Volcan Telica is one of Nicaragua’s most active volcanoes. It is located along the Central American volcanic front, some 39 km NE from Volcan Momotombo on the NE edge of Lago Nicaragua. The volcano itself is constructed of at least six peaks, with Volcan Santa Clara at the SE end of the group.
The largest local town is Leon, some 20 km SSW. It currently has a population of just over 210,000 people, the second largest city in Nicaragua. The colonial town was founded in 1524 about 30 km E of its current location. It abandoned its original location after being buried by an eruption from neighboring Momotombo. It was the national capital for a time and is today the capital of the Leon Department (essentially a state or province).
There are numerous monuments and historical places in Leon. It is also home to the University of Leon, founded in 1812 among others. The local economy is primarily agriculture (cotton, sugarcane and rice), ranching (cattle), and manufacturing (cigars, shoes, saddles and other leather goods). It is linked to neighboring Managua by the Pacific Railway and a paved road. The town is more a city of locals and university students than a tourist destination, though Pacific Ocean beaches are a 20-minute bus or cab ride away.
Although tourism is not a primary economic engine, there is more than enough for tourists to do, volcano boarding on neighboring Cerro Negro volcano for instance. There are also hikes onto Telica when it isn’t erupting.
Climate in Nicaragua is tropical, with little seasonal temperature variation, 21 – 27° C. There are two distinct precipitation seasons, wet, May – Oct, and dry, Nov – Apr. Atlantic and Pacific hurricanes are not uncommon. Average rainfall is around 90 cm/year.
There are multiple webcams for various places in Leon. Volcano Discovery is as good a place as any to start for Telica webcams. INETER also has a page with current webcams for Nicaraguan volcanoes. One Telica camera is very close to the crater.
INETER monitors Nicaraguan volcanoes and seismicity with current observations immediately visible.
Region
The volcanic front in Nicaragua has 19 active volcanoes. The string is generally NW – SE along the Nicaraguan Depression graben. There is a 70 km break between San Cristobal and Cosiguina.
From the Telica volcano complex, Volcan Casita and San Cristobal (El Viejo) are located 16 km and 21 km NW respectively. San Cristobal is Nicaragua’s highest volcano at 1,745 m. It is a group of five volcanic edifices. It has multiple eruptions, with the most recent large eruptions a VEI 3 in Dec 2020 and Aug 2017. The complex has also suffered recent partial flank collapses and deadly lahars. The older La Pelona caldera is located at the eastern end of the complex. It appears that local activity has migrated westward over time.
The next volcanic complex some 90 km to the NW is Volcan Cosiguina. It forms a large peninsula into the Gulf of Fonseca. The volcano last erupted in 1959. It is a young stratovolcano built within an older somma. The summit caldera is about 2 km in diameter with a crater lake. A VEI 5 in 1835 was the largest eruption in Nicaragua during historic times. The VOGRIPA database lists the oldest eruption, likely the caldera forming eruption, some 62 ka, a VEI 6.6 that ejected over 27 km3 of material. There were two other eruptions in the VEI 5 range 41 and 22 ka.
The volcanic front between Telica and Momotombo is busy, with multiple volcanoes. Of these, the three most recently active are Telica, Cerro Negro and Momotombo which clearly show vegetation free flanks and new lava flows in Google Maps.
Rota (Orota) is the next neighboring volcano to Telica, located 12 km SE. It is heavily eroded with a 1 km diameter crater on top. The volcano is considered to be dormant for many centuries, though seismic swarms were recorded in 1986, 1989 and 1992. There are a pair of small domes 2 km N. The area has an extensive lava field, multiple cones, and maars.
The next volcanic complex to the SE are the Cerro Negro and Las Pilas. While Cerro Negro is only 2 km to the NW of Las Pilas, it is treated as a separate volcanic complex, the youngest volcano in Nicaragua. Cerro Negro is located 19 km SE from Telica, Las Pilas another 2 km farther to the SE.
Cerro Negro is a cinder cone and lava flow field that started erupting on the NW flank of Las Pilas in Apr 1850. The group has four young cinder cones and lava field. Eruptions have been in the VEI 2 – 3 range, with at least 25 eruptions since 1850. Seismic swarms were recorded in 2002, 2004 and 2013.
The Las Pilas volcanic complex is located generally to the SE of Cerro Negro. It is a cluster of cones around a central vent. There is a N – S fracture system cutting across the 30 km long edifice. There are numerous well-preserved flank vents and maars. There was a possible eruption in 1528 when the Spanish showed up. Other than that, the only eruptions were VEI 1 and 2 eruptions in 1952 and 1954 respectively along a fissure cutting the eastern side of the summit crater down the N flank.
The final neighboring volcano is Momotombo 39 km SE of Telica on the NW shore of Lake Managua (Lago Xolotlan). We covered Momotombo with a pair of posts in Jan and Feb 2016.
Volcano
Telica is a basaltic – andesitic volcano in the Marribios range of the Central American volcanic arc. The complex is an E – W trending series of volcanic craters, with the oldest being the La Joya pit crater at the eastern end and currently active Telica on the western one. Typical eruptive activity is primarily small, low explosive phreatic to phreatomagmatic vulcanian eruptions every few years. There have also been larger eruptions. It is considered an open vent system.
The oldest dated volcanic rocks from Telica are around 330 ka. Total volume of erupted products from the complex is estimated around 28 km3. The volcanic pile has lava flows, thick scoria layers, and pyroclastic deposits, meaning past periods of intense volcanic activity. Telica’s cone is not vegetated and has gullies on its flanks. It is topped with a 700 m wide double crater. The southern crater, source of recent eruptions, is 120 m deep.
El Liston is immediately to its SE. It has several nested craters and is more eroded.
Santa Clara is a symmetrical cone to the SE end of the complex connected to El Liston via a 400 m saddle. It is 834 m high, with a breached crater to the NW. There were Sixteenth Century eruptions reported from Santa Clara at the SW end of the group. But its crater is eroded, breached, and covered with forests throughout historical times. The reported eruptions may have come from Telica instead.
Hervideros de San Jacinto, SE of Telica is a prominent geothermal area, popular with tourists. As with most volcanoes along the Central American volcanic front, geothermal exploration is ongoing around Telica. The geothermal field is located at the eastern end of the complex.
Historical activity from Telica are low explosivity VEI 1-3 vulcanian eruptions every few years. More explosive eruptions in the VEI 2-3 range occur every few decades. The oldest historically documented eruption was a VEI 3 in 1527. The only historically documented lava flow was from a VEI 4 in 1529.
The volcano is considered to be a persistently restless volcano that has frequent eruptions, high seismicity, high fumarole temperatures and incandescence, and high volcanic gas flux. It typically has tens to hundreds of low magnitude seismic events daily even during non-eruptive periods.
The first permanent seismometer was installed half a kilometer from the active vent in 1993. It has recorded highly variable rates of seismic events. For instance, around 4,000/month were recorded 1997 – 2004. The rate varied from less than 10 events/mo to almost 20,000 events May 2004. Peaks in seismic activity do not correlate with eruptive activity. This variation in activity is thought to be a swing between stable and unstable phases, a transition between open or closed system degassing. Unstable phases have highly variable seismicity, changing spectral content of gasses, and explosive activity. Explosions take place when open-system degassing cannot be sustained.
By 2011, there were 6 broadband seismic stations, 5 short period seismic stations, ten continuous GPS stations, and one pressure sensor installed and operating on the volcano. Fumarole temperature is regularly measured. Emissions are occasionally measured, with these observations becoming more frequent in recent years.
One of the conclusions from observations of Telica over a few decades is predictability of eruptions due to the sealing and opening of the persistently active volcanic system. Sealing the shallow system seems to play a role in eruptions. This usually is seen by declines in seismicity and crater floor temperatures before the eruptive sequence begins. Persistent degassing may also trigger eruptions by opening pathways for magma.
Roman, et al in 2019 proposed three distinct states of conduit convection at Telica. The first is a stable, open state (2000 – 2010). This has stable rates of low frequency (high rate) and high frequency (low rate) seismicity, moderate gas emissions, and occasional small, isolated explosions. The second state is unstable, a sealed state that may lead to eruptions (1999, 2011, Phase 1 of 2015). This is a weak seal on the top of the convecting magma column that shows up with gradual declines in low frequency seismicity, degassing and temperature. There are also a series of weak phreatic explosions. If an eruptive phase is able to break the seal (May 2012), the system immediately returns to stable open state. If the seal is not fully opened (Phases 2 and 3 of 2015, 1982), there will be strong explosions and ash columns as high as 4 km. Rapid pressure accumulation will also produce deformation, high frequency seismic swarms, and strong phreatomagmatic explosions. Either new magma intrusion or a failed seal braking eruption could destabilize the convecting magma column.
All of this lends itself to a possible ability to forecast future activity from Telica providing seismic, deformation, gas emission, and thermal monitoring continues. Current observations, whatever they may be, must be compared to observed unrest before previous eruptions. Essentially, the Roman et al team is using calm periods from Telica to predict the severity of explosions. The longer the calm, the larger the explosion.
Eruptions
As a currently active volcano (at the time of this writing) Telica emitted ash in early Oct and early Sept 2021. Plumes were not much over a kilometer or two high, but the eruptions put the volcano into an orange (3 out of 5) activity status at the time. The Sept eruption lasted a couple hours.
Smithsonian GVP lists over 50 eruptions from Telica since the Spanish showed up in 1527. At least 7 of these took place since 2011 and another 9 2001 – 2010. The largest of its historic eruptions was a VEI 4 in 1529 and a VEI 3 in 1527. Most of the rest of them were VEI 2s or smaller. There were a LOT of VEI 2s.
The 2021 activity took place in Oct, Sept and May – Jun. These were generally small explosions and ash plumes. The plumes generally started with an explosion and continued for a time after the explosions stopped.
The following video documents Dec 2020 activity at Telica. Courtesy The Watchers Blog, Dec 2020.
2020 activity took place July – Dec with at least 7 explosions and ash plume emission eruptions. Early Dec was the most active with 775 recorded explosions 30 Nov – 3 Dec. Ash dusted communities as far away as 15 km mostly SW of the volcano.
There were a pair of eruptions in 2018, in Aug and Jun. There was a single small gas explosion in Sept 2017. 2015 – 2016 was quite active with activity starting in May 2015 and continuing through May 2016. 2015 had 7 eruptive episodes, with late May and late Sept being the most vigorous. There were 3 explosion / plume / crater incandescence episodes in Feb 2016, one in April, with the most vigorous in May 2016. The May sequence included 30 explosions, gas emission, a new vent in the crater floor, audible jetting gas, and incandescence from vents on the crater floor 11 – 12 May.
The 2015 eruptive sequence had a series of strong vulcanian explosions in three distinct phases over 6 months. There was eruption of hydrothermally altered basaltic – andesitic and hydrothermal minerals, and a small amount of juvenile unaltered ash during the middle and final phases. There were very low rates of low frequency seismicity and swarms of high frequency seismicity up to and during the eruptive period. These returned to a moderate and relatively steady rate of seismic events following the eruption. Moderate SO2 emissions during restless, non-eruptive periods were similar to non-eruptive periods in 2013 and 2016. There was a possible, poorly constrained decrease in fumarole temperature before the eruption sequence began. Ballistic blocks from these explosions were larger than those of 2011.
Sept 2012 activity included jet sounds from the crater floor, two incandescent fumaroles, and gas emissions 100 – 200 m above the crater. There were also two small explosions. The 14 – 24 May 2011 activity started with increased seismicity up to M 3.3 with explosions. Tephra fall was reported 4 km away on 14 May. Neighboring residents saw reddish colored gas plumes in the few days before the eruption. Those living on the flanks felt earthquakes. Explosions and plumes continued with the most vigorous part of the eruption taking place on 18 – 19 May with 15 explosions and a plume 2.6 km above the crater. New fumaroles opened on the N flank. Activity decreased 20 – 21 May, though there were still multiple strong explosions and plumes.
The 2011 VEI 2 eruption sequence produced vulcanian explosions, a small volume of non-juvenile, hydrothermally altered basaltic – andesitic ash. There was no deformation noted on the volcano or appreciable changes in SO2 flux from the crater. This suggests that there was no large volume of new magma migrating into the system. There were pre-eruption decreases in fumarole temperatures. The explosions and subsequent increases in fumarole temperatures, seismicity, and degassing indicate a return to open system degassing from the volcano.
Ash plumes and seismicity were observed via satellite Jan and Feb 2007.
Geothermal
One of the outstanding resources for information on volcanic systems is geothermal exploration. Telica has two fields, one of which has and active generation plant, the San Jacinto – Tizate Geothermal power plant, some 7 km E of Telica. This is a 72 MW installed geothermal power plant with production in the 65 – 70 MW range. The plant has been operating since 2013 with 13 production wells and 7 injection wells.
Image019 – Conceptual hydrothermal model of San Jacinto – Tizate geothermal field. Aquifer reservoirs and flow directions are suggested. Image courtesy Birkle & Bundschuh, Mar 2007 https://www.researchgate.net/publication/258631173_Hydrogeochemical_and_isotopic_composition_of_geothermal_fluids
Exploration in San Jacinto – Tizate began in 1953. A third of the early shallow exploratory wells in 1953 found fractured rock and steam at 60 m. These wells were uncased and abandoned. A joint feasibility study began in 1992. This included wells. Concession was awarded in 2001 with a 10 MW power plant commissioned in 2005. This was expanded in 2012 to a 72 MW plant. It has potential to support a geothermal field as large as 167 MW, a Category 1 field.
Telica – El Najo is a fumarole field on the N flank of Volcan Telica. The El Najo portion of this field has a shallow reservoir 300 – 1,000 m in the northern part of the field that sinks to 1,000 – 1,700 m in the southern portion. The deep portion is below 1,000 in the S and below 2,000 m in the N. The deep reservoir is associated with faulting zones in the eastern El Najo graben. To the best of my knowledge, Telica – El Najo has not yet been exploited. It has a potential generation capability that may be as large as 78 MW and is classified as a Category 2 field.
Tectonics
Nicaragua is located in the center of the Chortis Block, one of the major structural units forming the Caribbean Plate. Volcanism is caused by the subduction of the Cocos Plate along the Central American Trench. This subduction created the Central American Volcanic Arc along the Pacific coastline of Central America. Subduction rate along this trench is one of the fastest in the world at 8 cm/yr. Subduction angle is fairly steep at 60°.
The active volcanic arc in Nicaragua parallels the coastline, NW – SE. It is known as the Los Marribos range, within the Nicaraguan depression, a major tectonic structure that parallels the subduction trench, extending the length of western Nicaragua. The depression is defined as a half graben, limited by NW – SE striking faults.
The high angle of subduction favors the formation of multiple small intrusives, which in turn create multiple small clustered recent volcanic centers in Nicaragua. This also means that there are many potential heat sources for geothermal fields. In NW Nicaragua, the volcanic centers are so closely spaced that they form a semi-continuous range, the Marrabios Range of volcanoes extending from San Cristobal to Momotombo.
Conclusions
Telica is a persistently open restless volcanic system along the Central American volcanic front in Nicaragua. Its typical eruptions are smallish explosions. Interestingly enough over the last couple decades, its behavior is somewhat predictable, with decreases in seismicity, gas emissions, and temperature preceding explosions. The longer the period of quiet, the larger the subsequent eruption sequence. I find this remarkable, at least for a little while until it changes its behavior. Expect volcanologists to attempt to apply these conclusions to other persistently open volcanic systems.
Additional information
Eos AGU Science News – Telica volcano rested quietly right before spewing ash, A Coombs, Jul 2016
Geothermal country overview: Nicaragua, Geoenergy Marketing Services, P Hanson, Nov 2020
Geothermal activity and development in Nicaragua – producing and developing, JFR Cordero, Mar 2012
Development of a geothermal master plan for Nicaragua, Sanyal, et al, Jun 2000
Recent results from the San Jacinto – Tizate geothermal field, Nicaragua, White, et al, 2008
Geothermal exploration of El Najo field, Nicaragua, Ostapenko, et al, Jan 1997
Telica volcano rested quietly right before spewing ash, Eos, AGU, A Coombs, Jul 2016
agimarc
Spica
Granyia
volcanohotspot.wordpress.com 
Impressive study. Thank you.
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