Seismicity associated with the landslides was recorded, although the number and size of the landslides diminished in comparison to the previous month. Deflation was recorded at the volcano. The plume drifted toward the N. Neither ash nor steam was visible on satellite imagery. Volcanic and seismic activity at Colima were at relatively low levels during June. For about a week volcanic tremor was at low levels, no explosive events were detected, and incandescent lava avalanches traveled down the volcano's S, SW, and W flanks.
No significant deformation was detected at the volcano, and SO2 emission rates and the number of avalanches decreased in comparison to the previous week. Lava was slowly emitted towards the W and SW. On 7 June, authorities lifted the preventative evacuation of communities on the volcano's SW and SE flanks.
During May, volcanic tremor, small explosions, and lava avalanches continued to occur at Colima. On 29 May infrared images revealed that 70 landslides occurred in 11 hours and there were six emissions that included incandescent material. According to the Universidad de Colima, by 3 June activity was relatively low at Colima, similar to levels observed before 10 May.
By this time activity consisted mainly of slow lava emission towards the W and SW and an average of landslides per day was reported. During the report period, incandescent lava avalanches traveled down the volcano's S, SW, and W flanks and no significant deformation was detected at the volcano. No ash was visible on satellite imagery in clear conditions. Due to the decreased level of activity, authorities considered ending the preventative evacuation of residents in towns on the volcano's SW and SE flanks, but had not done so as of 3 June.
According to the Universidad de Colima, as of 27 May strong volcanic tremor continued at Colima, and small explosions and lava avalanches occurred. Also, seismicity was recorded that was associated with landslides and degassing. Incandescent lava avalanches traveled down the SSE flank of the volcano, with sudden increases in incandescence visible for several hours. As of 24 May inflation was recorded at the volcano, but by 27 May no significant deformation was detected.
The preventative evacuation of residents in towns on the volcano's SW and SE flanks remained in affect. Colima was at Alert Level 4 5 is the highest. A strong increase in volcanic tremor at Colima caused the Scientific Committee on 18 May to evacuate hundreds of residents from several towns on the SW and SE flanks.
Scientists also recorded changes in deformation, the chemistry of spring water near the volcano, and the composition of ejected rocks. In addition, heightened temperatures were recorded on infrared imagery. On 21 May there was an increase in the number of explosive-type earthquakes and a slight decrease in tremor earthquakes in comparison to the previous day. As of 7 May volcanism continued at Colima with incandescent lava avalanches travelling down the volcano's flanks and seismicity occurring that was indicative of small explosive events and landslides.
Incandescent lava avalanches, generated from the fronts of block-lava flows, continued to travel km down Colima's S, E, and W flanks and m down the SW flank. As of 29 April volcanism continued at Colima with incandescent lava avalanches travelling down the volcano's flanks and seismicity occurring that was indicative of small explosive events and landslides. As of 6 April volcanism continued at Colima and more small explosion earthquakes were recorded than during the previous week.
Incandescent lava avalanches, generated from the fronts of block-lava flows, continued to travel km down Colima's S, SW, and W flanks, and sporadically down the E flank. In addition, block-lava flows extended m down the SW flank and 2 km down the W flank. Universidad de Colima reported that as of 23 March volcanism continued at Colima and more small explosion earthquakes were recorded than during the previous week.
Incandescent lava avalanches, generated from the fronts of block-lava flows, continued to travel km down Colima's S, SW, and W flanks, and also sporadically traveled down the volcano's E flank. Block-lava flows extended m down the SW flank and 2 km down the W flank.
During March, avalanches of incandescent volcanic material continued to flow km down Colima's S, SW, and W flanks. Most activity occurred on the S and W flanks, while activity slightly diminished on the SW flank. Block-lava flows extended m down the SW flank and had an estimated volume of , m3. Block-lava flows reached a distance of 2 km down the W flank, and sporadic avalanches occurred on the E flank.
As of 6 March activity at Colima was similar to the previous weeks. Avalanches of incandescent material continued to travel km down the volcano's S, SW, and W flanks. Block lava continued to flow down the SW flank of the volcano, extending as far as m from the summit.
Lava was also visible travelling as far as 2 km down the volcano's W flank, and down the E flank. The emission was too small to be visible on satellite imagery. During 27 February- 2 March volcanism at Colima was similar to the previous week. Avalanches of incandescent material continued to travel down the volcano's S, SW, and W flanks. They extended km from the volcano's summit and were recorded seismically. By 28 February the flow was 15 m high, 55 m wide, and had a volume of about , m3.
Lava was also visible flowing as far as 2 km down the volcano's W flank, and down the E flank. During February, avalanches of incandescent material continued to travel down the S, SW, and W flanks of Colima. They extended km from the volcano's summit and were recorded in seismic data. Lava continued to flow down the SW flank of the volcano, extending as far as m from the summit.
Lava was also visible flowing down the volcano's W flank as far as 2 km from the summit. Avalanches are expected to occur from the lava-flow front travelling down the volcano's E flank. About metric tons of SO2 were measured per day, which was lower than values measured in when the current eruptive episode began.
During February, seismicity was relatively low at Colima and was dominated by landslide signals. In addition, landslides continued to travel down the volcano's S, SW, and W flanks, extending up to km from the volcano's summit. During February incandescent rockfalls continued to travel down Colima's S flank extending up to 2 km from the summit.
In addition, very low magnitude earthquakes continued. Scientific Advisory Committee of Colima University personnel and the authorities of Colima State determined that the continuous inflation and numerous small earthquakes that have been recorded during the past 2 weeks could lead to the formation of lava flows and pyroclastic flows. On 5 February La Yerbabuena, the nearest village to the volcano 8 km away , was evacuated.
According to news reports, on 6 February University of Colima staff flew over Colima and observed lava flows travelling down the volcano's S flank. On 9 February two pyroclastic flows occurred.
The Universidad de Colima reported on 30 January that the growing lava dome at Colima could result in either a dome collapse in days or weeks that would send pyroclastic flows down the volcano's S flank, or explosions could destroy the lava dome and hurl volcanic fragments several kilometers. Several incandescent landslides were seen traveling less than 1 km down the S and SSW flanks of the volcano. During a flight over the volcano, members of the Advisory Scientific Committee noticed that dome growth occurred towards the W.
Seismicity was relatively low; numerous earthquakes with very low magnitudes occurred. Residents were advised to be ready in case an increase in activity leads to the evacuation of towns around the volcano. Photographs of Colima taken on 13 January revealed that a new lava dome grew in the volcano's crater.
The dome was approximately m in diameter at the base and 46 m high. No ash was visible in satellite imagery from either eruption. A flight over Colima on 5 December revealed that the spine on the lava dome, first observed on 31 October, was no longer visible.
Photographs of Colima taken on 3 November revealed that a spine had grown on the May lava dome. The light-colored spine was about 40 m tall, 40 meters wide at its base, and smooth with vertical walls. During early November seismicity was low, with about 10 earthquakes occurring per day. As of 7 November, significant changes in deformation were recorded. The Universidad de Colima reported on 4 November that significant deformation had been registered at Colima. Seismicity remained low and there was little visibility at the volcano.
During an excursion to Colima on 17 March by personnel from the Universidad de Colima a new crater was observed that was assumed to have been formed during the 22 February eruption.
They also noted that fumarolic activity was stronger in May than in March and fumaroles were active around the new dome mainly to the N, NE, and E. The new lava dome was the first evidence of effusive volcanic activity since the November February effusive episode. The Volcanological Observatory of Colima University reported that a moderate explosion occurred at on 22 February.
The collapse of the eruptive column generated small pyroclastic flows that traveled towards the SW. According to the observatory, the events were not sufficient to trigger an expansion of the zone of exclusion around the volcano, which remained at 6. The Volcanological Observatory of Colima University reported that during the week seismicity was at an average level and deformation was low.
A small seismic swarm occurred during on 16 November. The Volcanological Observatory of Colima University reported that small exhalations occurred at Colima at on 8 November, on 9 November, and at on 10 November. According to the observatory, the events did not exceed the established safety limits so the zone of exclusion remained at 6. Click on the index link or scroll down to read the reports.
On 1 December , the volcano began erupting. The summit crater was filled with viscous lava, and two flows descended the E flanks. There were hot avalanches, and eruptions were frequently visible at night from locations 20 km away. Information Contacts: S. By the end of December the E lava flow had descended the flank of the cone, reaching the vegetation and a ravine at the base. The flow advanced about 2, m in 60 days.
On 28 January two new lava flows started to develop at the S and W sides of the dome [but see ]. The eruption decreased during February and presumably March. The lava flows that were thought to be developing on the W side of the dome in late January did not develop at all.
Other activity has almost stopped. De la Cruz last visited the volcano about 1 March Servando De la Cruz has not visited the volcano recently, but reports that he has received indicate that activity has almost completely ceased.
Servando De la Cruz did not visit the volcano in mid-May since the activity had already ceased. An observer located near the volcano will report any new activity directly to him. The following information is from visits to Colima during December January , December , and February by James Luhr and others. Since the extrusion of more than 10 8 m 3 of andesitic block lava between November and June , activity has consisted of numerous brief ejections of ash and incandescent material, and several episodes of lava dome growth, all in the E part of the summit crater.
When Luhr and others returned in December , this dome had disappeared and the E part of the crater had a relatively flat floor, only about 2 m below the crater rim, containing numerous explosion vents m in diameter. By February , a new lava dome had been extruded into the E part of the summit crater. The geologists interpreted the dome's smooth reddish SE flank in the direction of the principal lava flows as more likely to have been caused by slumping than by tephra accumulation.
The remainder of the dome was composed of block lava. No information is presently available on post-February activity. Information Contacts: J. Luhr , Univ. Colima began to erupt during the first week of December. Very viscous lava emerged from two vents in the dome that has covered the summit crater since the late 's.
Aerial observations revealed that lava extruded from a vent in the E half of the dome flowed down its S flank. Less voluminous lava extrusion occurred from a vent in the W half of the dome. Activity was continuing as of 20 January. No felt earthquakes have been reported, nor were volcanic earthquakes detected during 4 days of monitoring with four portable seismographs near Colima. However, small tremors of unspecified origin were detected. The present eruption is similar to that of November June The most recent dome growth occurred between visits by geologists in December and February De la Cruz Reyna and F.
Medina , UNAM. The volcano had an apparently active block lava flow descending from the summit down the S flank for several hundred meters. Below this level was active scree. The flow was gray, contrasting with the various browns of the earlier lava units. Heat waves emanated from the flow and rockfalls were rare, indicating a slow extrusion rate. The volcano had a significant gaseous plume that was sampled and measured by the RAVE Electra aircraft with a complete battery of atmospheric sampling gear.
During the sampling, one short second burst of gaseous emission occurred, in which the emission rate approximately doubled. Further Reference. Casadevall, T. D6, p. Information Contacts: W. Rose, Jr. Zoller , Univ. The following report from James Luhr supplements the report from Mexican scientists in Geologists from the Univ.
On 20 January, the flow had a simple tongue shape and was some m long. By 3 March, the lava had reached 1 km length. Block-and-ash flows were common from the uppermost margins of the lobe with surprisingly few from the flow front. In several instances, sizeable 2, m 2? This may be a major process of downslope movement of the flow. The active scree deposit below the lava contained blocks several meters in diameter, grading into a new sand and conglomerate wedge flooding the upper reaches of the Barranca Playa de Montegrande.
The latest lava continues this trend. A French team reached the N rim of the summit cone in early December. Storm damage to trails prevented them from reaching the S side of the cone, so they were unable to see the S flank lava flow produced by the eruption that began in December Only fumarolic activity was observed in the W part of the crater and on the N flank.
Rockfalls occurred several times per day from the front of this flow and it may still have been advancing very slowly. James Luhr and others visited Colima in mid-January and again in early February. The S flank lava flow appeared to have advanced very little since last observed by Luhr in March Residents of the area reported that incandescence had ended in June Plume emission continued in early at about the same intensity as a year earlier, but there were no episodic increases in intensity of plume emission as there had been in early Vapor emission from fumarole field; SO 2 flux estimated.
Most of the plume came from the fumarole field on the NW side of the summit lava field. Information Contacts: R. Stoiber , L. Benton , C. Connor , D. Douglass , D. Shumway , and J. Swarts , Dartmouth College. Large linear fractures had opened on the NE flank of the volcano between the summit and Volcancito Cone, at an elevation of approximately 3, m figure 1.
New arcuate fractures of comparable size are concave downslope and head across the linear fractures. Fracturing and fumarolic activity persisted at higher elevations, but was concentrated below the summit. Hundreds of tremors were felt during a bivouac near the fumarole field on the night of 26 November. A small fissure was observed cutting across the summit of Volcancito roughly in line with those found at higher elevations. This is a marked change in activity since our group last visited Colima in April , when fractures and fumarolic activity were not observed in this area.
Information Contacts: C. Connor , B. Gemmell , and R. Stoiber , Dartmouth College. The following is from Claude Robin and John Murray. According to the inhabitants of San Marcos 14 km SE of the summit , a red summit glow was seen at night in early January for the first time since , together with glowing 'sparks'.
At the same time people at Colima town 30 km S of the summit observed a dark ash plume during the day, instead of the usual white condensation plume. Earthquakes were felt at San Marcos during this period. An 8-km levelling profile set up by Murray in December was reoccupied and extended to 10 km. This result was confirmed by three dry tilt stations 1.
The fractures seen by Dartmouth College geologists in late November figure 2, number 1 were still the site of fumarolic activity, at an altitude of 3, m all altitudes by altimeter , but the fumarole on Volcancito had ceased to be active. The northern slope had shallow N-S fractures m across figure 2, number 2 with sublimate deposits, but no active fumaroles.
These fractures were cut by others figure 2, number 3 trending towards Volcancito approximately NE. A major N-S zone of weakness, m across and very deep with strong fumarolic activity, divided the summit plateau in two figure 2, number 4. The high temperature was found inside a shallow m pit on the SW edge of the summit plateau figure 2, number 5 perhaps an explosion pit formed in January.
A red glow was detectable inside fumaroles even in bright daylight and socks were singed. Thirty to 40 m below the summit to the W and NW are the remains of the old crater rim figure 2, number 8 with a flatter shelf containing scattered fumaroles on its inside edge figure 2, number 7.
On photos taken from the air, two fractures trending NE figure 2, number 9 are visible crossing the flows SE of the summit, but without noticeable fumarolic activity. This may have provoked some depressurization of the near-surface magma, increasing surface temperatures and fumarolic activity, and culminating in the minor ash eruptions of early January.
The levelling and dry-tilt data suggest no buildup of magmatic pressure, and the decline in seismic activity since November also indicates that for the moment, there are no portents of a larger eruption such as those that followed the earthquakes of and Murray , Wheathampstead, UK. On 29 November, geologists observed the volcano from Nevado de Colima, an eroded cone 5 km to the N. A very small plume was emerging from the summit.
Stoiber , C. Connor , and other geologists, Dartmouth College. The Univ of Colima 37 km S of the volcano reported that a sulfur smell and increased fumarolic activity were noticeable on 2 March and twice during the next few weeks. A sulfur smell had not been reported for at least 10 years. On 2 July at about a large Merapi-type avalanche occurred from the S and SE base of the summit lava dome. Avalanche debris probably reached the base of the summit cone, but there were no reports that it continued into vegetated areas downslope.
Residents of the area reported that the activity generated a cloud, but geologists could not confirm whether it was produced by a phreatic explosion or was fine-grained debris from the avalanche.
A relatively large talus pile that had accumulated at the S and SE base of the dome was no longer present after the avalanche.
Poor weather conditions prevented geologists from reaching the summit. No increase in seismicity was observed on a permanent seismograph 30 km S of the volcano.
S and P arrivals were only about 1 second apart, indicating a nearby source. No B-type events or tremor were recorded. Emissions were dense, light-gray, and toxic. Large rockfall avalanches similar to the one that originated at the base of Colima's lava dome on 2 July have been occurring periodically. Thick sulfur deposits coated the areas around fumaroles and avalanche source areas. Contrary to some public reports, rumbling noises were not heard during the visit.
Information Contacts: G. Castellanos , R. Ornelas , J. Reyes , and H. On 2 July , residents of the S side of Colima observed a mushroom cloud , m high emerge from the central dome, accompanied by a loud explosion. Tons of volcanic material fell on the SE side of the cone. Municipal authorities requested assistance, and a group of security personnel and two geologists from Guadalajara were sent to investigate.
Their report described the activity as a "phreatic explosion from the central dome and an avalanche The same two geologists and another from the National Univ climbed the volcano on 20 April The dome, m in diameter, had a large depression m diameter, 50 m deep [but see ] on its SE side.
Only fragmented older rocks were found on the dome and in the avalanche; there was no evidence of fresh glass. Weekly reports are sent to the Geography Department at the Univ of Guadalajara, km N of the volcano. Geologists from the Univ visit the volcano every two months if weather permits. Flores, J. Information Contacts: Julian A.
While working on a hazard map during October and November, geologists A. Suarez Plascencia, R. Uribe, A. Soler, and G. Stoopes observed that a section of the E part of the dome had caved in since their last visit at the end of January. A fumarole that had been seen since was not active in January, but its activity had resumed at an increased level by October and November, and there were two new vents that emitted vapor.
On 13 November, the geologists noted three new bombs 1-, 3-, and 4-m-diameters that had been ejected from the summit dome since January and fallen on the top of Volcancito, a parasitic cone 1 km NE of the summit. The bombs were porphyritic andesite with plagioclase, hornblende, and pyroxene phenocrysts of up to 5 mm.
Univ of Guadalajara geologists climbed the volcano later in November and noted new fumarolic activity that had not been evident in April.
From a highway km E of the volcano on 22 December, Arizona State Univ geologists saw small explosions from the summit dome, producing puffs of steam and darker ash clouds, typical of recent activity at the volcano. The summit crater, m in diameter, was filled with irregular blocks.
On the N side of the summit area, a dome m in diameter rose m above the crater rim; the SW-W side was occupied by a platform with an irregular surface; and a depression m in diameter extended m below the lowest point on the crater's SE rim.
Vapor emission was brownish; the dark plume color has at times misled distant observers who have reported eruptions. The fumaroles were relatively dispersed, with gases emerging between blocks, depositing red, orange, yellow, and white sublimates. The depression formed 2 July after a phreatic explosion and avalanche was deeper than during the previous visit to the summit in The area was warm, but no fumarolic activity was occurring.
Samples from the bottom of the depression were collected for analysis. The remainder of the summit area was an irregular blocky surface with some small dispersed fumaroles. Winds that blow from the coast were eroding the SW flank, causing scoria and sand-sized debris to flow downslope. Fumaroles were concentrated in three areas on the dome figure 4.
On 14 May, gas emission, dominated by SO 2 , had increased and the gas was light-brown in color, but it had substantially diminished by May. The depression that formed 2 July [] after a phreatic explosion and avalanche from the summit was in diameter and m deep from the high point in the middle of the summit area [but see ]. The area was warm but fumaroles observed during a November overflight had disappeared.
Altered fragmented rocks and sand were present on the depression's floor. The remainder of the summit area, an irregular platform, was composed of blocks of many shapes and sizes. Warm gases containing SO 2 were emitted, and blocks were altered and covered with sulfur. On the SW flank, a talus slope of scoria and sand had developed. Thermometric equipment was not available to the team. Emissions were dense, dark-gray in color, and had a pH of Sheridan, M. Skip to main content. Toggle menu Go to search page.
Search Field. You are here Home. Close-up of dome The mountain remained dormant for forty-four years before it once again became active. Left: Eastern slope of Fuego. Right: summit crater. Taylor, S. Thorpe, R. Tectonophysics 40 , 19—26 Ulmer, G. Wager, L. Walker, D. Union, PNW Meeting, abstr. Waitz, P. In: Mem. Cient Antonio Alzate, ed. Wells, P. Weyl, R. White, S. Syracuse University, Unpublished Ph. Wilcox, R. Williams, H. Williams, R.
Wood, B. Woodruff, L. Wright, T. Yanugi, T. Download references. You can also search for this author in PubMed Google Scholar. Reprints and Permissions. The Colima Volcanic complex, Mexico. Download citation. Received : 05 September Accepted : 01 November Issue Date : March Anyone you share the following link with will be able to read this content:.
Sorry, a shareable link is not currently available for this article. Provided by the Springer Nature SharedIt content-sharing initiative. Skip to main content. Search SpringerLink Search. References Allen, J. Fomento, Google Scholar Barker, D. Acta 40 , — Google Scholar Dungan, M.
Acta 29 , — Google Scholar Garcia, M. Petrol, in press, Green, T. Submitted for publication Lofgren, G. Mexico 61 , 77—92 Google Scholar Luhr, J. Nature , — Google Scholar Mooser, F. Archaeometry 11 , 21—52 Google Scholar Pichler, H. Tectonophysics 55 , 35—61 Google Scholar Rittmann, A. Stuttgart: Sartorius, C. Tectonophysics 40 , 19—26 Google Scholar Thorpe, R. This latest eruptive phase has not ended, meaning the situation with Colima today resembles the pattern of previous large eruptions in and In recent years, the population that lives near the Colima volcano has grown exponentially due to the economic growth in Colima and Jalisco states.
In its vicinity, there are at least 28 villages and cities crossing both states. Geodetic monitoring, sometimes called volcanic deformation , uses dry inclinometers installed at the volcano and periodic measurement of geodetic benchmarks using an electronic distance-meter to predict future eruptive behaviour.
After a quiet period between August and March , Popo started to explosively erupt again in early March and, later that month, the first lava domes were observed inside the immense crater of the volcano. At the time, the crater was almost kilometre in diameter and almost to metres deep. Since , Popo has continued to experience explosive events that have wiped away the lava domes formed inside the crater.
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