastic flows. The various explosive eruptions of Ubinas have deposited material as far as 15 kilometres (9.3 mi) away from the volcano. Landslides also took place in this time, including
679-595: A distance of 10 kilometres (6.2 mi) from the volcano, and left a collapse scar that is drained by the Volcanmayo River . This collapse took place early in the history of the volcano and removed a volume of about 2.8 cubic kilometres (0.67 cu mi) of rock from the mountain and underlying basement. Further collapses have occurred throughout the history of the volcano and into the Holocene epoch, including one 1-cubic-kilometre (0.24 cu mi) collapse that left
776-474: A fast moving mudflow . Lahars are typically about 60% sediment and 40% water. Depending on the abundance of volcanic debris the lahar can be fluid or thick like concrete. Lahars have the strength and speed to flatten structures and cause great bodily harm, gaining speeds up to dozens of kilometers per hour. In the 1985 eruption of Nevado del Ruiz in Colombia , Pyroclastic surges melted snow and ice atop
873-515: A final intermediate composition . When the magma nears the top surface, it pools in a magma chamber within the crust below the stratovolcano. The processes that trigger the final eruption remain a question for further research. Possible mechanisms include: These internal triggers may be modified by external triggers such as sector collapse , earthquakes , or interactions with groundwater . Some of these triggers operate only under limited conditions. For example, sector collapse (where part of
970-428: A mudflow. Mudflows can be caused by unusually heavy rains or a sudden thaw. They consist mainly of mud and water plus fragments of rock and other debris, so they often behave like floods. They can move houses off their foundations or bury a place within minutes because of incredibly strong currents. When a mudflow occurs it is given four named areas, the 'main scarp', in bigger mudflows the 'upper and lower shelves' and
1067-416: A report on the activity of Ubinas. When there are indications of increased volcanic activity, it can recommend that the local government raise the volcano hazard level . Hazard maps were created during the 2006 eruptive event to show the relative risk in various locations around the volcano, which is graded in a three-zone scheme with one high-risk, one intermediate-risk and one low-risk zone. A contingency map
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#17328756976681164-739: A result of intraplate volcanism on oceanic islands far from plate boundaries. Examples are Teide in the Canary Islands , and Pico do Fogo in Cape Verde . Stratovolcanoes in the East African Rift include Ol Doinyo Lengai in Tanzania, and Longonot in Kenya. Subduction zone volcanoes form when hydrous minerals are pulled down into the mantle on the slab. These hydrous minerals, such as chlorite and serpentine , release their water into
1261-574: A significant amount of sediment, mudflows have higher flow heights than a clear water flood for the same water discharge. Also, sediment within the mudflow increases granular friction within the flow structure of the flow relative to clear water floods, which raises the flow depth for the same water discharge. Difficulty predicting the amount and type of sediment that will be included in a mudflow makes it much more challenging to forecast and engineer structures to protect against mudflow hazards compared to clear water flood hazards. Mudflows are common even in
1358-461: A significant threat to humans or animals because the highly viscous lava moves slowly enough for everyone to evacuate. Most deaths attributed to lava are due to related causes such as explosions and asphyxiation from toxic gas . Lava flows can bury homes and farms in thick volcanic rock which greatly reduces property value. However, not all stratovolcanoes erupt viscous and sticky lava . Nyiragongo , near Lake Kivu in central Africa ,
1455-477: A small size. An underground magmatic connection between Ubinas and Huaynaputina was postulated already by Antonio Vázquez de Espinosa after the 1600 eruption of the latter volcano, which was the largest historical eruption in the Andes and had an enormous impact, including causing a cold summer in the northern hemisphere. The basement of Ubinas consists of volcanic and sedimentary rocks. The sedimentary rocks include
1552-421: A vegetation form called pajonal , which consists of creeping plants, grasses and shrubs made up of high Andean vegetation. Small lakes and areas of waterlogged soil form wetlands called bofedales , in which aquatic plants and rosette-forming plants grow; both bofedales and pajonal also feature cushion plants . The upper sector of Ubinas is vegetation-free. Animal species have been described mainly in
1649-435: A wide range of sizes, which typically become sorted by size upon deposition. Mudflows are often called mudslips , a term applied indiscriminately by the mass media to a variety of mass wasting events. Mudflows often start as slides, becoming flows as water is entrained along the flow path; such events are often called mud failures . Other types of mudflows include lahars (involving fine-grained pyroclastic deposits on
1746-523: Is arid overall, but during the summer wet-season rainfall can cause landslides at lower elevation, and the upper parts of the volcano including the caldera can receive a snow cover. Weather data are available for the town of Ubinas at 3,200 metres (10,500 ft) elevation: the average temperature is 9–11 °C (48–52 °F) and the average annual precipitation is about 300–360 millimetres per year (12–14 in/year). The present-day snow line exceeds 5,400 metres (17,700 ft) elevation, but during
1843-415: Is a conical, truncated stratovolcano with upper slopes that reach angles of up to 45 degrees, and more gently sloping lower flanks. The more gently sloping lower part of the volcano is also known as Ubinas I and the steeper upper part as Ubinas II. The southern flank is cut by a noticeable notch, which is probably not an eruption vent and may have been formed by mudflows and rockslides . Due to weathering ,
1940-431: Is a form of mass wasting involving fast-moving flow of debris and dirt that has become liquified by the addition of water. Such flows can move at speeds ranging from 3 meters/minute to 5 meters/second. Mudflows contain a significant proportion of clay, which makes them more fluid than debris flows , allowing them to travel farther and across lower slope angles. Both types of flow are generally mixtures of particles with
2037-527: Is a passive release of gas during periods of dormancy. As per the above examples, while eruptions like Mount Unzen have caused deaths and local damage, the impact of the June 1991 eruption of Mount Pinatubo was seen globally. The eruptive columns reached heights of 40 km and dumped 17 megatons of SO 2 into the lower stratosphere . The aerosols that formed from the sulfur dioxide (SO 2 ), carbon dioxide (CO 2 ), and other gases dispersed around
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#17328756976682134-408: Is about 2 kilometres (1.2 mi). The total volume of the mountain is estimated to be about 56 cubic kilometres (13 cu mi). The summit of the volcano is an elliptical caldera 1.4 kilometres (0.87 mi) wide and 150 metres (490 ft) deep, formed by collapses of the summit and explosive eruptions . The caldera walls are made of lava flows bearing traces of hydrothermal alteration;
2231-654: Is formed by the partial melting of the mantle after fluids originating in the downgoing slab have altered the mantle; the magmas often undergo fractional crystallization and absorb crustal material. Southern Peru has been affected by volcanic activity since the Ordovician and the Permian - Jurassic period, subduction -related volcanism becoming important from the Cretaceous onwards. Beginning 91 million years ago, several volcanic arcs have been active in southern Peru: from
2328-528: Is likely that the summit caldera formed during this time period, before 9,700 years ago. Over the last 7,500 years, volcanic activity has been characterized mainly by various kinds of explosive eruptions. These eruptions have expelled less than 0.1 cubic kilometres (0.024 cu mi) of material each time and left widespread deposits of ash, volcanic blocks and lapilli . A Plinian eruption occurred 980 ± 60 years BP and expelled 2.8 cubic kilometres (0.67 cu mi) of pumice and tephra, which has formed
2425-432: Is located in steep mountain channels. The 2006 Sidoarjo mud flow may have been caused by rogue drilling. The point where a muddy material begins to flow depends on its grain size, the water content, and the slope of the topography. Fine grained material like mud or sand can be mobilized by shallower flows than a coarse sediment or a debris flow. Higher water content (higher precipitation/overland flow) also increases
2522-524: Is monitored by the Peruvian geological service INGEMMET , which has published a volcano hazard map for Ubinas and regular volcanic activity reports. The historian and geographer Mariano Felipe Paz Soldán relates the name Ubinas to two terms in two different languages. In the indigenous language Quechua , uina means "to stuff" or "to fill", and uiña is translated as "to grow" or "to increase". In Aymara , hupi means "weep" or "murmur"; hupina
2619-476: Is often felsic , having high to intermediate levels of silica (as in rhyolite , dacite , or andesite ), with lesser amounts of less viscous mafic magma . Extensive felsic lava flows are uncommon, but can travel as far as 8 km (5 mi). The term composite volcano is used because the strata are usually mixed and uneven instead of neat layers. They are among the most common types of volcanoes; more than 700 stratovolcanoes have erupted lava during
2716-432: Is steeper and rises 900 metres (3,000 ft) above the Ubinas I shield. It consists mainly of 20–40-metre-thick (66–131 ft) lava flows but also several lava domes with accompanying block-and-ash flows, all of which formed between 261,000 ± 10,000 and 142,000 ± 30,000 years ago. A lack of more recent volcanic outcrops suggests a period of dormancy lasting until 25,000–14,700 years ago during which glaciation took place on
2813-634: Is the genitive of hupi . Local inhabitants believed that Ubinas was infested by demons and the souls of people who had fallen from God. The volcano is also known as Uvillas or Uvinas. Ubinas lies in the Ubinas District of the General Sánchez Cerro Province , Moquegua Region of Peru , 60 kilometres (37 mi) east of Arequipa in the Peruvian Western Cordillera . Like other Peruvian volcanoes, Ubinas belongs to
2910-451: Is the most famous example of a hazardous stratovolcano eruption. It completely smothered the nearby ancient cities of Pompeii and Herculaneum with thick deposits of pyroclastic surges and pumice ranging from 6–7 meters deep. Pompeii had 10,000-20,000 inhabitants at the time of eruption. Mount Vesuvius is recognized as one of the most dangerous of the world's volcanoes, due to its capacity for powerful explosive eruptions coupled with
3007-450: Is typically between 700 and 1,200 °C (1,300-2,200 °F). Volcanic bombs are masses of unconsolidated rock and lava that are ejected during an eruption. Volcanic bombs are classified as larger than 64mm (2.5 inches). Anything below 64mm is classified as a volcanic block . When erupted Bombs are still molten and partially cool and solidify on their descent. They can form ribbon or oval shapes that can also flatten on impact with
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3104-403: Is very dangerous because its magma has an unusually low silica content , making it much less viscous than other stratovolcanoes. Low viscosity lava can generate massive lava fountains , while lava of thicker viscosity can solidify within the vent, creating a volcanic plug . Volcanic plugs can trap gas and create pressure in the magma chamber, resulting in violent eruptions. Lava
3201-517: The 2014 Iquique earthquake , culminating in an explosive eruption on April 19, 2014. Volcanic activity decreased afterwards until September 2014. The eruptions were accompanied by earthquakes, rumbling noises from the volcano, ash fall and the forceful ejection of large blocks. In light of the volcanic activity, Peru declared a state of emergency in August 2013 and evacuated the village of Querapi at Ubinas, whose population returned in 2016; The evacuation of
3298-1077: The Central Volcanic Zone of the Andes. The Central Volcanic Zone is one of four volcanic belts in the Andes; the others are the Northern Volcanic Zone , the Southern Volcanic Zone , and the Austral Volcanic Zone . The Central Volcanic Zone is 1,500 kilometres (930 mi) long, and 69 of its volcanoes have been active in the Holocene epoch. Peruvian volcanoes include stratovolcanoes , which are typically active for less than 500,000 years, long-lived clusters of lava domes, and monogenetic volcanic fields . Historical eruptions have been recorded at seven Peruvian volcanoes: El Misti , Huaynaputina , Sabancaya , Ticsani , Tutupaca , Ubinas, and Yucamane . The volcanoes Ampato , Casiri , Chachani , Coropuna , and Sara Sara are dormant . Reaching an elevation of 5,672 metres (18,609 ft), Ubinas
3395-800: The Holocene Epoch (the last 11,700 years), and many older, now extinct, stratovolcanoes erupted lava as far back as Archean times. Stratovolcanoes are typically found in subduction zones but they also occur in other geological settings. Two examples of stratovolcanoes famous for catastrophic eruptions are Krakatoa in Indonesia (which erupted in 1883 claiming 36,000 lives) and Mount Vesuvius in Italy (which erupted in 79 A.D killing an estimated 2,000 people). In modern times, Mount St. Helens (1980) in Washington State , US, and Mount Pinatubo (1991) in
3492-728: The Jurassic Chocholate Formation , the Socosani Formation and the Yura Group . The oldest volcanic rocks of the Matalaque Volcanics date to the Late Cretaceous and crop out east and southeast of Ubinas, far away from the volcano. Most of the volcanics in proximity to Ubinas are the younger, Eocene -to- Oligocene Tacaza Group and the more restricted Miocene - Pliocene Barroso Group , which directly underlies
3589-573: The Philippines have erupted catastrophically, but with fewer deaths. Stratovolcanoes are common at subduction zones , forming chains and clusters along plate tectonic boundaries where an oceanic crust plate is drawn under a continental crust plate (continental arc volcanism, e.g. Cascade Range , Andes , Campania ) or another oceanic crust plate ( island arc volcanism, e.g. Japan , Philippines , Aleutian Islands ). Stratovolcanoes also occur in some other geological settings, for example as
3686-460: The Pleistocene epoch it descended to about 4,900 metres (16,100 ft). Vegetation at 3,400–4,200 metres (11,200–13,800 ft) elevation consists of grassland, bushes and low trees such as Buddleja coriacea , Escallonia myrtilloides , Polylepis besseri and Ribes brachybotrys forming a shrub vegetation in valleys. Farther up, between 4,200–4,700 metres (13,800–15,400 ft) lies
3783-459: The Puno and Tacna Regions , as well as Bolivia and Argentina . Since then the volcano has been active with ash and steam emissions, earthquakes and lahars. In May 2023, an increase of seismic activity preceded a new eruption that commenced on 22 June 2023. This eruption petered out at the end of the year, while lahars descended its slopes. Hazards stemming from volcanic activity at Ubinas are mainly
3880-577: The hills around Los Angeles , California, where they have destroyed many homes built on hillsides without sufficient support after fires destroy vegetation holding the land. On 14 December 1999 in Vargas , Venezuela , a mudflow known as The Vargas tragedy significantly altered more than 60 kilometers (37 mi) of the coastline. It was triggered by heavy rainfall and caused estimated damages of US$ 1.79 to US$ 3.5 billion, killed between 10,000 and 30,000 people, forced 85,000 people to evacuate , and led to
3977-891: The magma is too viscous to allow easy escape of volcanic gases . As a consequence, the tremendous internal pressures of the trapped volcanic gases remain and intermingle in the pasty magma . Following the breaching of the vent and the opening of the crater, the magma degasses explosively. The magma and gases blast out with high speed and full force. Since 1600 CE , nearly 300,000 people have been killed by volcanic eruptions . Most deaths were caused by pyroclastic flows and lahars , deadly hazards that often accompany explosive eruptions of subduction-zone stratovolcanoes. Pyroclastic flows are swift, avalanche-like, ground-sweeping, incandescent mixtures of hot volcanic debris, fine ash , fragmented lava , and superheated gases that can travel at speeds over 150 km/h (90 mph). Around 30,000 people were killed by pyroclastic flows during
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4074-443: The mantle which decreases its melting point by 60 to 100 °C. The release of water from hydrated minerals is termed " dewatering ", and occurs at specific pressures and temperatures for each mineral, as the plate descends to greater depths. This allows the mantle to partially melt and generate magma . This is called flux melting . The magma then rises through the crust , incorporating silica-rich crustal rock, leading to
4171-488: The 'toe'. The main scarp will be the original area of incidence, the toe is the last affected area(s). The upper and lower shelves are located wherever there is a large dip (due to mountain or natural drop) in the mudflow's path. A mudflow can have many shelves. The world's largest historic subareal (on land) landslide occurred during the 1980 eruption of Mount St. Helens , a volcano in the Cascade Mountain Range in
4268-869: The 1 cubic kilometre (0.24 cu mi) collapse more than 3,670 ± 60 years ago. Ubinas is the most active volcano in Peru and one of the most active in the Central Volcanic Zone; as of 2023 at least 27 explosive eruptions have occurred since the 16th century at an average rate of one eruption every twenty to thirty-three years. Events are recorded from 1550, 1599, 1600, 1662, 1667, 1677, 1778, 1784, 1826, 1830, 1862, 1865, 1867, 1869, 1906, 1907, 1912, 1923, 1936, 1937, 1951, 1956, 1969, 1996, 2006–2009, 2013–2016, 2016–2017 and 2019. Most of these eruptions consisted of emissions of ash and gas, sometimes accompanied by explosions, while more intense events such as in 1667 also produced scoria falls and pyroclastic flows. The 1667 eruption
4365-607: The 1902 eruption of Mount Pelée on the island of Martinique in the Caribbean . During March and April 1982, El Chichón in the State of Chiapas in southeastern Mexico , erupted 3 times, causing the worst volcanic disaster in that country's history and killied more than 2,000 people in pyroclastic flows . Two Decade Volcanoes that erupted in 1991 provide examples of stratovolcano hazards. On 15 June, Mount Pinatubo erupted and caused an ash cloud to shoot 40 km (25 mi) into
4462-481: The 1982 eruption of Galunggung in Java , British Airways Flight 9 flew into the ash cloud, causing it to sustain temporary engine failure and structural damage. Although no crashes have happened due to ash, more than 60, mostly commercial aircraft , have been damaged. Some of these incidents resulted in emergency landings. Ashfalls are a threat to health when inhaled and are also a threat to property. A square yard of
4559-464: The 2006–2007 eruption sequence involved the ejection of large volcanic bombs at high speed and the emission of small quantities of ash. Gas and ash columns were emitted between April and October 2006 and reached heights of about 3–4 kilometres (1.9–2.5 mi). Volcanically induced melting of snow that had fallen on the summit during the 2006–2007 summer induced a mudflow in January 2007 that descended into
4656-585: The 5,321 m (17,457 ft) high Andean volcano. The ensuing lahar killed 25,000 people and flooded the city of Armero and nearby settlements. As a volcano forms, several different gases mix with magma in the volcanic chamber. During an eruption the gases are then released into the atmosphere which can lead to toxic human exposure. The most abundant of these gases is H 2 O ( water ) followed by CO 2 ( carbon dioxide ), SO 2 ( sulfur dioxide ), H 2 S ( hydrogen sulfide ), and HF ( hydrogen fluoride ). If at concentrations of more than 3% in
4753-440: The State of Washington , US The volume of material displaced was 2.8 km (0.67 cu mi). Directly in the path of the huge mudflow was Spirit Lake . Normally a chilly 5 °C (41 °F), the lahar instantly raised the temperature to near 38 °C (100 °F). Today the bottom of Spirit Lake is 100 ft (30 m) above the original surface, and it has two and a half times more surface area than it did before
4850-578: The Toquepala arc 91 – c. 45 million years ago over the Andahuaylas-Anta c. 45–30 million years ago, the Huaylillas 24–10 million years ago, the two Barroso arcs 10–1 million years ago, to the recent arc in the last million years. The switching between the volcanic arcs was accompanied by northeastward or southwestward shifts of the zone of main volcanic activity. Furthermore, there was little relief in
4947-552: The Ubinas River valley. Volcanic activity— degassing and of Vulcanian eruptions —decreased until late 2009. This eruption was probably triggered by the entry of fresh magma in the magma plumbing system and the subsequent interaction of ascending magmas with the hydrothermal system of Ubinas. Beginning in July 2009, eruptive activity decreased considerably, being replaced with steady fumarolic emissions. Despite its record of activity, Ubinas
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#17328756976685044-435: The Ubinas mountain. Even older basement rocks include Paleoproterozoic plutons and the sedimentary Yura Group of Jurassic to Cretaceous age. A depression, whose margin is cut by landslide scars, cuts into the basement southeast of Ubinas and contains the Ubinas valley. Faults cut across the volcano and create unstable areas, especially in its southern sector, and NNW-SSE trending geological lineaments have influenced
5141-816: The air, when breathed in CO 2 can cause dizziness and difficulty breathing. At more than 15% concentration CO 2 causes death. CO 2 can settle into depressions in the land, leading to deadly, odorless pockets of gas. SO 2 classified as a respiratory, skin, and eye irritant if come into contact with. It is known for its pungent egg smell and role in ozone depletion and has the potential to cause acid rain downwind of an eruption. H 2 S has an even stronger odor than SO 2 as well as being even more toxic. Exposure for less than an hour at concentrations of over 500 ppm causes death. HF and similar species can coat ash particles and once deposited can poison soil and water. Gases are also emitted during volcanic degassing, which
5238-741: The air. It produced large pyroclastic surges and lahar floods that caused a lot of damage to the surrounding area. Pinatubo , located in Central Luzon just 90 km (56 mi) west-northwest of Manila , had been dormant for six centuries before the 1991 eruption. This eruption was one of the 2nd largest in the 20th century. It produced a large volcanic ash cloud that affected global temperatures, lowering them in areas as much as .5 °C. The volcanic ash cloud consisted of 22 million tons of SO 2 which combined with water droplets to create sulfuric acid . In 1991 Japan's Unzen Volcano also erupted, after 200 years of inactivity. It's located on
5335-426: The caldera floor is covered by lava flows and pyroclastic debris from explosive eruptions. It contains one or two ash cones with a triangle-shaped crater 400 metres (1,300 ft) wide and 300 metres (980 ft) deep; its walls are fractured and hydrothermally altered. Geophysical surveys have indicated the presence of an even larger buried caldera in Ubinas. A debris avalanche on the southeastern flank reached
5432-426: The closest town to it. Agriculture and animal husbandry are the most important economic activities in these towns, agriculture prevailing at lower elevations. Water reservoirs and mining projects also exist in the wider region. Paved roads run along the northern and southern-southwestern foot of Ubinas, connecting towns close to the volcano to Arequipa and allowing access to the volcano over its western flank. Off
5529-408: The complete collapse of the state's infrastructure. Landslide is a more general term than mudflow. It refers to the gravity-driven failure and subsequent movement downslope of any types of surface movement of soil, rock, or other debris. The term incorporates earth slides, rock falls, flows, and mudslides, amongst other categories of hillslope mass movements . They do not have to be as fluid as
5626-554: The context of the National Reserve; they include various birds and camelids such as alpacas , guanacos , llamas and vicuñas . Sulfur deposits in the crater of Ubinas were considered among the most important sulfur deposits in Peru and were mined in the 19th century. Ubinas has been considered a potential place for geothermal energy production. Its eruptions between 2006–2017 have stimulated research on this volcano. Stratovolcano A stratovolcano , also known as
5723-451: The crater. Ubinas persistently emanates smoke, and lahars which have damaged fields , irrigation canals and paths have been recorded, such as the 2016 lahars caused by early 2016 precipitation events which mobilized ash that had fallen over the previous years. These lahars destroyed local water supplies and left the Matalaque and Ubinas districts temporarily isolated. The first episode of
5820-627: The districts surrounding the volcano, then in September of the same year an eruption generated a 4-kilometre-high (2.5 mi) eruption column that produced ash fall in the region, leading to evacuations. On 18 June 2019, earthquake activity increased and a new eruption commenced on 24 June, with eruption columns rising 5 kilometres (3.1 mi) above the summit crater. The most energetic eruption episode took place on 19 July 2019 with three major explosions. The explosions and ash emissions triggered evacuations and impacted 29,703 people in various districts of
5917-511: The eruption. The largest known of all prehistoric landslides was an enormous submarine landslide that disintegrated 60,000 years ago and produced the longest flow of sand and mud yet documented on Earth. The massive submarine flow travelled 1,500 km (930 mi) – the distance from London to Rome. By volume, the largest submarine landslide (the Agulhas slide off South Africa) occurred approximately 2.6 million years ago. The volume of
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#17328756976686014-408: The fallout from explosive eruptions, lahars of different origins, large landslides that can generate debris flows and pyroclastic flows. Small explosive eruptions are the most likely occurrences at Ubinas, while large Plinian eruptions are considerably less likely. The area of the cone itself is the area most likely to be affected by volcanic phenomena, while pyroclastic flows and lahars are a danger for
6111-540: The flank of a volcano collapses in a massive landslide) can only trigger the eruption of a very shallow magma chamber . Magma differentiation and thermal expansion also are ineffective as triggers for eruptions from deep magma chambers . In recorded history , explosive eruptions at subduction zone ( convergent-boundary ) volcanoes have posed the greatest hazard to civilizations. Subduction-zone stratovolcanoes, such as Mount St. Helens , Mount Etna and Mount Pinatubo , typically erupt with explosive force because
6208-656: The flanks of volcanoes) and jökulhlaups (outbursts from under glaciers or icecaps). A statutory definition of "flood-related mudslide" appears in the United States' National Flood Insurance Act of 1968, as amended, codified at 42 USC Sections 4001 and following. Heavy rainfall, snowmelt , or high levels of groundwater flowing through cracked bedrock may trigger a movement of soil or sediments in landslides that continue as mudflows. Floods and debris flows may also occur when strong rains on hill or mountain slopes cause extensive erosion and/or mobilize loose sediment that
6305-490: The foot of the volcano and debris and ignimbrite deposits in the south and southeast of Ubinas, and it forms a 600-metre-high (2,000 ft) shield . It was later cut on its southern side by a debris avalanche that probably occurred over 376,000 years ago. The last activity of Ubinas I generated more than four units of pyroclastic flows , with a total volume of about 1.8 cubic kilometres (0.43 cu mi), and possibly an old caldera 269,000 ± 16,000 years ago. Ubinas II
6402-453: The genesis of this magma suite. Lava composition has changed over time, dacites being represented mainly during the Ubinas II stage while stage I yielded mostly andesites. Silica content has decreased over time, with two phases of more silicic eruptions in the mid- and late Holocene. Holocene explosive eruptions were fed by silicic magma chambers that are now inactive as basaltic andesite is
6499-478: The ground. Volcanic Bombs are associated with Strombolian and Vulcanian eruptions and basaltic lava . Ejection velocities ranging from 200 to 400 m/s have been recorded causing volcanic bombs to be destructive. Lahars (from a Javanese term for volcanic mudflows) are a mixture of volcanic debris and water. Lahars can result from heavy rainfall during or before the eruption or interaction with ice and snow. Meltwater mixes with volcanic debris causing
6596-458: The high population density of the surrounding Metropolitan Naples area (totaling about 3.6 million inhabitants). In addition to potentially affecting the climate, volcanic ash clouds from explosive eruptions pose a serious hazard to aviation . Volcanic ash clouds consist of ash which is made of silt or sand sized pieces of rock, mineral, volcanic glass . Ash grains are jagged, abrasive, and don't dissolve in water. For example, during
6693-500: The island of Kyushu about 40 km (25 mi) east of Nagasaki . Beginning in June, a newly formed lava dome repeatedly collapsed. This generated a pyroclastic flow that flowed down the mountain's slopes at speeds as high as 200 km/h (120 mph). The 1991 eruption of Mount Unzen was one of the worst volcanic disasters in Japan's history, once killing more than 15,000 people in 1792. The eruption of Mount Vesuvius in 79 AD
6790-538: The major product of historical eruptions. There is a trend for more recent volcanic events to produce more diverse rocks than the early eruptions, probably owing to a change in the magma supply regime; after 25,000–14,700 years ago magma supply increased and became more irregular. Otherwise, the magma supply rate at Ubinas amounts to about 0.18–0.13 cubic kilometres per millennium (0.043–0.031 cu mi/ka), with an average rate of 0.15 cubic kilometres per millennium (0.036 cu mi/ka). Ubinas started to develop in
6887-422: The middle and late Pleistocene epoch. The oldest pre-Ubinas volcanics crop out north and south of the volcano and include the volcanoes Parhuane Grande and Parhuane Chico directly to the north. Volcanic activity started after a change in regional tectonics, which may have triggered the formation of magma chambers. The volcano developed in two phases, Ubinas I and Ubinas II: Ubinas I is represented by lava flows at
6984-434: The nights. Fumarolic activity and degassing is limited to the crater; there is no evidence of such gas exhalations elsewhere on the volcano. Ubinas is a major source of volcanic carbon dioxide and sulfur dioxide in the atmosphere of Earth, producing SO 2 at a rate of about 11.4 ± 3.9 kilograms per second (1,510 ± 520 lb/min). The sulfur dioxide output changes with volcanic activity. Reportedly,
7081-754: The potential to initiate a mudflow. After a mudflow forms, coarser sediment may be picked up by the flow. Coarser sediment picked up by the flow often forms the front of a mudflow surge and is pushed by finer sediment and water that pools up behind the coarse-grained moving mudflow-front. Mudflows may contain multiple surges of material as the flow scours channels and destabilizes adjacent hillslopes (potentially nucleating new mudflows). Mudflows have mobilized boulders 1–10 m across in mountain settings. Some broad mudflows are rather viscous and therefore slow; others begin very quickly and continue like an avalanche . They are composed of at least 50% silt and clay-sized materials and up to 30% water. Because mudflows mobilize
7178-495: The region are considered to be part of a geothermal province known as "Ubinas" which also includes El Misti, and which deliver large amounts of dissolved minerals including arsenic to the local rivers. The climate of the area changes with elevation. The summit of Ubinas has a cold climate with temperatures frequently falling below 0 °C (32 °F); at lower elevations temperatures can exceed 18 °C (64 °F) during daytime, but night frosts are still possible. The region
7275-476: The region around the volcano, resulting in about US$ 1,000,000 of damage and the flight of local residents to Arequipa and Moquegua . The village of Querapi on the southern flank was temporarily evacuated to a location with shelters farther south, and two shelters were designated in low-risk areas around the volcano, one at Anascapa and the other at Chacchagen, 1.5 kilometres (0.93 mi) away from Matalaque. Furthermore, Lake Salinas , an important source of water in
7372-481: The region before about 45 million years ago when major uplift commenced. Ubinas, Ticsani and Huaynaputina form a group of volcanoes that extend in north-south direction north of the chain of volcanoes that make up the rest of the Central Volcanic Zone. These volcanoes have erupted rocks with similar geochemical traits and they are located around a graben occupied by the Rio Tambo; the marginal faults of this graben are
7469-412: The region, was threatened by the eruption. A new eruption period started on 2 September 2013 with a phreatic explosion , which was followed by more events in the next few days. Strong but variable seismic activity, the observation of thermal anomalies in satellite images and the exhalation of gases characterized this eruption period. Lava effusion began in the summit crater in 2014 and increased after
7566-406: The sites of the volcanic vents and probably acted as magma conduits. The magmas erupted by all three volcanoes appear to originate in a common magma chamber at 20–35 kilometres (12–22 mi) depth, with seismic activity localized along the margins of the chamber. Aside from this deep reservoir, Ubinas also has a shallower magma chamber at 4–7 kilometres (2.5–4.3 mi) depth which appears to have
7663-460: The size of Mount Pinatubo affected the weather for a few years; with warmer winters and cooler summers observed. A similar phenomenon occurred in the April 1815, the eruption of Mount Tambora on Sumbawa island in Indonesia . The Mount Tambora eruption is recognized as the most powerful eruption in recorded history. Its eruption cloud lowered global temperatures as much as 0.4 to 0.7 °C. In
7760-699: The slopes of Ubinas are the Quebrada Infiernillo on the southeastern, Volcanmayo River on the southern and Quebrada Postcone on the southwestern flank. The Sacuaya River becomes the Ubinas River and after confluence with the Para ends in the Tambo River which eventually flows into the Pacific Ocean ; the Ubinas River valley is densely inhabited. Ubinas lies in the Salinas y Aguada Blanca National Reserve of Peru, which
7857-466: The sound of the fumaroles can be heard from the village of Ubinas. The fumaroles along with the spontaneous potential of Ubinas indicate that the volcano hosts an active hydrothermal system 1–3 kilometres (0.62–1.86 mi) below the caldera. About 41 springs occur in the area; of these two are hot springs , are found on the southeastern slopes of Ubinas and are known as Ubinas Termal and Ubinas Fria. Both lie at 3,267 metres (10,719 ft) elevation,
7954-574: The stability and the hydrothermal system of Ubinas. Andesite and dacite are the dominant components of the volcano, though its rocks have compositions ranging from basaltic andesite to rhyolite . The volcanic rocks form a potassium -rich calc-alkaline suite. Phenocryst minerals vary between volcanic rocks of different composition and include amphibole , apatite , biotite , clinopyroxene , iron - titanium oxides , olivine , orthopyroxene , plagioclase and zircon . Assimilation of crustal material and fractional crystallization are involved in
8051-506: The summit, Ubinas has the shape of an upwards-steepening cone with a prominent notch on the southern side. The gently sloping lower part of the volcano is also known as Ubinas I and the steeper upper part as Ubinas II; they represent different stages in the volcano's geological history. The most active volcano in Peru, Ubinas has a history of small to moderate explosive eruptions as well as a few larger eruptions, such as in 1667, along with persistent degassing and ash emissions . Activity at
8148-414: The town of Ubinas was also considered. The 2006 and 2013–2017 activity induced the Peruvian government to invest additional resources in volcano monitoring. After these events, in 2015–2017 the volcano often persistently released ash and gas, accompanied by earthquakes as well as occasional explosions and eruption columns . In April 2015, for example, activity at Ubinas led to a declaration of emergency for
8245-421: The upper sector of the volcano has a worn appearance. Glacial valleys such as the Ubinas and Para valleys, as well as cirques and moraines down to 4,000 metres (13,000 ft) and at the foot of the volcano, indicate that glaciers developed on Ubinas during the last glacial maximum . Other volcanic cones in the region all show heavy erosion by glaciation. The volcano rises 1.4 kilometres (0.87 mi) from
8342-461: The valleys that drain Ubinas in southeastern direction and landslides are hazardous for an area of the southern flank. The town closest to the volcano is only 4 kilometres (2.5 mi) away from Ubinas. Large Plinian eruptions could have effects on the city of Arequipa. The Volcano Observatory of INGEMMET monitors the seismic activity, any deformation and emissions of the mountain, and hot spring and gas composition at Ubinas. It regularly publishes
8439-441: The volcano began in the Pleistocene epoch, and led to the growth of the current mountain in two phases. Among the recent eruptions was the 2006–2007 event, which produced eruption columns and led to ash fall in the region, resulting in health issues and evacuations. During the most recent activity, from 2013 to 2017, a lava flow formed inside the crater, and further ash falls led to renewed evacuations of surrounding towns. Ubinas
8536-503: The volcano. Reactivated volcanic activity started between 25,000 and 14,700 years ago and led to the emplacement of ash flows, pumice layers and tephra from phreatomagmatic and explosive eruptions, with deposits having thicknesses ranging from 2–4 metres (6 ft 7 in – 13 ft 1 in) in many places. The total volume of each eruption deposit ranges from 1–2 cubic kilometres (0.24–0.48 cu mi) and they crop out as far as 35 kilometres (22 mi) from Ubinas. It
8633-406: The waters flowing out of the springs have temperatures of 29.1 °C (84.4 °F) and 13.6 °C (56.5 °F), respectively. The composition of the waters in these springs indicate that they originate from the mixing of deep saline water, fresh water and volcanic fluids. Additional springs associated with the volcano are Baños de Cura, Exchaje, Huarina and Lucca; these hot springs and others in
8730-635: The western coast of South America, the Nazca Plate subducts beneath the South American Plate at a rate of 7–9 centimetres per year (2.8–3.5 in/year) in the Peru-Chile Trench . This subduction process is responsible for the formation of the Andes and the Altiplano - Puna plateau within the last 25 million years, as well as for volcanism and earthquakes . The magma erupted by the volcanoes
8827-412: The world. The SO 2 in this cloud combined with water (both of volcanic and atmospheric origin) and formed sulfuric acid , blocking a portion of the sunlight from reaching the troposphere . This caused the global temperature to decrease by about 0.4 °C (0.72 °F) from 1992 to 1993. These aerosols caused the ozone layer to reach the lowest concentrations recorded at that time. An eruption
8924-469: The year following the eruption, most of the Northern Hemisphere experienced cooler temperatures during the summer. In the northern hemisphere , 1816 was known as the " Year Without a Summer ". The eruption caused crop failures, food shortages, and floods that killed over 100,000 people across Europe , Asia , and North America . Mudflow A mudflow , also known as mudslide or mud flow ,
9021-471: Was covered by the ongoing eruptions with impermeable material. Acid springs occur in the crater, and their water is capable of corroding silicon after a few hours' exposure. Lake Piscococha is located on the volcano's western foot and during December–April receives meltwater from its slopes, while the Para River and Sacuaya River flow past its eastern and southern slopes, respectively. Other rivers on
9118-420: Was created to show and explain the procedures to follow in case of various eruption scenarios. Both maps were widely disseminated after publication to aid in the response to future eruptions. Fumaroles are active at the bottom of the inner crater, with about five separate fumarole areas identified within the crater before the 2006 eruption. In 1997, a gas cloud from the fumaroles filled the entire caldera during
9215-461: Was essentially unmonitored before the 2006 event: the inhabitants of the area were largely unaware of volcanic hazards, and there were no emergency plans for future eruptions available. A "Scientific Committee" was formed on March 30, 2006 to remedy these issues. A region of about 100 square kilometres (39 sq mi) was hit by the effects of the eruption. The ash fall from the eruption caused health problems and disrupted pastures and agriculture in
9312-456: Was founded in 1979. The town of Ubinas and the villages of Querapi , Tonohaya , Ubinas and Viscachani lie southeast, south, southeast and northwest of the volcano, respectively, and other villages in the area include Anascapa, Escacha, Huarina, Huatahua, Sacuaya, San Miguel and Tonohaya. In total about 5,000 people live within 12 kilometres (7.5 mi) from the volcano, with Querapi being only 4 kilometres (2.5 mi) away from Ubinas and thus
9409-576: Was the largest in historical time, producing about 0.1 cubic kilometres (0.024 cu mi) of scoria and reaching a volcanic explosivity index of 3. These eruptions have damaged communities around the volcano, and occasionally caused epidemics and human and cattle fatalities resulting from the ingestion of ash. Aside from regular eruptions, there are fumarolic -seismic events such as in 1995–1996 when sulfur dioxide and water vapour , emitted at temperatures of up to 440 °C (824 °F), formed clouds that rose over 1 kilometre (0.62 mi) above
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