🌋VolcanoAtlas

Santa María

Guatemala's Plinian Giant and Its Ever-Growing Dome

Elevation

3,745 m

Last Eruption

2025 (Santiaguito dome ongoing)

Type

Stratovolcano

Country

Guatemala

Location

Loading map...

Volcanic Hazards & Risk Assessment

Primary Hazards

  • Pyroclastic flows
  • Lava flows
  • Volcanic bombs and ballistics
  • Lahars and mudflows

Risk Level

Population at RiskLow
Infrastructure RiskHigh
Aviation RiskSignificant

Geological Composition & Structure

Rock Types

Primary
Unknown
Silica Content
Varied composition

Tectonic Setting

Unknown
Intraplate setting with hotspot or regional volcanic activity.

Age & Formation

Epoch
Unknown
Evidence
Unknown

Eruption Statistics & Analysis

MetricValueGlobal RankingSignificance
Total Recorded EruptionsUnknownLowModerately active volcano
Maximum VEIVEI UnknownMinorLocal impact potential
Recent Activity1 years agoVery RecentCurrently active

Monitoring & Alert Status

Monitoring Networks

Global Volcanism Program
International eruption database

Current Status

Active
Recent volcanic activity detected. Continuous monitoring in place.

Authority Sources

Smithsonian GVP
Official volcano database

Related Volcanoes

All Guatemala Volcanoes
Explore by country
Stratovolcano Volcanoes
By volcano type
Western Highlands
Regional volcanoes

Other Volcanoes in Guatemala

Interesting Facts

🌋

The 1902 eruption of Santa María was one of the four largest volcanic eruptions of the 20th century, rated VEI 6 on the Volcanic Explosivity Index.

🌋

Santa María had no recorded historical eruptions before 1902 — the population living on its flanks had no idea the forested mountain was an active volcano.

🌋

The eruption column on October 24, 1902, reached an estimated 27–28 km (89,000–92,000 ft) into the stratosphere, one of the tallest of the 20th century.

🌋

An estimated 8.5–10 km³ of dacitic tephra was ejected during the approximately 18–20-hour-long eruption.

🌋

The Santiaguito dome has been erupting continuously since June 22, 1922 — over 100 years of uninterrupted volcanic activity.

🌋

Santiaguito consists of four overlapping domes (El Caliente, La Mitad, El Monje, El Brujo) that grew sequentially, with activity migrating eastward.

🌋

The combined volume of the Santiaguito dome complex now exceeds 1.1 km³ of extruded material.

🌋

Santa María was designated one of 16 'Decade Volcanoes' by the International Association of Volcanology due to its hazard potential and proximity to populations.

🌋

The 1902 eruption struck just five months after the devastating magnitude 7.5 earthquake of April 18, 1902, compounding Guatemala's suffering.

🌋

In 1929, a catastrophic pyroclastic flow from Santiaguito killed hundreds of people in the Río Samalá valley.

🌋

Coffee grown on Santa María's fertile volcanic slopes is among Guatemala's most prized, with several world-renowned fincas on the lower flanks.

🌋

The summit hike offers a rare opportunity to watch an active dome eruption from above — Santiaguito's small explosions are often visible at dawn from the 3,745 m peak.

Frequently Asked Questions

Is Santa María volcano still active?
Yes, Santa María is an active stratovolcano in Guatemala. While the main cone last erupted explosively in 1902, the Santiaguito lava-dome complex on its southwest flank has been erupting continuously since June 1922 — more than a century of uninterrupted activity. Santiaguito produces near-daily small explosive eruptions, periodic lava extrusion, and occasional pyroclastic flows. The volcano is monitored by Guatemala's INSIVUMEH and is classified as one of the world's 16 Decade Volcanoes due to its persistent hazard to nearby populations, including the city of Quetzaltenango with approximately 300,000 residents.
What happened during the 1902 eruption of Santa María?
On October 24, 1902, Santa María erupted in a massive VEI 6 Plinian explosion after possibly thousands of years of dormancy. The eruption column reached 27–28 km into the stratosphere and ejected 8.5–10 km³ of dacitic tephra over approximately 18–20 hours. The blast carved a 1.5-km-wide crater into the volcano's southwest flank. Between 5,000 and 6,000 people were killed by building collapse, pyroclastic flows, and post-eruption disease and famine. It was one of the four largest eruptions of the 20th century, comparable in magnitude to the 1991 eruption of Mount Pinatubo.
What is Santiaguito?
Santiaguito is a dacitic lava-dome complex growing within the 1902 explosion crater on Santa María's southwest flank. It began forming on June 22, 1922, and has been erupting continuously ever since — making it one of the longest-running eruptions on Earth. The complex consists of four overlapping domes: El Caliente, La Mitad, El Monje, and El Brujo, with activity now centered on El Caliente. Santiaguito produces frequent small explosions, lava extrusion, pyroclastic flows, and lahars that threaten downstream communities along the Río Samalá.
How tall is Santa María volcano?
Santa María stands 3,745 m (12,287 ft) above sea level, making it one of the tallest volcanoes in Guatemala and Central America. The summit rises approximately 3,000 m above the Pacific coastal plain to its south, giving it dramatic topographic prominence. Before the 1902 eruption, the volcano had a more symmetrical profile; the massive 1.5-km-wide explosion crater on the southwest flank now breaks the cone's symmetry. The Santiaguito dome complex at the crater's base reaches approximately 2,530 m elevation.
Can you hike Santa María volcano?
Yes, Santa María is one of Guatemala's premier volcanic hikes. Most climbers depart from the trailhead near Llano del Pinal above Quetzaltenango around 3:00–4:00 AM to reach the 3,745 m summit for sunrise. The ascent takes 3–5 hours over steep, forested terrain and gains roughly 1,400 m of elevation. The reward is a dramatic panorama including views of the active Santiaguito dome far below, often visibly erupting. The hike is strenuous but non-technical; guided tours are recommended for safety and navigation. Quetzaltenango serves as the base for all treks.
Is Santa María dangerous?
Santa María–Santiaguito is considered one of the most hazardous volcanic systems in Central America. Quetzaltenango, with approximately 300,000 inhabitants, lies just 10 km from the summit. The Santiaguito dome generates ongoing pyroclastic flows and lahars that regularly threaten communities along the Río Samalá drainage. The 1902 eruption killed an estimated 5,000–6,000 people, and a 1929 dome-collapse pyroclastic flow killed hundreds more. A future large explosive eruption or major dome collapse remains a plausible scenario. The volcano is one of 16 globally designated Decade Volcanoes.
How does Santa María compare to other large eruptions?
Santa María's 1902 eruption was rated VEI 6, placing it among the most powerful eruptions of the 20th century. It is comparable in magnitude to the 1991 eruption of Mount Pinatubo (VEI 6, Philippines) and exceeded in the 20th century only by the 1912 eruption of Novarupta in Alaska (VEI 6, but with larger volume). In historical context, VEI 6 eruptions are roughly 10 times less powerful than the VEI 7 eruption of Tambora in 1815, which caused the 'Year Without a Summer.' The 1902 eruption ejected 8.5–10 km³ of tephra.
What type of volcano is Santa María?
Santa María is a stratovolcano (also called a composite volcano), built from alternating layers of lava flows and pyroclastic deposits. Its main cone is composed primarily of basaltic-andesite to dacitic material. The volcano is part of the Central America Volcanic Arc, formed by the subduction of the Cocos Plate beneath the Caribbean Plate. The Santiaguito dome on its flank represents a lava-dome style of eruption, where viscous dacitic magma extrudes slowly rather than exploding violently, though Santiaguito also produces explosive events.