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Cayambe

Photo of this volcano
  • Country
  • Volcanic Region
  • Landform | Volc Type
  • Last Known Eruption
  • 0.029°N
  • 77.986°W

  • 5,790 m
    18,996 ft

  • 352006
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

Most Recent Weekly Report: 28 December-3 January 2017 Citation IconCite this Report

On 28 December IG reported continued anomalous seismic activity at Cayambe characterized by volcano-tectonic and long-period earthquakes located 2-8 km below the summit. As many as 40 earthquakes had been recorded each day for the previous two weeks and starting on 24 December that number again increased, especially for volcano-tectonic events. A swarm on 27 December consisted of 100 small-magnitude events. A strong sulfur odor persisted, and cracks in the glacier near the summit that climbers has recently reported were visible during an overflight. In addition, deformation on the flanks was detected in GPS data.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


Most Recent Bulletin Report: November 2006 (BGVN 31:11) Citation IconCite this Report

Seismic swarms occur erratically in 2004 and 2005

During 2004, Cayambe's seismicity increased three times, on 25-31 January, on 25 February-5 March, and on 4-12 October. Our previous report on Cayambe discussed events through November 2003 (BGVN 28:11).

The first seismic swarm began on 25 January 2004 when the number of volcano-tectonic (VT) earthquakes increased, with seismic activity occurring in bands lasting 2-3 hours. The events were small in magnitude and were located ~ 1-4 km below the SW flank. At 1934 on 27 January, a magnitude 3.4 earthquake was recorded. On 29 January, the activity peaked with 148 earthquakes reported. Seismicity thereafter decreased to normal base-line levels.

The second earthquake swarm began on 25 February with an increased number of VT earthquakes. Like the January events, these earthquakes were of low magnitude. The largest event occurred on 29 February at 1059 measuring M 3.1. The events were localized primarily below the E flank with peak activity on 2 March, when 271 earthquakes were registered. The energy released by this cluster was far larger than the one in January and was almost comparable to activity in March 2003 (figure 2).

Figure (see Caption) Figure 2. The total number of earthquakes each day at Cayambe during 28 December 2002 through early January 2004. The spike in daily earthquakes seen during late March 2003 (up to 330 per day) was discussed in BGVN 28:11. A spike about half that size occurred in late January 2004. Courtesy of the Instituto Geofisico.

On 12 March, a small increase in activity was recorded, and on the morning of 15 March, a M 3.6 earthquake was recorded on the S flank. Residents reported no felt earthquakes.

On 4 October, there was a slight increase in the number of events registered with a total of 18 events, 17 of which were hybrid events. At 2333 on 6 October a M 3.4 event was recorded. These earthquakes were located in the S zone of the volcano edifice. Two seismic swarms on 8 October consisted of 177 VT earthquakes. The first swarm registered at 0500 and lasted an hour. The second swarm began at 1130 and lasted approximately 9 hours. Some of these events were located in the SW flank. After the seismic anomalies on 4 and 6- 8 October, activity returned to normal base-line levels.

Apart from the swarms between September and October, the seismicity appears to have changed, with the number of VT events diminishing by one-half in relation to those previously recorded, whereas the number of hybrid events tripled. Later, long-period LP events were again observed, which is characteristic of this volcano returning to normal levels.

The internal seismic activity at Cayambe is characterized by the generation of 10 events per day on average. Nevertheless, this type of activity has alternated with sporadic seismic swarms consisting of hundreds of events lasting several days, after which activity returns to the base-line level. These types of seismic swarms were recorded in December 2002, March 2003, and in January, March, and October of 2004 (figure 3), with similar characteristics and averaging 2 days in duration. Scientists inferred the cause of the observed seismicity as related to motion of fluids in the interior of the edifice. Thermal images obtained during 2004 did not contain anomalies.

Figure (see Caption) Figure 3. The total number of earthquakes each day at Cayambe during 2004 (tick marks along x-axis are every 14 days). The record was punctuated by three strong increases in seismicity, during late January, during February-March, and during October. The spike in daily earthquakes seen during February 2004 neared 300 earthquakes per day. Courtesy of the Instituto Geofisico.

During 16-18 September 2005 a short seismic episode occurred with earthquakes on the SW flank, ranging from 135 to 330 events per day. The earthquakes reached a maximum magnitude of 3.6.

Information Contacts: Instituto Geofisico (IG), Escuela Politécnica Nacional, Apartado 17-01-2759, Quito, Ecuador (URL: http://www.igepn.edu.ec/).

Weekly Reports - Index


2016: December
2005: September
2004: February
2003: November


28 December-3 January 2017 Citation IconCite this Report

On 28 December IG reported continued anomalous seismic activity at Cayambe characterized by volcano-tectonic and long-period earthquakes located 2-8 km below the summit. As many as 40 earthquakes had been recorded each day for the previous two weeks and starting on 24 December that number again increased, especially for volcano-tectonic events. A swarm on 27 December consisted of 100 small-magnitude events. A strong sulfur odor persisted, and cracks in the glacier near the summit that climbers has recently reported were visible during an overflight. In addition, deformation on the flanks was detected in GPS data.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


14 December-20 December 2016 Citation IconCite this Report

IG reported that a seismic swarm detected at Cayambe on 5 June was characterized by an increase in the number of volcano-tectonic events. The swarm occurred near an active fault system, NE of the volcano. The seismic activity progressively declined to baseline levels during August. A minor increase was again observed in September, with events migrating to locations underneath the volcano, and then became more pronounced in November. Anomalously large-magnitude earthquakes occurred on 14 November (M 3.3) and on 27 November (M 3.6). Another swarm was also detected on 27 November. Seismicity continued above baseline levels through 2 December. In addition, climbers reported an increase in a sulfur odor.

On 13 December IG noted that during the previous week there was an average of 68 earthquakes/day, mainly volcano-tectonic events and some long-period signals. A M3 event located at a depth of 7 km below the summit was recorded on 8 December. Climbers continued to report an increase in a sulfur odor, and also the presence of new cracks in the glacier near the summit.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


28 September-4 October 2005 Citation IconCite this Report

A cluster of earthquakes that had been recorded at Cayambe since 16 September, with about 300 small earthquakes occurring during 16-18 September, decreased in number significantly after 19 September. During 19-25 September, an average of 5.3 earthquakes occurred daily.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


14 September-20 September 2005 Citation IconCite this Report

During 16-18 September, a cluster of 330 small earthquakes occurred at Cayambe. The earthquakes reached a maximum magnitude of 3.6. They occurred on the volcano's SW flank, where previous clusters had been located. The cluster had not reached the level of one that took place in March of 2004. IG reported that these types of clusters occur fairly regularly at Cayambe and could be related to changes in the internal pressure of the volcano. The earthquakes continued through at least 19 September.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


18 February-24 February 2004 Citation IconCite this Report

On 29 January a swarm of ~148 small volcano-tectonic earthquakes occurred at Cayambe. By 1 February seismicity had decreased, reaching "normal" base levels. IG reported that the swarm may have represented an increase in the internal pressure of the volcano due to the arrival of fluid, possibly magma.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


12 November-18 November 2003 Citation IconCite this Report

During 3-9 November, about nine earthquakes occurred per day at Cayambe, near the daily average since August 2003 and about twice the daily average of 4 per day before that. Seismicity also included small clusters of tectonic earthquakes with magnitudes less than 3. There were reports of a strong scent of sulfur in the sector of Picos Jarrína at an elevation of ~5,460 m. The scent was strongest near cracks.

Source: Instituto Geofísico-Escuela Politécnica Nacional (IG-EPN)


Bulletin Reports - Index

Reports are organized chronologically and indexed below by Month/Year (Publication Volume:Number), and include a one-line summary. Click on the index link or scroll down to read the reports.

11/2003 (BGVN 28:11) Some anomalous 2003 seismicity

11/2006 (BGVN 31:11) Seismic swarms occur erratically in 2004 and 2005




Information is preliminary and subject to change. All times are local (unless otherwise noted)


November 2003 (BGVN 28:11) Citation IconCite this Report

Some anomalous 2003 seismicity

This report largely discusses seismicity at Cayambe during January-October 2003 (figure 1). On the whole, the numbers of daily earthquakes remained fairly constant at low to moderate levels (typically fewer than 25 earthquakes per day). On six days the number of daily earthquakes approached 50 or greater (1 January, 15, 28, 29, and 30 March, and 1 April). Epicenters were concentrated on the SW flank, similar to the pattern in December 2002. During the year, residents did not report feeling earthquakes at Cayambe, but did notice sulfurous odors. Although some seismic signals had an uncertain origin, others were interpreted as related to magma movement.

Figure (see Caption) Figure 1. The total number of earthquakes each day at Cayambe between 1 January and 27 October 2003. Courtesy of the Instituto Geofisico-Escuela Politecnica Nacional, Ecuador.

Observers saw no changes at Cayambe during January, although strong sulfurous odors were reported early in the month. Very low seismicity prevailed, with an average of five earthquakes per day during the second week in January. In general, the earthquakes registered since 2 January 2003 were long-period earthquakes; a few hybrid events and fracture events also were recorded. Some small volcano-tectonic (VT) earthquakes registered. On 31 January, following a week of low to moderate seismicity, two larger earthquakes were recorded: the first under the volcano, M 3.9; the second to the E, M 3.5. Neither earthquake was felt by area residents. Associated, small long-period (LP) earthquakes also registered, although the late-January daily totals were still low to modest. Following this activity, seismicity dropped and generally remained low through February and early March.

On 8 March an M 3.6 earthquake triggered about 2 hours of small VT earthquakes beneath Cayambe's S flanks. Seismicity again dropped to low levels until 14 March when there was a small cluster of shallow VT earthquakes lasting about 1 hour. These events were under M 2, and afterwards seismicity dropped to background levels.

The high for the year occurred during 24-30 March when earthquakes peaked at approximately 335 per day. Clusters of events were noted. Those on 27 March included an M 3.9 earthquake, and those on 29 March included two M 3.6 earthquakes. The events were located at 5-6 km depth below the SW flank. This was the same area in which seismic clusters occurred during December 2002. There were 99 earthquakes counted on 31 March. None larger than M 3, they consisted of up to 95 VT and four hybrid events.

In early April seismicity again dropped to low levels, increasing slightly in the second week of the month. The recorded LP and hybrid events registered were thought likely related to fluid movement inside cracks. Small VT earthquakes were recorded on 13 April; otherwise, seismicity remained low through the rest of the month. The smell of sulfur was noticed during a 14-20 April visit, but no other changes were noted. Seismicity remained low throughout May, with only occasional VT, LP, and hybrid events.

Seismicity increased slightly in early June, but still remained close to background levels. A new signal appeared at the Refugio station, characterized by high frequency at the beginning and a very long coda (tail). Thereafter, activity dropped and remained low for the rest of June.

A series of VT earthquakes occurred during the first week of July; the maximum activity was on 1 July, with 16 events. Nevertheless seismicity remained near background levels, and stayed low until early August. A VT earthquake occurred on 4 August beneath the W flank; on 6 August seismicity increased slightly and was characterized by hybrid events. Activity was low through mid-August. A series of VT events related to rock fracturing occurred between 18 and 31 August; the majority occurred on 22 and 25 August, with events reaching M 3.5. These events beneath the SW flank were similar to the spike in activity in March. Activity dropped again during the following month.

For the last week of September, seismicity was still at background levels. A single VT event registered, with a magnitude of 3.2, located beneath the volcano at a depth of 4 km. As with the previous cases, the event was too small to be felt by area residents. Between 13 and 19 October, seismicity generally remained normal, but on 15 October, a small cluster of VT earthquakes occurred S of the crater. On 23 October another small cluster of VT earthquakes (M <3) was recorded beneath the SE flank, in a part of the same zone as the events of the previous week.

Over these weeks the base seismicity level seemed to increase slightly (figure 1). During 3-9 November, about nine earthquakes occurred per day, near the daily average since August 2003 and about twice the daily average of 4/day before that. Seismicity also included small clusters of tectonic earthquakes with magnitudes less than 3. There were reports of a strong scent of sulfur in the vicinity of Picos Jarrína at an elevation of about 5,460 m. The scent was strongest near cracks.

Information Contacts: Geophysical Institute (IG), Escuela Politécnica Nacional, Apartado 17-01-2759, Quito, Ecuador (URL: http://www.igepn.edu.ec/).


November 2006 (BGVN 31:11) Citation IconCite this Report

Seismic swarms occur erratically in 2004 and 2005

During 2004, Cayambe's seismicity increased three times, on 25-31 January, on 25 February-5 March, and on 4-12 October. Our previous report on Cayambe discussed events through November 2003 (BGVN 28:11).

The first seismic swarm began on 25 January 2004 when the number of volcano-tectonic (VT) earthquakes increased, with seismic activity occurring in bands lasting 2-3 hours. The events were small in magnitude and were located ~ 1-4 km below the SW flank. At 1934 on 27 January, a magnitude 3.4 earthquake was recorded. On 29 January, the activity peaked with 148 earthquakes reported. Seismicity thereafter decreased to normal base-line levels.

The second earthquake swarm began on 25 February with an increased number of VT earthquakes. Like the January events, these earthquakes were of low magnitude. The largest event occurred on 29 February at 1059 measuring M 3.1. The events were localized primarily below the E flank with peak activity on 2 March, when 271 earthquakes were registered. The energy released by this cluster was far larger than the one in January and was almost comparable to activity in March 2003 (figure 2).

Figure (see Caption) Figure 2. The total number of earthquakes each day at Cayambe during 28 December 2002 through early January 2004. The spike in daily earthquakes seen during late March 2003 (up to 330 per day) was discussed in BGVN 28:11. A spike about half that size occurred in late January 2004. Courtesy of the Instituto Geofisico.

On 12 March, a small increase in activity was recorded, and on the morning of 15 March, a M 3.6 earthquake was recorded on the S flank. Residents reported no felt earthquakes.

On 4 October, there was a slight increase in the number of events registered with a total of 18 events, 17 of which were hybrid events. At 2333 on 6 October a M 3.4 event was recorded. These earthquakes were located in the S zone of the volcano edifice. Two seismic swarms on 8 October consisted of 177 VT earthquakes. The first swarm registered at 0500 and lasted an hour. The second swarm began at 1130 and lasted approximately 9 hours. Some of these events were located in the SW flank. After the seismic anomalies on 4 and 6- 8 October, activity returned to normal base-line levels.

Apart from the swarms between September and October, the seismicity appears to have changed, with the number of VT events diminishing by one-half in relation to those previously recorded, whereas the number of hybrid events tripled. Later, long-period LP events were again observed, which is characteristic of this volcano returning to normal levels.

The internal seismic activity at Cayambe is characterized by the generation of 10 events per day on average. Nevertheless, this type of activity has alternated with sporadic seismic swarms consisting of hundreds of events lasting several days, after which activity returns to the base-line level. These types of seismic swarms were recorded in December 2002, March 2003, and in January, March, and October of 2004 (figure 3), with similar characteristics and averaging 2 days in duration. Scientists inferred the cause of the observed seismicity as related to motion of fluids in the interior of the edifice. Thermal images obtained during 2004 did not contain anomalies.

Figure (see Caption) Figure 3. The total number of earthquakes each day at Cayambe during 2004 (tick marks along x-axis are every 14 days). The record was punctuated by three strong increases in seismicity, during late January, during February-March, and during October. The spike in daily earthquakes seen during February 2004 neared 300 earthquakes per day. Courtesy of the Instituto Geofisico.

During 16-18 September 2005 a short seismic episode occurred with earthquakes on the SW flank, ranging from 135 to 330 events per day. The earthquakes reached a maximum magnitude of 3.6.

Information Contacts: Instituto Geofisico (IG), Escuela Politécnica Nacional, Apartado 17-01-2759, Quito, Ecuador (URL: http://www.igepn.edu.ec/).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.

Eruptive History

There is data available for 22 confirmed Holocene eruptive periods.

1785 Feb - 1786 Mar Confirmed Eruption VEI: 2 (?)

Episode 1 | Eruption Upper SE flank
1785 Feb - 1786 Mar Evidence from Observations: Reported

List of 5 Events for Episode 1 at Upper SE flank

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Lava flow Uncertain
   - - - -    - - - - Ash
   - - - -    - - - - Lahar or Mudflow Uncertain
1785 Feb    - - - - VEI (Explosivity Index)

1700 (?) Confirmed Eruption  

Episode 1 | Eruption
1700 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1590 (?) Confirmed Eruption  

Episode 1 | Eruption North flank of main summit
1590 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 5 Events for Episode 1 at North flank of main summit

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
   - - - -    - - - - Blocks

1570 (?) Confirmed Eruption VEI: 4

Episode 1 | Eruption North flank of main summit
1570 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 7 Events for Episode 1 at North flank of main summit

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Ash
   - - - -    - - - - Bombs
   - - - -    - - - - Blocks
1570
(?)
   - - - - VEI (Explosivity Index)

1440 (?) Confirmed Eruption  

Episode 1 | Eruption
1440 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1290 (?) Confirmed Eruption VEI: 4

Episode 1 | Eruption Tarugo Corral lava dome (NE flank)
1290 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 7 Events for Episode 1 at Tarugo Corral lava dome (NE flank)

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Ash
   - - - -    - - - - Blocks
   - - - -    - - - - Lahar or Mudflow
1290
(?)
   - - - - VEI (Explosivity Index)

1270 (?) Confirmed Eruption  

Episode 1 | Eruption
1270 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1040 (?) Confirmed Eruption VEI: 4

Episode 1 | Eruption Lava dome near eastern summit
1040 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 6 Events for Episode 1 at Lava dome near eastern summit

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Pyroclastic flow
   - - - -    - - - - Lava dome
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
1040
(?)
   - - - - VEI (Explosivity Index)

0880 (?) Confirmed Eruption  

Episode 1 | Eruption
0880 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0260 (?) Confirmed Eruption  

Episode 1 | Eruption
0260 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli

0200 (?) Confirmed Eruption  

Episode 1 | Eruption
0200 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0170 (?) Confirmed Eruption  

Episode 1 | Eruption
0170 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0010 (?) Confirmed Eruption  

Episode 1 | Eruption
0010 (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0180 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0180 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0230 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0230 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0260 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0260 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0460 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0460 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0510 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0510 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

0560 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
0560 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1300 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
1300 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1650 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
1650 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 2 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash

1800 BCE (?) Confirmed Eruption  

Episode 1 | Eruption
1800 BCE (?) - Unknown Evidence from Correlation: Tephrochronology

List of 3 Events for Episode 1

Start Date End Date Event Type Event Remarks
   - - - -    - - - - Explosion
   - - - -    - - - - Ash
   - - - -    - - - - Lapilli
Deformation History

There is no Deformation History data available for Cayambe.

Emission History

There is no Emissions History data available for Cayambe.

GVP Map Holdings

Maps are not currently available due to technical issues.

The maps shown below have been scanned from the GVP map archives and include the volcano on this page. Clicking on the small images will load the full 300 dpi map. Very small-scale maps (such as world maps) are not included.

Smithsonian Sample Collections Database

There are no samples for Cayambe in the Smithsonian's NMNH Department of Mineral Sciences Rock and Ore collection.

External Sites