Eruptive history Cerro Negro

1 eruptive history

1.1 eruptions of 1947, 1948 , 1950
1.2 1954 eruption
1.3 1968 eruption
1.4 1969 eruption
1.5 1992 eruption
1.6 1995 eruption
1.7 1999 eruption

eruptive history

the first recorded eruption of cerro negro occurred on april 13, 1850 , volcanic activity lasted until may 27. central vent , explosive eruptions transpired, lava flow , damage land , property. volcanic explosivity index (vei) recorded @ 2 out of 8, classifying eruption strombolian/vulcanian. finally, lava volume recorded 5.4 x 10 , tephra volume 6.5 x 10 m.

cerro negro’s second eruption took place on november 14, 1867 , volcanic activity lasted until november 30. radial fissure , explosive eruptions occurred, lava flows, along ne-sw trend line fissure. vei recorded @ 2 (strombolian/vulcanian), , tephra volume 8.6 x 10 m.

the third eruption of cerro negro occurred 32 years later , lasted november 22 november 29, 1899. explosive eruptions resulted in damaged land, , vei recorded 2. finally, tephra volume documented @ 1.7 x 10 m.

from october 28 november 3, 1914, volcano erupted explosively @ central vent. mudslides resulted in increased damage land, there no fatalities because did not flow on villages or towns. although vei yet again 2, tephra volume recorded 2.8 x 10 m.

five years later, cerro negro erupted again june 20–30, 1919, explosive eruptions resulting in vei of 2. no tephra or lava volumes recorded @ time.

just 4 years after that, october 23 until december 11, 1923, cerro negro erupted along summit , upper north flank. central vent , radial fissure explosions erupted during time, , lava flows recorded in vei 3 sub-plinian eruption. largest eruption in history of volcano, lava volume being 1.0 x 10 m , tephra volume being 3.6 x 10 m.

cerro negro erupted next on february 10, 1929, , volcanic activity lasted until march. flank (excentric) vent , radial fissures explosively erupted, resulting in excessive lava flows. volume of lava erupted recorded @ 1.0 x 10 m in vei 2 eruption.

eruptions of 1947, 1948 , 1950

eruption of cerro negro in 1948

another 18 years passed before cerro negro erupted again, on july 9, 1947 volcano had largest eruption date. vei recorded @ 3 along summit , ne flank, eruptive characteristics including central vent eruption, flank venting, , lava flows. evacuations called malpaisillo village, , major land , property damage resulted volcano’s explosive eruptions. recorded lava volume 3.8 x 10 m , recorded tephra volume 3.1 x 10 m.

less 1 year later, on march 31, 1948, cerro negro recorded strombolian eruption (vei 2) central vent. no lava or tephra volumes recorded, however. similar eruption occurred in june 1949, vei 2 eruption exploding central vent.

another sub-plinian vei 3 explosive vulcanian eruption occurred cerro negro’s central vent november 21 december 17, 1950. lava flows resulted, evacuation unnecessary. lava volume 1.0 x 10 m , tephra volume 3.8 x 10 m particular eruption.

1954 eruption

in february 1954 vei 2 strombolian eruption exploded out of cerro negro’s central vent, lava , tephra volumes not recorded. 3 years later september 4–24, 1957, vei of 2 recorded via summit , east flank of cerro negro. lava flows damaged land explosive eruption, lava volume reaching 4.5 x 10 m , tephra volume reaching 2.8 x 10 m.

the summit , south flank exploded next on september 28, 1960, , volcanic activity continued until december 26. particular vei determined level 3 after radial fissure , central vent eruptions occurred. land damage caused surrounding land via lava flows, volume of lava recorded @ 5.2 x 10 m , tephra volume recorded @ 3.4 x 10 m.

cerro negro’s ne-flank fissure erupted next on october 25, 1961. although radial fissure eruption , lava flow characteristic of particular eruption, vei recorded 1, , no lava or tephra volumes recorded. smallest cerro negro eruption date.

another eruption central vent occurred on march 21, 1962 , lasted until april. vei recorded 2, , lava flows observed, although no land damage witnessed. 1 year later, vei 1 eruption occurred central vent of cerro negro on march 21, 1963.

1968 eruption

eruption of cerro negro in 1968

the volcanic activity october 23 until december 10, 1968 marked formation of cristo rey crater, when summit , south flank of cerro negro erupted sub-plinian vei of 3. new vent formed lava flow 750m long , 600m wide , thickness of 3m. thirteen villages located near erupting volcano evacuated on 27th because of excessive ash falls. additional larger-scale evacuations nicaragua’s 2nd largest city, león, recorded ash falls of on 1 cm thick. lava flows advanced @ rate of 23 m/day, , caused additional land damage lava poured 3 of cerro negro’s craters, fountaining heights of 30m air. eruptive ash columns reached heights of 2.3 4.8 km. in addition, incandescent gases vents raised heights of 120 meters, , these seen on 50 km away volcano. when volcanic activity ceased, lava volume totaled 6.9 x 10 m , tephra volume totaled 2.7 x10 m.

1969 eruption

another small-scale vei 1 eruption took place after central vent exploded december 19–29, 1969. 2 years later february 3–14, 1971, towns surrounding cerro negro again evacuated due sudden sub-plinian vei 3 eruption of summit , formation , eruption of new eastern flank. volcanic bombs shot approximately 600m air, , incandescent gases released during time in between eruptions. ash columns approximately 10 km high, , tephra volume of 5.8 x10 m (over 300 square kilometers) caused major damage local crops , buildings. city of león alone had recorded 18 cm of ash, resulted in large-scale building collapse.

1992 eruption

over 20 years passed, , cerro negro volcano @ peace until 1 of volcano’s largest eruptions occurred on april 9, 1992. volcanic activity lasted total of 5 days, main sub-plinian eruption (vei 3) occurring on two-day time period, producing ash column 7 kilometers high. on 20,000 people evacuated, due failed water systems until eruptions ceased on 14th of april. eruption caused several fatalities, , widespread damage land , property after tephra volume measured 2.6 x 10 m. large tephra volume produced approximately 4 centimeters of ash across of león, resulting in many collapsed roofs , additional injuries , fatalities.

1995 eruption

three years later, volcanic activity started on may 29, 1995, marked beginning of first phase of eruption. small, phreatic eruptions occurred during phase, averaging 100-160 explosions per day. these strombolian eruptions generated convective ash columns reached heights of 200–1000 meters, , these explosions lasted period of 79 days. low-energy pyroclastic flow observed on northwestern flank on june 2. after june 6, number of eruptions decreased gradually @ rate of 30-40 eruptions per day. july 19, volcanic activity ceased period of 95 days. mid-november, hiatus ended , second phase commenced. eruptions continued period of thirteen days , lasted until december 3, 1995. during time, eruptions larger, , volcanic bombs , blocks 2 meters in diameter ejected cerro negro. ash columns achieve heights of 2 2.5 meters while vei measured 2, central vent explosions, pyroclastic flows, phreatic explosions, , lava dome extrusion characteristic of eruption period. new lava filled 2/3 of 1992 crater, , additional lava flows caused damage land, extending 1.5 km north of north base cone. ash falls caused damage property , farmland, average deposit of 2 millimeters per day in león (~20 km volcano), there no fatalities during safe evacuation of 6000 people in surrounding villages. overall, lava flow volume reached 8.0 x 10 m , tephra volume peaked @ 5.8 x 10 m during eruption period, resulting in addition of 50 meters of height cinder cone.

1999 eruption

the last volcanic activity @ cerro negro occurred on august 5, 1999 , lasted total of 2 days. 3 earthquakes (mw 5.2) occurred in 3 hours, triggered small-scale eruption of volcano. first time in history of cerro negro large-magnitude earthquakes preceded eruption. vei recorded 1, south flank (near cristo rey crater) experienced radial fissure eruption, along explosive , phreatic eruptions, in formation of 3 new vents. small-scale evacuations of surrounding villages carried out, low-volatile, highly crystalline basaltic magma had lava volume of 6 x 10 m. additionally, tephra volume in 106m3 range. concluded volcanic activity of cerro negro in 1999 tectonically-induced, , had 3 earthquakes not occurred, eruption have not occurred.

the recent eruptions @ cerro negro occurred in august 1999, although strong seismic activity registered in 2004. in 1998, eruption thought have occurred shortly after passage of hurricane mitch, later transpired copious amounts of steam seen rising volcano caused rainwater percolating through hot lava 1995 eruption.

following 1999 eruption, summit crater , fissures created eruption main source of volcanic gas flux today. estimated total co2 output of cerro negro conservatively estimated 2,800 t d-1.

although cerro negro volcano has been around period of 159 years, has erupted @ least 23 times, highly active compared volcanoes. historical growth of volcano has allowed documentation of growth of volcano overtime. discovered timing of future eruptions correlated volume of previous significant eruption. since there have been steady-state eruptions since 1900, cerro negro time-volume prediction model made.

although small-scale eruption did occur in 1999, larger-scale eruption expected occur in immediate future. cerro negro not differ volcanoes, in numerous hazards associated volcanic activity. these hazards include lava flows, mudslides, pyroclastic flows, , earthquakes, biggest hazard of cerro negro effects of ash , tephra fallouts.

currently, cerro negro being monitored nicaraguan seismic network, affiliated ineter (instituto nicaragüense de esdudios territoriales). these programs have total of 36 stations throughout nicaragua, , each have monitoring station on cerro negro. seismic activity, gas concentrations, surface deformation, , temperature fluctuations watched in order mitigate effects of possible eruption.

as cerro negro lies in less-populated area of nicaragua, there less volcanic risk human life compared many of other volcanoes in world. mudslides , pyroclastic flows come cerro negro not in direct path of major cities or towns. nevertheless, eruptions of cerro negro have been known cause catastrophic damage buildings , farmland, due widespread ash falls , tephra fallouts.