ParÃcutin (or Volcán de ParÃcutin, also accented ParicutÃn) is a dormant scoria-cone volcano located in the Mexican state of Michoacán, near the city of Uruapan and about 322 km west of Mexico City. The volcano surged suddenly from the cornfield of local farmer Dionisio Pulido in 1943, attracting both popular and scientific attention. This eruption presented the first occasion for modern science to document the full life cycle of an eruption of this type. During the 9 year life span of ParÃcutin, scientists sketched and mapped it, took samples as well as thousands of photographs of this amazing volcano. By 1952, the volcano left a 424 meter high cone and significantly damaged a 233 km2 area with the ejection of stone, ash and lava. Only two people were killed by pyroclastic lightning, but two towns were completely evacuated and buried by lava and three others were heavily affected. Hundreds of people had to be permanently relocated, with two new towns created to accommodate the migration of people. Although the area still remains highly active volcanically, ParÃcutin itself is quiet and has become a tourist attraction, with people climbing the volcano itself and visiting the hardened-lava covered ruins of the San Juan Parangaricutiro Church.
The volcano
The ParÃcutin Volcano is located in the Mexican muncicipality of Nuevo Parangaricutiro, Michoacán, 29km west of the city of Uruapan and about 322 km west of Mexico City. It lies on the northern flank of the Cerros de TancÃtaro, on an old shield volcano and extends 3,170 meters above sea level and 424 meters above the Valley of Quitzocho-Cuiyusuru, wedged against old volcanic mountain chains and surrounded by small volcanic cones with the intervening valleys occupied by small fields and orchards or small settlements from those a few houses to those the size of towns.
It is the youngest volcano in the Western Hemisphere, and thought to be the youngest in the world. The volcano lies on and is a product of the Trans-Mexican Volcanic Belt, which runs 900km west to east across central Mexico. It includes the Sierra Nevada mountain range, (a set of extinct volcanoes) as well as thousands of cinder cones and volcanic events. Volcanic activity here has created the Central Mexican Plateau, and rock deposits up to 1.8km deep. It has also created fertile soils and some of Mexico’s most productive farmland. The volcanic activity here is a result of the subduction of the Rivera and Cocos plates along the Middle America Trench. More specifically, the volcano is the youngest of the approximately 1,400 volcanic vents of the Michoacán-Guanajuato volcanic field, a 40,000km2 basalt plateau, filled with scoria cones, like ParÃcutin, along with small shield volcanoes, maars, tuff rings and lava domes. Scoria cones are the most common type of volcano in Mexico, appearing suddenly, and building a cone-shaped mountain with steep slopes before going extinct, with ParÃcutin's immediate predecessor being Jorullo, also in Michoacán, which arose in 1759.
Currently the crater of the volcano is about 200 meters across and it is possible to both climb the volcano and walk around the entire perimeter. Although classified as extinct by scientists, it is still hot, and seeping rainwater reacts with this heat so that the cone still emits steam in various streams. However, the forces that created the volcano are still active. In 1997 there was a vigorous swarm of 230 earthquakes with five above 3.9 In the Paricutin area due to tectonic movement. There were some reports rumbling in 1995 and of black steam and rumbling in 1998. In the summer of 2006, there was another major volcanic earthquake swarm, with over 300 located near the volcano, indicating magma movement, no eruption at Paricutin anywhere else.
The eruption
ParÃcutin erupted from 1943 to 1952, unusually long for this type of volcano and with several eruptive phases. For weeks prior, residents of the area reported hearing noises similar to thunder but without clouds in the sky. This sound is consistent with deep earthquakes from the movement of magma. A later study indicates that the eruption was preceded by 21 earthquakes over 3.2 in intensity starting five weeks before the eruption. One week prior to the eruption, newspaper reported 25-30 per day. The day before the number is estimated at 300.
The eruption began on February 20, 1943, at about 4pm. The center of the activity was a cornfield near the town of ParÃcutin, owned by Dionisio Pulido. During that day, he and his family had been working their land, clearing it to prepare for spring planting. Suddenly the ground nearby where they were working swelled upward and formed a fissure between 2 and 2.5 meters across. They report that they heard hissing sounds, and smoke which smelled like rotten eggs, indicating the presence of hydrogen sulfide. Within hours, the fissure would develop into a small crater.
Pulido reported:
At 4 p.m., I left my wife to set fire to a pile of branches when I noticed that a crack, which was situated on one of the knolls of my farm, had opened . . . and I saw that it was a kind of fissure that had a depth of only half a meter. I set about to ignite the branches again when I felt a thunder, the trees trembled, and I turned to speak to Paula; and it was then I saw how, in the hole, the ground swelled and raised itself 2 or 2.5 meters high, and a kind of smoke or fine dust -- grey, like ashes -- began to rise up in a portion of the crack that I had not previously seen . . . Immediately more smoke began to rise with a hiss or whistle, loud and continuous; and there was a smell of sulfur.
He tried to find his family and oxen but they had disappeared so he rode his horse to town where he found his family and friends, happy to see him alive. The volcano grew fast and furious after this. Witness Celedonio Gutierrez, who witnessed the eruption on the first night reported:
…when night began to fall, we heard noises like the surge of the sea, and red flames of fire rose into the darkened sky, some rising 800 meters or more into the air, that burst like golden marigolds, and a rain like artificial fire fell to the ground.
On that first day, the volcano had begun strombolian pyroclastic activity and within 24 hours, there was a scorian cone fifty meters high, created by the ejection of lapilli fragments up to the size of a walnut and larger, semi molten volcanic bombs. By the end of the week, reports had the cone between 100 and 150 meters high. Soon after the start the valley was covered in smoke and ash. The nine-year activity of the volcano is divided into four stages with names that comes from the Purhépecha language. The first phase (Quitzocho) extended from February 22 to October 18, 1943, with activity concentrated in the cracks that formed in the Cuiyusuro Valley, forming the initial cone. During this time, the ejected material was mostly lapilli and bombs. In March, the eruption become more powerful,with eruptive columns that extended for several kilometers. In four months, the cone reached 200 meters and in eight months 365 meters. During this time period, there was some lava flow. On June 12, lava began to advance towards the village of Paricutin, forcing evacuations the next day. The second phase went from October 18, 1943 to January 8, 1944 and is called Sapichi, meaning child, referring to the formation of a lateral vent and other openings on the north side of the cone. Ash and bombs continued to be ejected but the new vent sent lava towards the town of San Juan Parangaricutiro, forcing its permanent evacuation. By August, the town was completely covered in lava and ash, with only the upper portions of the main church still visible. The evacuations of ParÃcutin and San Juan were able to be accomplished without loss of life, due to the slow movement of the lava. These two phases lasted just over a year and account for more than 90% of the total material ejected from the cone, as well as four-fifths (330 meters) of the final height of 424 meters from the valley floor. It also sent ash as far as Mexico City.
The third (Taqué-Ahuan) extended from January 8, 1944 to January 12, 1945 and focuses on the formation of a series of cracks on the south side of the cone as well as an increase of activity in the center. Lava flows from this time mostly extend to the west and northwest. During this period there was also the formation of a mesa now called Los Hornitos to the south.
Over the next seven years, the volcano became less active, with the ejection of ash, stone and lava coming sporadically, with periods of silence in-between. Professional geologists pulled out of the area in 1948, leaving only Celedonio Gutierrez to continue observations. The last burst of activity was recorded by him between January and February of 1952. Several eruptions occurred in succession and a three km smoke column was produced.
Scientific importance
The main scientific importance of the ParÃcutin eruption was that it was the first time that modern science was able to fully document the entire life cycle of a volcano. The event brought geologists from all over the world but the principle researchers were William F. Foshag of the Smithsonian and Dr. Jenaro Gonzalez Reyna from the Mexican government, who came about a month after the eruption started and stayed for several years. These two wrote detailed descriptions, drew sketches and maps and took samples and thousands of photographs during this time. Many of these are still used today by researchers. Foshag continued to study the volcano until his death in 1956. Between 1943 and 1948 almost fifty scientific articles were published in major journals about the volcano, with even more since then, which increased understanding of volcanism in general but particularly of scoria cone formation.
Consequences
Despite the ongoing Second World War, the eruption drew attention from around the world, with newspaper and magazine reporters, such as those from Life, coming to cover the story. Airline pilots pointed the volcano out to passengers and one Hollywood film, Captain from Castile, was shot in the area using the erupting volcano as a backdrop, and employing locals as extras. The eruption also inspired a generation of Mexican artists to depict or allude to it in their works, including Dr Atl, Diego Rivera, David Alfaro Siqueiros, Alfredo Zalce and Pablo O'Higgins.
The eruption ended in 1952, leaving a final scoria cone with a height of 424 meters from the valley floor. The eruption destroyed or heavily damaged a 233 km2 area, and almost all the vegetation within several kilometers of the crater was destroyed The volcano spread lava over 26 km2, with 52 km2 covered in volcanic sand. The town of ParÃcutin(pop.733) is completely gone and all that remains of the town of San Juan Parangaricutiro (pop. 1,895) are parts of its main church which stand out among the hardened lava flow.
No one died directly from the eruption but three people died after being struck by lightning generation by pyroclastic eruptions. The damage from the eruption affected primarily five towns in two municipalities, San Juan Parangaricutiro and Los Reyes. In addition to the two towns that were obliterated, Zacan (pop. 876), Angahuan (1,098) and Zirosto (pop. 1,314) were also heavily affected. In total, The area most affected by the eruption had a population of 5,910.
The main effect on the people of the area was the disruption of their lives and livelihood, especially during the first two years.The area most affected by the eruption had a population of 5,910, and hundreds of these were permanently evacuated. Before leaving his home for the last time, Dionisio Pulido placed a sign on the cornfield that read “This volcano is owned and operated by Dionisio Pulido.†The population of the two destroyed towns were initially moved to camps on either side of the city of Uruapan. The population of the other three towns mostly stayed in place but made adaptations to survive during the eruption. People of Angahuan and Zacan mostly stayed where they were. The population of Zirosto divided into three: those that stayed in the original location, now known as Zirosto Viejo, those who moved a few miles away to a ranch which is now is officially called Zirosto Nuevo but locally called Barranca Seca and a third group founded a completely new settlement called Miguel Silva near Ario de Rosales.
The town of San Juan Parangaricutiro was the seat of the municipality of the same name, and its destruction prompted the political reorganization and a new seat at Parangaricutiro (today generally called San Juan Nuevo), where much of the population of the old seat had been relocated, with some going to Angahuan.
The economy of the area was then and is now mostly agricultural, with population mostly Purhépecha, rural and poor. However, the eruption did cause a number of changes both social and economic to the affected areas, both to adapt to the changed landscape but also because the fame of the eruption has brought greater contact from the rest of Mexico and beyond.
The dormant volcano has become a tourist attraction, with the main access in Angahuan, from which the volcano is clearly visible. The town offers guides and horses, both to visit the ruins of the San Juan Parangaricutiro church as well as to climb the volcano itself. The volcano is part of the Pico de TancÃtaro National Park, is mostly accessible on horseback, with only the last few hundred, very steep, meters to be climbed on foot. The trek requires a guide even if horses are not used as the path is not well-marked and passes through forest, agave fields and avocado groves. Many simply visit the ruins of the church, which is easier to access, and is still a pilgrimage site, with the old altar regularly adorned with fresh candles and flowers. Nearby there are a group of stands selling local food and souvenirs.
See also
- List of volcanoes in Mexico
References
External links
- Video documentary (eng/spa) Volcano ParÃcutin (4min)
- ParÃcutin at Peakbagger.com
Posting Komentar