M. NYIRAGONGO ERUPTS IN VIRUNGA NATIONAL PARK

Today, The Grandma has been reading about Mount Nyiragongo, the active stratovolcano in the Virunga Mountains, that erupted on a day like today in 2002.

Mount Nyiragongo is an active stratovolcano with an elevation of 3,470 m in the Virunga Mountains associated with the Albertine Rift.

It is located inside Virunga National Park, in the Democratic Republic of the Congo, about 12 km north of the town of Goma and Lake Kivu and just west of the border with Rwanda. The main crater is about two kilometres wide and usually contains a lava lake. The crater presently has two distinct cooled lava benches within the crater walls -one at about 3,175 m and a lower one at about 2,975 m.

Nyiragongo's lava lake has at times been the most voluminous known lava lake in recent history. The depth of the lava lake varies considerably. A maximum elevation of the lava lake was recorded at about 3,250 m prior to the January 1977 eruption -a lake depth of about 600 m.

Following the January 2002 eruption, the lava lake was recorded at a low of about 2,600 m, or 900 m below the rim. The level has gradually risen since then.

Nyiragongo and nearby Nyamuragira are together responsible for 40 per cent of Africa's historical volcanic eruptions.

The volcano partly overlaps with two older volcanoes, Baruta and Shaheru, and is also surrounded by hundreds of small volcanic cinder cones from flank eruptions.

Nyiragongo's cone consists of pyroclastics and lava flows.

Nyiragongo's lavas are low-silica, alkali-rich, ultramafic extrusive rocks essentially free of feldspars. They range from olivine-rich melilitites through leucites to nephelinites, containing, in various proportions mainly the minerals nepheline, leucite, melilite, kalsilite, and clinopyroxene. This very low silica composition results in eruptions with unusually fluid flows. Whereas most lava flows move rather slowly and rarely pose a danger to human life, Nyiragongo's lava flows may race downhill at up to 100 km/h.

Not much is known about how long the volcano has been erupting, but since 1882, it has erupted at least 34 times, including many periods where activity was continuous for years at a time, often in the form of a churning lava lake in the crater. The existence of the lava lake had been suspected for some time but was not scientifically confirmed until 1948.

More information: Smithsonian-Global Volcanism Program

Lava lakes reformed in the crater in eruptions in 1982-1983 and 1994. Another major eruption of the volcano began on 17 January 2002, after several months of increased seismic and fumarolic activity.

A 13 kilometres fissure opened in the south flank of the volcano, spreading in a few hours from 2,800 to 1,550 metres elevation and reaching the outskirts of the city of Goma, the provincial capital on the northern shore of Lake Kivu.

Lava streamed from three spatter cones at the end of the fissure and flowed in a stream 200 to 1,000 metres wide and up to 2 metres deep through Goma. Warnings had been given and 400,000 people were evacuated from the city across the Rwandan border into neighbouring Gisenyi during the eruption.

Lava covered the northern end of the runway at Goma International Airport, leaving the southern two-thirds usable, and reached Lake Kivu. This raised fears that the lava might cause gas-saturated waters deep in the lake to suddenly rise to the surface, releasing lethally large amounts of carbon dioxide and methane -similar to the disaster at Lake Nyos in Cameroon in 1986. This did not happen, but volcanologists continue to monitor the area closely.

About 245 people died in the eruption from asphyxiation by carbon dioxide and buildings collapsing due to the lava and earthquakes.

Lava covered 13 per cent of Goma, about 4.7 km2, and nearly 120,000 people were left homeless.

Immediately after the eruption stopped, a large number of earthquakes were felt around Goma and Gisenyi. This swarm activity continued for about three months and caused the collapse of more buildings.

Six months after the start of the 2002 eruption, Nyiragongo volcano erupted again.

More information: National Geographic

Look deep into nature,
and then you will understand everything better.

Albert Einstein

MOUNT MERAPI ERUPTS IN YOGYAKARTA, INDONESIA

Today, The Grandma has been reading about Mount Merapi, the stratovolcano located in Yogyakarta, Indonesia, that erupted on a day like today in 2010.

Mount Merapi, Gunung Merapi (literally Fire Mountain in Indonesian and Javanese), is an active stratovolcano located on the border between the province of Central Java and the Special Region of Yogyakarta, Indonesia.

It is the most active volcano in Indonesia and has erupted regularly since 1548. It is located approximately 28 km north of Yogyakarta city which has a population of 2.4 million, and thousands of people live on the flanks of the volcano, with villages as high as 1,700 m above sea level.

Smoke can often be seen emerging from the mountaintop, and several eruptions have caused fatalities. A pyroclastic flow from a large explosion killed 27 people on 22 November 1994, mostly in the town of Muntilan, west of the volcano. Another large eruption occurred in 2006, shortly before the Yogyakarta earthquake. In light of the hazards that Merapi poses to populated areas, it was designated as one of the Decade Volcanoes.

On the afternoon of 25 October 2010, Merapi erupted on its southern and southeastern slopes. A total of 353 people were killed over the next month, while 350,000 were forced to flee their homes; most of the damage was done by pyroclastic flows, while heavy rain on 4 November created lahars which caused further damage. Most of the fissures had ceased erupting by 30 November, and four days later the official threat level was lowered. Merapi's characteristic shape was changed during the eruptions, with its height lowered 38 m to 2,930 m.

More information: Global Volcanism Program

Since 2010, Merapi had experienced several smaller eruptions, most noticeably two phreatic eruptions which occurred on 18 November 2013 and 11 May 2018. The first and larger of these, caused by a combination of rainfall and internal activity, saw smoke issued up to a height of 2,000 m. There have been several small eruptions since the beginning of 2020, which are of great interest to volcanologists.

The name Merapi is a compound of Sanskrit Meru meaning mountain with Javanese api which means fire. Thus Merapi can be loosely translated as Mountain of Fire or Fire Mountain.

In late October 2010, the Center for Volcanology and Geological Hazard Mitigation, Geological Agency (CVGHM), (Indonesian language-Pusat Vulkanologi & Mitigasi Bencana Geologi, Badan Geologi-PVMBG), reported that a pattern of increasing seismicity from Merapi had begun to emerge in early September.

Observers at Babadan 7 km west and Kaliurang 8 km south of the mountain reported hearing an avalanche on 12 September 2010.

On 13 September 2010, white plumes were observed rising 800 m above the crater. Lava dome inflation, detected since March, increased from background levels of 0.1 mm to 0.3 mm per day to a rate of 11 mm per day on 16 September.

On 19 September 2010, earthquakes continued to be numerous, and the next day CVGHM raised the Alert Level to 2 (on a scale of 1-4). Lava from Mount Merapi in Central Java began flowing down the Gendol River on 23-24 October signalling the likelihood of an imminent eruption.

On 25 October 2010, the Indonesian government raised the alert for Mount Merapi to its highest level (4) and warned villagers in threatened areas to move to safer ground. People living within a 10 km zone were told to evacuate. The evacuation orders affected at least 19,000 people; however, the number that complied at the time remained unclear to authorities. Officials said about 500 volcanic earthquakes had been recorded on the mountain over the weekend of 23-24 October, and that the magma had risen to about 1 km below the surface due to the seismic activity.

After a period of multiple eruptions considered to exceed the intensity and duration of those in 1872 on 10 November 2010 the intensity and frequency of eruptions was noticed to subside.

By this time, 153 people had been reported to have been killed and 320,000 were displaced. Later the eruptive activities again increased requiring a continuation of the Level 4 alert and continued provision of exclusion zones around the volcano. By 18 November the death toll had increased to 275. The toll had risen to 324 by 24 November and Syamsul Maarif, head of the National Disaster Mitigation Agency (BNPB) explained that the death toll had risen after a number of victims succumbed to severe burns and more bodies were found on the volcano's slopes.

In the aftermath of the more intensive eruptive activities in late November, Yogyakarta's Disaster Management Agency reported that there were about 500 reported cases of eruption survivors in Sleman district suffering from minor to severe psychological problems, and about 300 cases in Magelang. By 3 December the death toll had risen to 353.

Merapi is very important to Javanese, especially those living around its crater. As such, there are many myths and beliefs attached to Merapi.

More information: ESA

Those who seek power somewhere outside
rather than within themselves
should carefully look at the volcanoes!
All the power is within you!
And all you have to do is take it out!

Mehmet Murat Ildan

MOUNT PINATUBO, THE PHILIPPINE VOLCANO ERUPTS

Today, The Grandma talks about one of her greatest passions, the volcanoes. On a day like today in 1991, Mount Pinatubo erupted, generating an ash column 7 kilometres high.

Mount Pinatubo is an active stratovolcano in the Zambales Mountains, located on the tripoint boundary of the Philippine provinces of Zambales, Tarlac and Pampanga, all in Central Luzon on the northern island of Luzon.

Its eruptive history was unknown to most before the pre-eruption volcanic activities of 1991, just before June. Pinatubo was heavily eroded, inconspicuous and obscured from view. It was covered with dense forests which supported a population of several thousand indigenous Aetas.

Pinatubo is most notorious for its VEI-6 eruption on June 15, 1991, the second-largest terrestrial eruption of the 20th century after the 1912 eruption of Novarupta in Alaska.

Complicating the eruption was the arrival of Typhoon Yunya, bringing a lethal mix of ash and rain to towns and cities surrounding the volcano. Predictions at the onset of the climactic eruption led to the evacuation of tens of thousands of people from the surrounding areas, saving many lives.

Surrounding areas were severely damaged by pyroclastic surges, pyroclastic falls, and subsequently, by the flooding lahars caused by rainwater re-mobilizing earlier volcanic deposits. This caused extensive destruction to infrastructure and changed river systems for years after the eruption. Minor dome-forming eruptions inside the caldera continued from 1992 to 1993.

The effects of the 1991 eruption were felt worldwide. It ejected roughly 10 billion tonnes or 10 km3 of magma, and 20 million tonnes of SO2, bringing vast quantities of minerals and toxic metals to the surface environment. It injected more particulate into the stratosphere than any eruption since Krakatoa in 1883.

More information: EOS

Over the following months, the aerosols formed a global layer of sulphuric acid haze. Global temperatures dropped by about 0.5 °C in the years 1991-1993, and ozone depletion temporarily saw a substantial increase.

The volcano is about 87 kilometres northwest of Manila, the capital of the Philippines. Near Mount Pinatubo are former military bases that were maintained by the United States. The U.S. Naval Base Subic Bay was 37 kilometres south of Pinatubo, and the extent of Clark Air Base was just 14 kilometres  east of the volcano's summit. The volcano is near to about 6 million people.

Mount Pinatubo's summit before the 1991 eruption was 1,745 m above sea level, only about 600 m above nearby plains, and only about 200 m higher than surrounding peaks, which largely obscured it from view. It is part of a chain of volcanoes which lie along the western side of the island of Luzon called the Zambales Mountains.

Following the climactic eruption of June 15, 1991, activity at the volcano continued at a much lower level, with continuous ash eruptions lasting until August 1991 and episodic eruptions continuing for another month.

Activity at the volcano remained low until July 1992 when a new lava dome started growing in the caldera. Volcanologists suspected that further violent eruptions could be possible, and some areas were evacuated. However, the eruption was only minor. The last eruption from Mount Pinatubo took place in 1993.

More information: USGS

The word pinatubo could mean fertile place where one can make crops grow, or could mean made to grow, in Sambal and Tagalog, which may suggest a knowledge of its previous eruption in about 1500 AD. There is a local oral tradition suggestive of a folk memory of earlier large eruptions.

An ancient legend tells of Bacobaco, a terrible spirit of the sea, who could metamorphose into a huge turtle and throw fire from his mouth. In the legend, when being chased by the spirit hunters, Bacobaco flees to the mountain and digs a great hole in its summit showering the surrounding land with rock, mud, dust and fire for three days; howling so loudly that the earth shakes.

Aeta elders tell many stories about the history of the mountain, the best known being that it was once a Batung Mabye, Kapampangan language for living stone. It was said to have been planted on a kingdom by a displeased sorcerer, but relocated by a hero.

The mountain was soon turned into the abode of Apo Namalyari, The lord of happenings/events, the pagan deity of the Sambal, Aetas and Kapampangans living on the Zambales range.

It was said to comprise the whole mountain range until Sinukuan of Mount Arayat, the god of the Kapampangans, became a strong rival of Namalyari. Their fight, which took place over the center planes, shattered the mountain into smaller bodies and Mount Arayat lost its center peak. Other versions have it that Pinatubo's peak shattered because of Namalyari's immense fury in an attempt to teach humans the meaning of fear and show how misdeeds will be punished.

More information: Globe

According to the native elders, Apo Namalyari induced the June 1991 eruption because of displeasure toward illegal loggers and Philippine National Oil Company executives who performed deep exploratory drilling and well testing on the volcano looking for geothermal heat from 1988 to 1990. Discouraging results from the wells forced the abandonment of the prospect 13 months before the April 2, 1991 explosions.

After being driven away by the 1991 eruption of Mount Pinatubo, in May 2009 some 454 Aeta families in Pampanga were given the first clean ancestral land ownership on Mount Pinatubo with the Certificate of Ancestral Domain Title (CADT) by the National Commission on Indigenous Peoples (NCIP), the government agency that deals with issues concerning indigenous people of the Philippines. The approved and declared net land area of 7,440.1 ha covers the barangays of Mawakat and Nabuklod in Floridablanca, Pampanga, plus a portion of San Marcelino, Zambales, and a portion of Barangay Batiawan in Subic, Zambales.

On January 14, 2010, some 7,000 Aeta families from Zambales were officially granted the Certificate of Ancestral Domain Title (CADT) covering the Zambales side of Pinatubo which includes the summit and Lake Pinatubo, officially becoming their lutan tua (ancestral land). The ancestral domain title covers 15,984 ha and includes the villages of Burgos, Villar, Moraza and Belbel in Botolan and portions of the towns of Cabangan, San Felipe and San Marcelino.

Having the land title will protect them from others  -including foreigners- exploiting their land without compensation and consent to the indigenous tribes. In the past, the Aetas had to contend with mining companies, loggers, and recently, tourist companies who earn from Mount Pinatubo but do not compensate the local tribes.

Ancestral domain titles are awarded to a certain community or indigenous group who have occupied or possessed the land continuously in accordance with their customs and traditions since time immemorial. They have the legal right to collectively possess and to enjoy the land and its natural resources to the exclusion of others.

More information: ThoughtCo

 One volcano puts out more toxic gases  -one volcano-
than man makes in a whole year.
And when you look at this 'climate change',
and when you look at the regular climate change
that we all have in the world,
we have warm and we have cooling spells.

John Raese

HUAYNAPUTINA, THE MOST ACTIVE PERUVIAN VOLCANO

Huaynaputina

Yesterday, The Grandma had a meeting with a MEP. The content of the reunion is a secret and nobody knows anything except The Grandma and the MEP. The Grandma did not publish any post to not give any clue about this meeting but she has confessed they were talking about the future.

Today, The Grandma was resting at her hotel in Brussels thinking about yesterday when she has received news from Joseph de Ca'th Lon, one of her closest friends. He is visiting Peru and he has sent her some photos about the Huaynaputina, the famous volcano that erupted on a day like today in 1600 being the largest historical eruption in South America.

The Grandma loves volcanos and Joseph knows it. He has sent her some information about the Huaynaputina to know and study and The Grandma is totally excited with it. The eruption of the Huaynaputina buried twenty cities killing the most part of their inhabitants. For this reason, the Huaynaputina is also known as the Vesuvius of South America. This eruption changed the climate causing a global disruption.

Huaynaputina is a stratovolcano in a volcanic upland in southern Peru. Part of the Central Volcanic Zone of the Andean Volcanic Belt, it is the product of the subduction of the oceanic Nazca tectonic plate beneath the continental part of the South American tectonic plate at a rate of 10.3 centimetres per year.

Huaynaputina is a large volcanic crater, lacking an identifiable mountain profile, with an outer stratovolcano and three younger volcanic vents. The vents of Huaynaputina form a north-northwest–south-southeast trend.

More information: Smithsonian Institution

The volcano erupted several times during the Holocene, the largest eruption took place in the year 1600. The 1600 eruption was the largest historical eruption in South America, measuring 6 on the Volcanic Explosivity Index. It occurred on 19 February and continued with a series of events into March. 

Witnessed by the people of the city of Arequipa, its impact in the region was severe, wiping out vegetation and burying the surroundings with 2 metres of volcanic rock; it also damaged infrastructure and economic resources. The eruption had significant effects on Earth's climate, decreasing temperatures in the Northern Hemisphere, causing floods, famines and cold waves in numerous places, and depositing several million tons of acid. The climate disruption caused social upheaval in many countries such as Russia and may have played a role in the onset of the Little Ice Age.

Huaynaputina has not erupted since 1600. Today there are fumaroles in Huaynaputina's amphitheatre, and hot springs occur in the region, some of which have been associated with Huaynaputina. The volcano lies in a remote region, where there is little human activity.

Joseph de Ca'th Lon visits the Huaynaputina

Still, there are about 30,000 people living in the surrounding area, with another 800,000 in Arequipa. If Huaynaputina underwent a similar eruption to its 1600 event, it would likely lead to a significantly higher death toll and cause substantial socioeconomic disruption.

The name Huaynaputina was given to the volcano after its 1600 eruption and is also spelled Huayna Putina or Guagua Putina. According to one translation, Huayna means new and Putina means fire throwing mountain, the full name meant to suggest the aggressiveness of its volcanic activity but also of the 1600 eruption being the first one at that volcano. 

Two other translations are young boiling one -perhaps a reference to earlier eruptions- or where young were boiled, which may refer to human sacrifices. Other names for the volcano include Chequepuquina, Chiquimote, Guayta, Omate and Quinistaquillas. Reportedly, the volcano El Misti was sometimes confused with and thus referred to mistakenly as Huaynaputina.

The volcano is part of the Central Volcanic Zone of the Andes. Other volcanoes in this volcanic zone from northwest to southeast include Sara Sara, Coropuna, Ampato, Sabancaya, El Misti, Ubinas, Ticsani, Tutupaca and Yucamane.

More information: Hindawi

Ubinas is the most active volcano in Peru, and El Misti, Sabancaya, Ticsani, Tutupaca, Ubinas and Yucamane -as well as Huaynaputina- have been active in historical time while Sara Sara, Coropuna, Ampato, Casiri and Chachani are considered to be dormant volcanoes. Most volcanoes of the Central Volcanic Zone are large composite volcanoes that can remain active over the span of several million years, but there are also conical stratovolcanoes with shorter lifespans.

Huaynaputina is located in the Omate and Quinistaquillas Districts, which lie within General Sánchez Cerro Province in the Moquegua Region of southern Peru. The town of Omate lies 16 kilometres southwest of Huaynaputina, while the cities of Moquegua and Arequipa are located 65 km south-southwest and 80 km north-northwest of the volcano.

There is little human activity in the area near the volcano. The region is generally remote and the terrain extreme, and thus the area around Huaynaputina is not easily accessible. A cattle grazing footpath leads from Quinistaquillas to the volcano, and it is possible to approach the volcano over surrounding ash plains.

Joseph de Ca'th Lon visits the Huaynaputina

Huaynaputina lies at an elevation of about 4,850 metres. It consists of an outer composite volcano or stratovolcano and three younger volcanic vents nested within a 2.5-kilometre wide and 400-metre deep amphitheatre. This horseshoe-shaped structure is set in the older volcano at an elevation of 4,400 m and opens eastwards.

The amphitheatre lies at the margin of a rectangular high plateau that is covered by about 2-metre-thick ash over an area of 50 square kilometres. In general, the volcano has modest dimensions and rises less than 600 m above the surrounding terrain, but the products of the volcano's 1600 eruption cover much of the region to this day especially west, north and south from the amphitheatre; these include pyroclastic flow dunes that crop out from underneath the tephra.

Deposits from the 1600 eruption and previous events also crop out within the amphitheatre walls. Another southeastward-opening landslide scar lies just north of Huaynaputina.

The oceanic Nazca tectonic plate is subducting at a rate of 10.3 centimetres per year beneath the continental part of the South American tectonic plate, and this process is responsible for volcanic activity and the uplift of the Andes mountains and Altiplano plateau. The subduction is oblique, leading to strike-slip faulting. Volcanic activity does not occur along the entire length of the Andes; where subduction is shallow, there are gaps with little volcanic activity. Between these gaps lie volcanic belts: the Northern Volcanic Zone, the Central Volcanic Zone, the Southern Volcanic Zone and the Austral Volcanic Zone.

More information: Nature

Between 4,000–5,000 metres in elevation mean temperatures are about 6 °C with cold nights, while at Omate, mean temperatures reach 15 °C with little seasonal variation. Precipitation averages 154.8 millimetres per year, falling mainly during a summer wet season between December and March. This results in an arid climate, where little erosion occurs and volcanic products are well preserved. Vegetation in the area of Huaynaputina is scarce, and on the pumice deposits from the 1600 eruption it only occurs during the wet season. Cacti can be found on rocky outcrops and valley bottoms.

Based on historical records, Huaynaputina's eruption commenced on 16 February 1600, following earthquakes that began on the 15th, with the earliest signs of the impending eruption perhaps in December 1599. The event ended on 6 March with ash fall; the air was clear of ash from the eruption on 2 April 1600. Some reports of late ash falls may be due to wind-transported ash, and there are no deposits from a supposed eruption in August 1600; such reports may refer to mudflows or explosions in pyroclastic flows.

Joseph visits Estagagache in Moquegua, Peru

At first, the eruption of 1600 was attributed to Ubinas volcano and sometimes also to El Misti. Priests observed and recorded the eruption from Arequipa, and the friar Antonio Vázquez de Espinosa wrote a second-hand account of the eruption based on a witness's report from Arequipa.
 

The scale of the eruption and of its climate impact have been determined thanks to information from historical records, tree ring data, the position of glaciers, the thickness of speleothems and ice, plant flowering times, wine harvests and coral growth. Anomalies in the sun were observed after the eruption in Europe and China, often described as a dimming or reddening haze that reduced the sun's luminosity in a cloudless sky and reduced the visibility of shadows. Vivid sunsets and sunrises as well as sunspots were also noted. A darkened lunar eclipse described from Graz, Austria, in 1601 may also have been the consequence of the Huaynaputina aerosols.

Acid layers in ice cores from Antarctica and Greenland have been attributed to Huaynaputina, and their discovery led to initial discussion about whether the 1600 eruption had major effects on Earth's climate.
 

More information: Live Science

About 30,000 people live in the area of Huaynaputina today, with about 800,000 in Arequipa, and the towns of Calacoa, Omate, Puquina and Quinistaquillas and others would be threatened in case of renewed eruptions. A repeat of the 1600 eruption would likely cause a considerably greater death toll owing to population growth since 1600, in addition to causing substantial socioeconomic disruption in the Andes.

The 1600 eruption is often used as a worst case scenario model for eruptions at Peruvian volcanoes.

In 2010, earthquake activity and noises from Huaynaputina alerted the local population and led to a volcanological investigation. As part of this investigation, seismic activity was recorded around the amphitheatre; analysis showed that seismic activity was concentrated around the amphitheatre with no recorded earthquakes within it and appeared to be associated mainly with the faults and lineaments in the region.

The researchers recommended more extensive seismometer coverage of the area and regular sampling of fumaroles, as well as reconnaissance of georadar and self potential of the volcano.

In 2017, the Peruvian Geophysical Institute announced that Huaynaputina would be monitored by the future Southern Volcanological Observatory.

More information: Zurich

If I was to establish a system, it would be,

that Mountains are produced by Volcanoes,

and not Volcanoes by Mountains.

Sir William Hamilton