Big Island Earthquakes: How Common They Are and What to Expect

⚠️ Big Island Safety Notice
The Big Island’s environment can change rapidly — ocean conditions, lava flows, weather, and trails may become dangerous without warning. This guide is for educational purposes only and does not replace real-time assessments, posted warnings, or professional guidance. Always check current conditions before entering the water, hiking, or exploring, and do not proceed if conditions appear unsafe — even if a location is described as “safer.”

This guide explains how common earthquakes are on the Big Island, why they happen, what magnitude to expect, and practical safety tips, making it a reliable resource for anyone exploring the island.

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What Causes Earthquakes on the Big Island?

The Big Island experiences earthquakes primarily due to its volcanic activity. The island sits on the southeastern end of the Hawaiian hotspot, where magma rises through the Earth’s mantle to feed active volcanoes like Kīlauea and Mauna Loa.

Key Causes:

1. Volcanic Activity
   • Movement of magma underground causes the ground to shift, resulting in earthquakes of varying magnitude.
   • Most are small tremors that may be barely noticeable.
2. Fault Lines and Tectonic Stresses
   • While Hawaii is not near major plate boundaries, the island has fault zones that generate earthquakes, particularly in volcanic rift zones.
3. Landslides and Slope Movement
   • The Big Island’s steep volcanic slopes sometimes shift or slump, causing small to moderate earthquakes.

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How Common Are Big Island Earthquakes?

• Daily Tremors: The Big Island experiences dozens of tiny earthquakes each day, most below magnitude 3.0. These are often too small to be felt by people.
• Moderate Earthquakes: Magnitude 4.0–5.0 earthquakes occur occasionally and can rattle windows, furniture, and walls but rarely cause serious damage.
• Large Earthquakes: Magnitude 6.0+ events are rare but possible, usually associated with volcanic rift activity or slope failure.

Seismic Hotspots on the Island:

• Kīlauea Rift Zones: Areas near the volcano’s east rift are most active.
• Mauna Loa Slopes: Magma movement and slope adjustments produce frequent minor quakes.
• Hāmākua and Kaʻū: Occasionally experience moderate tremors due to fault lines and volcanic stress.

Tip: You can track current seismic activity in real-time at the USGS Hawaiian Islands Earthquake Map.

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What to Expect During a Big Island Earthquake

Most earthquakes on the Big Island are small tremors that feel like a brief shake or rattle. Here’s what visitors may experience:

• Magnitude 1–3: Usually not felt, but may register on seismographs.
• Magnitude 3–4: Light shaking; may feel like a passing truck. Windows and hanging items may sway.
• Magnitude 4–5: Noticeable shaking, may rattle dishes, windows, and small furniture. Usually no structural damage.
• Magnitude 5–6: Stronger shaking; unsecured objects may fall. Minor damage possible to poorly constructed buildings.
• Magnitude 6+: Rare but significant; may cause structural damage, landslides, or road closures.

Duration

• Earthquakes from volcanic movement are usually short-lived, lasting only a few seconds to a minute.
• Aftershocks are common and may continue for hours to days following a moderate quake.

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Safety Precautions for Visitors and Residents

Even though most Big Island earthquakes are minor, it’s wise to be prepared.

1. During an Earthquake

• Drop, Cover, and Hold On: Drop to the floor, take cover under sturdy furniture, and hold on until shaking stops.
• Stay Indoors if possible; avoid doors and windows.
• If Outdoors: Move to an open area away from buildings, power lines, and trees.

2. After an Earthquake

• Check for Injuries: Provide first aid if needed.
• Inspect for Hazards: Watch for fallen debris, gas leaks, or damaged structures.
• Expect Aftershocks: These are often smaller than the main quake but can still shake buildings.

3. For Vehicles

• Pull over safely if driving. Avoid stopping under bridges, trees, or power lines.

4. Emergency Preparedness

• Keep a basic emergency kit: water, snacks, flashlight, first-aid supplies, and a phone charger.
• Know evacuation routes if visiting volcanic zones or coastal areas.
• Stay updated via Hawai’i Civil Defense Alerts.

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Common Questions About Big Island Earthquakes

Are Big Island Earthquakes Dangerous for Tourists?

• Most earthquakes are minor tremors, posing little risk.
• Hazards increase near active volcanic rift zones or steep slopes prone to landslides.

Can Earthquakes Trigger Tsunamis?

• Hawaii has tsunami warning systems, but most quakes on the Big Island do not generate tsunamis.
• Local authorities issue alerts if there’s any tsunami risk.

Do Earthquakes Cause Lava to Flow?

• Small quakes do not directly trigger lava flows, but significant movement in volcanic rift zones may precede or coincide with lava activity.

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How Scientists Track Earthquakes on the Big Island

• Seismographs: Installed across the island to detect even tiny tremors.
• USGS Hawaiian Volcano Observatory (HVO): Monitors volcanic activity, including earthquakes, gas emissions, and ground deformation.
• Mobile Apps and Maps: Tourists can access real-time earthquake data for awareness.

Link: USGS Hawaiian Islands Earthquake Map

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Tips for Tourists Visiting Seismic Areas

1. Plan Your Activities Wisely: If hiking near rift zones or steep slopes, know safe paths and evacuation routes.
2. Stay Informed: Check civil defense alerts and local news.
3. Respect Closure Signs: Certain trails may be closed after earthquakes or due to volcanic hazards.
4. Travel Insurance: Consider policies that cover natural events for peace of mind.
5. Children and Pets: Keep them close, especially on trail hikes or near cliffs.

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Real-World Examples

• May 2018 Kīlauea Eruption: Hundreds of small earthquakes preceded the eruption, some felt as magnitude 5 tremors.
• 2019 Hāmākua Tremor Series: Minor quakes rattled homes and caused small rockfalls.
• Ongoing Daily Tremors: Even today, the Big Island experiences dozens of micro-earthquakes daily—most are imperceptible to humans but important for scientific monitoring.

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Key Takeaways

1. Earthquakes are common on the Big Island, but most are minor tremors.
2. Volcanic activity is the primary cause, with rift zones being hotspots.
3. Moderate to large earthquakes are rare but possible, especially near active volcanoes.
4. Safety is simple: Drop, cover, and hold on; monitor alerts; stay on trails.
5. Being prepared and informed ensures you can safely enjoy the Big Island while respecting its geological activity.

By understanding why earthquakes occur, how frequent they are, and what to expect, visitors can enjoy Hawaii’s unique landscapes safely, without unnecessary worry.

Continue reading about the Big Island’s volcanic and geological history here

⚠️ Quick Safety Reminder
Conditions can change suddenly. Always check local conditions, warnings, and official guidance before entering the ocean, lava areas, or trails. Safety is your responsibility.