Stratovolcano โข Halmahera, Indonesia
Possible, not imminent
An eruption at Gamalama in any given year is a real but minority possibility. Our model estimates a 26.3% chance of an eruption in the next 12 months โ about one eruption every ~3 years on average. Its most recent known eruption was 2018.
Statistical estimate, not a prediction โ medium confidence. Always follow official volcano observatory advisories. How this is calculated โ
26.3%
1-year
2.5%
30-day
~3y
recurrence
0.800ยฐ, 127.325ยฐ ยท Indonesia ยท 12 nearby earthquakes
26.3%
1-year probability
2.5%
30-day
~3y
Avg. recurrence
high
Risk level
~1 eruption every 3 yr โ the GVP eruption frequency blended toward a stratovolcano prior by how complete the record is.
84 dated eruptions over ~508 yr โ a well-documented record the rate can rely on.
Most eruptions ~VEI 2; no large (VEI โฅ 4) eruption in the documented record.
A recently active volcano gets a higher near-term rate; a long-dormant one is tempered.
No live PHIVOLCS/seismic feed for this volcano, so short-term precursors and alert levels are not applied.
Confidence: A monitoring network and a multi-eruption history constrain the estimate, but with meaningful uncertainty.
How this is calculated โPoisson estimate from the GVP eruption frequency, blended toward a volcano-type prior by how complete the record is and adjusted for recency โ 1-year range 19.6โ34.8% (confidence medium; no live seismic feed for this volcano). Philippine volcanoes additionally use live PHIVOLCS alert levels and seismicity โ see the Risk Analysis dashboard.
explosive ยท moderate explosivity
Largest recorded: VEI 3
Most eruptions ~VEI 2; no large (VEI โฅ 4) eruption in the documented record.
84 dated eruptions over ~508 yr โ a well-documented record the rate can rely on.
Size from the volcano's VEI record combined with the global eruption sizeโfrequency relation; the record grade reflects how complete its eruptive history is โ sparse records lean on a volcano-type prior with wider uncertainty. How this is calculated โ
1,715m
Elevation
2018
Last Eruption
VEI 2
Explosivity Index
Stratovolcano
Type
18 km N of Sofifi, Indonesia
10.0km deep โข 30km away
38 km NNE of Ternate, Indonesia
151.0km deep โข 40km away
40 km N of Ternate, Indonesia
150.8km deep โข 41km away
46 km NW of Ternate, Indonesia
160.0km deep โข 42km away
49 km NW of Ternate, Indonesia
42.6km deep โข 44km away
51 km NNW of Ternate, Indonesia
43.5km deep โข 47km away
58 km WNW of Ternate, Indonesia
23.7km deep โข 52km away
Molucca Sea
30.2km deep โข 54km away
61 km WSW of Ternate, Indonesia
122.4km deep โข 57km away
64 km WSW of Ternate, Indonesia
34.8km deep โข 59km away
69 km NW of Ternate, Indonesia
78.0km deep โข 64km away
70 km WNW of Ternate, Indonesia
80.8km deep โข 64km away
Coordinates
0.8000ยฐN, 127.3250ยฐE
Region
Indonesia
Bars are relative to the 100 km total.
๐ Scientific Note: Volcanic risk assessments use peer-reviewed seismic-volcanic correlation models (Nishimura 2017, Jenkins 2024). These represent statistical probabilities, not predictions. Always follow official PHIVOLCS advisories.
How this is calculated โFAQ
An eruption at Gamalama in any given year is a real but minority possibility. Based on Gamalama's eruption history, our model estimates roughly a 26.3% chance of an eruption within the next 12 months (about one eruption every 3 years on average). This is a statistical estimate, not a definite prediction โ always follow official volcano observatory advisories.
Gamalama's most recent known eruption was 2018 (per the Smithsonian Global Volcanism Program record).
Gamalama is classified as active. It is a stratovolcano in Halmahera, Indonesia, rising to 1,715 m.
About 300,000 people live within 30 km of Gamalama and roughly 500,000 within 100 km. The current modeled hazard level is high. Local hazard zones and typical eruption size are detailed on this page.
Gamalama is located in Halmahera, Indonesia, at 0.800ยฐ, 127.325ยฐ, with a summit elevation of 1,715 m.