QuakeScout

Major Fault Lines Worldwide

Explore the world's most seismically active fault lines and tectonic boundaries.

San Andreas Fault

transform1,200 km

The San Andreas Fault is a 1,200 km transform plate boundary that runs through California, marking the junction between the Pacific and North American plates. It is one of the most studied and most dangerous fault systems in the world, capable of producing catastrophic earthquakes.

Countries: United States

VERY HIGH RISK

Hayward Fault

strike-slip74 km

The Hayward Fault runs along the eastern side of San Francisco Bay through densely populated urban areas. Often called the most dangerous fault in America due to the sheer number of people and critical infrastructure directly on top of it.

Countries: United States

VERY HIGH RISK

San Jacinto Fault

strike-slip210 km

The San Jacinto Fault is one of the most seismically active faults in Southern California. It branches off the San Andreas Fault and has produced more M6+ earthquakes than any other fault in the region over the past century.

Countries: United States

VERY HIGH RISK

Calaveras Fault

strike-slip123 km

The Calaveras Fault extends from San Ramon south to Hollister in the San Francisco Bay Area. It exhibits both creep and sudden rupture behavior, posing a significant seismic risk to Silicon Valley communities.

Countries: United States

HIGH RISK

Cascadia Subduction Zone

subduction1,000 km

The Cascadia Subduction Zone is a 1,000 km megathrust fault stretching from northern California to British Columbia. Its last full rupture in 1700 produced a M9.0 earthquake and a tsunami that reached Japan. It is considered overdue for another major event.

Countries: United States, Canada

VERY HIGH RISK

New Madrid Seismic Zone

intraplate240 km

The New Madrid Seismic Zone is the most active seismic zone in central and eastern North America. The 1811-1812 earthquake sequence produced three M7+ events that rang church bells in Boston and temporarily reversed the flow of the Mississippi River.

Countries: United States

HIGH RISK

Wasatch Fault

normal350 km

The Wasatch Fault runs along the western base of the Wasatch Range through Utah's most densely populated corridor. It is a major normal fault with evidence of repeated large earthquakes over the past 6,000 years.

Countries: United States

HIGH RISK

Japan Trench

subduction800 km

The Japan Trench is a subduction zone where the Pacific Plate dives beneath the Okhotsk Plate off the northeast coast of Japan. The 2011 Tohoku earthquake and tsunami killed nearly 20,000 people and triggered the Fukushima nuclear disaster.

Countries: Japan

VERY HIGH RISK

Nankai Trough

subduction700 km

The Nankai Trough runs along the southern coast of Japan where the Philippine Sea Plate subducts beneath the Eurasian Plate. Historical records show devastating earthquakes every 100-200 years, and the next major rupture could produce a M9+ event with a massive tsunami.

Countries: Japan

VERY HIGH RISK

Philippine Trench

subduction1,320 km

The Philippine Trench is one of the deepest trenches on Earth at over 10,500 meters, running along the eastern coast of the Philippines. It marks the subduction of the Philippine Sea Plate and has generated numerous destructive earthquakes and tsunamis.

Countries: Philippines

VERY HIGH RISK

Java Trench

subduction3,000 km

The Java Trench (also called the Sunda Trench) is the deepest point in the Indian Ocean, stretching along the southern coast of Indonesia. It is part of the larger Sunda subduction system responsible for some of the most devastating earthquakes in recorded history.

Countries: Indonesia

VERY HIGH RISK

Sunda Megathrust

subduction5,500 km

The Sunda Megathrust extends from Myanmar through Sumatra to Java, where the Indo-Australian Plate subducts beneath the Eurasian Plate. The 2004 Indian Ocean earthquake and tsunami along this fault killed over 230,000 people in 14 countries, making it one of the deadliest natural disasters in history.

Countries: Indonesia, Myanmar, India

VERY HIGH RISK

Alpine Fault

transform600 km

The Alpine Fault runs almost the entire length of New Zealand's South Island along the Southern Alps. It ruptures in major earthquakes roughly every 300 years, and over 300 years have now passed since the last event, making it one of the most predictable major fault systems on Earth.

Countries: New Zealand

VERY HIGH RISK

North Anatolian Fault

strike-slip1,500 km

The North Anatolian Fault is one of the most active and best-studied strike-slip faults in the world. It has exhibited a remarkable westward migration of large earthquakes over the past century, with the next expected rupture segment directly threatening Istanbul and its 16 million inhabitants.

Countries: Turkey

VERY HIGH RISK

East Anatolian Fault

strike-slip700 km

The East Anatolian Fault forms the boundary between the Anatolian and Arabian plates. The devastating February 2023 earthquake doublet (M7.8 and M7.5) killed over 50,000 people in Turkey and Syria, making it one of the deadliest earthquakes of the 21st century.

Countries: Turkey

VERY HIGH RISK

Dead Sea Transform

transform1,000 km

The Dead Sea Transform is a left-lateral transform fault connecting the spreading Red Sea to the collision zone in southern Turkey. It runs through the Jordan Rift Valley and has produced historically significant earthquakes, including events referenced in ancient texts.

Countries: Israel, Jordan, Lebanon, Syria

HIGH RISK

East African Rift

divergent3,500 km

The East African Rift is an active continental rift zone where the African Plate is splitting into the Nubian and Somali plates. Over millions of years, this process will eventually create a new ocean basin. Though less seismically intense than subduction zones, it produces regular moderate earthquakes.

Countries: Ethiopia, Kenya, Tanzania, Uganda, Malawi, Mozambique

MODERATE RISK

Mid-Atlantic Ridge

divergent16,000 km

The Mid-Atlantic Ridge is the longest mountain range on Earth, running 16,000 km along the floor of the Atlantic Ocean. It is a divergent boundary where the Eurasian and North American plates pull apart. Iceland is the most prominent location where the ridge rises above sea level.

Countries: Iceland

MODERATE RISK

Himalayan Frontal Thrust

thrust2,400 km

The Himalayan Frontal Thrust marks where the Indian Plate collides with and slides beneath the Eurasian Plate, building the Himalayas. A large seismic gap in the central Himalayas has not ruptured since 1505, accumulating enormous strain that could release in a M8.5+ earthquake affecting hundreds of millions.

Countries: India, Nepal, Bhutan

VERY HIGH RISK

Main Central Thrust

thrust2,200 km

The Main Central Thrust is a major geological fault in the Himalayan mountain system, running roughly parallel to the Himalayan Frontal Thrust but deeper within the range. It played a key role in the uplift of the High Himalayas and remains seismically active with significant M7+ earthquake potential.

Countries: India, Nepal, Pakistan

HIGH RISK

Sagami Trough

subduction250 km

The Sagami Trough lies south of Tokyo Bay where the Philippine Sea Plate subducts beneath the North American Plate. The 1923 Great Kanto Earthquake killed over 100,000 people and destroyed most of Tokyo and Yokohama. The same trough threatens the Tokyo metropolitan area today.

Countries: Japan

VERY HIGH RISK

Atacama Fault

strike-slip1,000 km

The Atacama Fault System is a major north-south trending fault running through the Atacama Desert in northern Chile. It is one of the longest continuous fault systems in South America, active since the Jurassic period, and closely linked to the subduction processes along the Chilean coast.

Countries: Chile

HIGH RISK

Nazca Plate Boundary

subduction5,900 km

The Nazca Plate subducts beneath the South American Plate along the entire western coast of South America. This boundary has produced the largest earthquake ever recorded — the 1960 M9.5 Valdivia earthquake — and continues to generate frequent major seismic events across the region.

Countries: Chile, Peru, Ecuador, Colombia

VERY HIGH RISK

Denali Fault

strike-slip660 km

The Denali Fault is a major intracontinental strike-slip fault curving through the Alaska Range near Denali (Mount McKinley). The 2002 earthquake produced one of the longest surface ruptures ever observed at 340 km, yet caused minimal casualties due to Alaska's sparse population.

Countries: United States

HIGH RISK

Queen Charlotte Fault

transform900 km

The Queen Charlotte Fault is a major transform fault off the coast of British Columbia, often called Canada's San Andreas. It marks the boundary between the Pacific and North American plates and is one of the most seismically active regions in Canada, producing the country's largest recorded earthquake (M8.1 in 1949).

Countries: Canada

VERY HIGH RISK

Reelfoot Rift

intraplate300 km

The Reelfoot Rift is an ancient failed rift (aulacogen) buried beneath the Mississippi Embayment. Though it formed over 500 million years ago, it remains a zone of weakness in the continental crust that concentrates stress, generating the powerful New Madrid earthquake sequence of 1811-1812.

Countries: United States

HIGH RISK

Hellenic Arc

subduction1,000 km

The Hellenic Arc is a subduction zone where the African Plate dives beneath the Aegean Sea Plate south of Greece. It produced the massive 365 AD earthquake and tsunami that devastated ancient Alexandria. The region continues to be one of the most seismically active areas in Europe.

Countries: Greece, Turkey

VERY HIGH RISK

Caribbean Plate Boundary

subduction3,200 km

The Caribbean Plate boundary is a complex system involving subduction, transform, and compressional faults surrounding the Caribbean Sea. The 2010 Haiti earthquake killed over 200,000 people and highlighted the extreme vulnerability of the region's cities to seismic events.

Countries: Haiti, Dominican Republic, Jamaica, Puerto Rico, Trinidad and Tobago, Venezuela, Colombia

VERY HIGH RISK

Manila Trench

subduction800 km

The Manila Trench runs along the western side of Luzon in the Philippines, where the South China Sea basin subducts eastward beneath the Philippine Mobile Belt. A major rupture could generate a devastating tsunami threatening Manila and coastal cities around the South China Sea.

Countries: Philippines, Taiwan

VERY HIGH RISK

Altyn Tagh Fault

strike-slip2,500 km

The Altyn Tagh Fault is one of the longest strike-slip faults on Earth, extending across the northern edge of the Tibetan Plateau. It accommodates much of the northward motion of the Indian Plate and plays a critical role in the lateral extrusion of Tibet. Despite its remoteness, it poses M8+ earthquake risk.

Countries: China

HIGH RISK

Ring of Fire

subduction40,000 km

The Ring of Fire is a 40,000 km horseshoe-shaped belt of subduction zones, volcanic arcs, and transform faults encircling the Pacific Ocean. It accounts for approximately 90% of the world's earthquakes and 81% of the world's largest earthquakes, as well as 75% of the world's active volcanoes.

Countries: Japan, Philippines, Indonesia, New Zealand, Chile, United States, Canada, Mexico, Russia

VERY HIGH RISK

Kunlun Fault

strike-slip1,500 km

The Kunlun Fault runs along the northern edge of the Tibetan Plateau for 1,500 km. The 2001 earthquake produced a 426 km surface rupture — one of the longest ever recorded. Though it traverses sparsely populated terrain, it plays a critical role in accommodating India-Asia collision deformation.

Countries: China

HIGH RISK

Enriquillo-Plantain Garden Fault

strike-slip600 km

The Enriquillo-Plantain Garden Fault is a major left-lateral strike-slip fault running through the southern peninsula of Haiti and into Jamaica. The catastrophic 2010 earthquake ruptured only a portion of this fault, leaving adjacent segments with accumulated strain capable of producing further devastating earthquakes.

Countries: Haiti, Jamaica

VERY HIGH RISK

Chaman Fault

strike-slip860 km

The Chaman Fault is a major transform fault marking the western boundary of the Indian Plate against the Eurasian Plate. The devastating 1935 Quetta earthquake killed over 30,000 people. Significant strain continues to accumulate along locked segments, posing a major seismic hazard to the region.

Countries: Pakistan, Afghanistan

HIGH RISK

Puente Hills Thrust

thrust40 km

The Puente Hills Thrust is a blind thrust fault running directly beneath downtown Los Angeles. Though only 40 km long, it is considered one of the most dangerous faults in the United States because a rupture would occur directly beneath the densely populated LA basin, potentially causing catastrophic damage.

Countries: United States

VERY HIGH RISK