By Paige Cross           

 

 

Keeping Track of Colima

Monitoring

 

The official website of the volcanological observatory monitoring Colima, which provides a wealth of information on the volcano, including summaries of its historical activity and its basic, tectonic, and geologic characteristics; descriptions of the seismic, visual, and deformation monitoring the observatory is currently engaged in; as well as discourse on precautions that can be taken, potential hazards, and advice on dealing with a disaster.

Provides daily updates of Colima's volcanic activity, as well as relevant conditions and outstanding advisories. 

A Java animation of satellite images taken over the volcanic setting.  Updated every half hour. 

It should be pretty clear already.

 

How Do They Do it?

The monitoring activity at Volcán de Colima includes the recording of volcanic and tectonic seismic activity, ground deformation, thermometry, and meteorology; receiving infrared and visible satellite imagery from AVHRR and GOES; and performing geological surveys at the volcano and in the surrounding areas.  Prior to the September 1992 publication of the report from which this information was gathered, there were five Telemetric seismic stations, each with short-period vertical seismometers, located on and in the vicinity of the volcano, and two located in the depression between the tectonic fault systems of Colima. However, there were plans to add three more stations before the year’s end, putting one on the volcano, one in the depression, and one in the subduction zone, for a total of ten stations in the Red Sísmica de Colima (RESCO). Other equipment as of 1992 included: 3 portable three-component digital stations for registration onsite, a Blum tiltmeter, two Telemetric meteorological stations, one Telemetric thermometric station, a deformation network of benchmarks, a VHF/FM communication system, and the capacity for receiving infrared and visible images from meteorological satellite.20

Current deformation monitoring at Colima includes the usage of electric distance measurement, which measures distance from a fixed point to reflectors on the edifice and GPS networks, which can measure the changes in a geodetic network; electronic and dry inclinometers, which, respectively, record the changes of a plane and determine angles of tilt and precisely determine variations of the network that can be attributed to the movement of the deformation source; trigonometrical and geometrical leveling, which detect uplift or depression at points on the edifice, and gravimetry, which measures changes in a gravitational field.21

Geochemical monitoring at Colima is particularly important at Colima, especially in terms of its usefulness in predicting eruptions.  Where seismic anomalies often fail to accurately indicate an eruption, gas emissions, for example, can signal important changes that may be nearly definitive hallmarks of impending activity. Therefore, in addition to the heavily-relied-upon seismic data, information concerning sulfur dioxide levels, the gas composition of eruption plumes and the atmospheric surroundings, the chemical composition of lava and spring waters, and the characteristics of the ash produced are also closely monitored and studied.23

Visual monitoring, although highly dependent on weather conditions, has been utilized to observe and record the activity at the Volcán de Colima since 1998, capturing dome growth; lava, block-and-ash, and pyroclastic flows; explosions; ash fall; ballistics; and even subsequent forest fires.  It also records the more mundane behaviors, including the eruption and height of a volcanic plume, a change in color, and the formation of new fumaroles, for instance. This method of monitoring operates twenty-four hours a day at two stations: Estación Naranjal, located 15 km south of the volcano at the Volcano Observatory in El Naranjal, and Estación Nevado, located 5.3 km north of the volcano on Nevado de Colima, which both broadcast to the Volcano Observatory of the University of Colima. According to the site, eight more cameras are being installed at various points around the volcano in order to assist in the monitoring activities.22

It is also helpful to read scientific articles on current research being done at Colima in order to see the various monitoring sources available to and used by geologists and volcanologists interested in this volcano.

Suggested reading:

  • "Recent lahars at Volcan de Colima (Mexico): Drainage variation and spectral classification"

  • "Modeling of pyroclastic flows of Colima Volcano, Mexico: implications for hazard assessment"

  • "Debris avalanches and debris flows transformed from collapses in the Trans-Mexican Volcanic Belt, Mexico - behavior, and implications for hazard assessment"

Available through ScienceDirect and links on the Sources page.