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due to the success of the volcanic activity thread i thought we could this thread to discuss and report on seismic activity around the world Earthquakes reported here must be 5th magnitude or over and can occur anywhere in the world So i may aswell start off : on friday 9th may 2008 there was a magnitude 6.7 earthquake reported in the Guam Region at around 21:51 UTC (22:51 BST) (see map below) Info on activity (from USGS) :- Magnitude : 6.7 Date - Time : Friday, May 09, 2008 at 21:51:31 UTC Loacation : 12.509°N, 143.157°E Depth : 87.6 km (54.4 miles) Region : GUAM REGION Distances : 205 km (125 miles) WSW of HAGATNA, Guam 285 km (180 miles) SW of Rota, Northern Mariana Islands 405 km (250 miles) SW of SAIPAN, Northern Mariana Islands 505 km (315 miles) SSW of Anatahan, Northern Mariana Islands Location Uncertanity : horizontal +/- 5.3 km (3.3 miles); depth +/- 12.9 km (8.0 miles) Parameters : NST=246, Nph=246, Dmin=220.6 km, Rmss=0.98 sec, Gp= 25°, M-type=moment magnitude (Mw), Version=8 Source : USGS NEIC (WDCS-D) Event ID : us2008rvcj *The Event has been reviewed by a seismologist

Introduction My intention is to produce a series of articles (depending on interest) which introduces ideas about volcanic and earthquake activity. I want to go slightly off the beaten track to explore oddities, volcano hazards, analysis methods, Wonders and Mankind’s impacts. Keep in mind I am not expert (corrections gratefully received), but hopefully these will at least give a flavour of some different places in the world and provide a few minutes escape from people’s troubles. Introducing Volcano Mount Karthala Reason for Interest This is a very active volcano with a history of collapse, lava flows reaching the sea, going through a step change in activity in a tectonic environment that can create new large volcanoes. For me this is a very dangerous volcano which will cause issues in the near future. The Setting Named after the Arabic word for moon the Comoros Islands are volcanic islands between the coast of Mozambique and the island of Madagascar consisting of four islands – Ngazidja (Grande Comore), Moheli, Anjouan and Mayotte. Originally the Comoros were known as the ‘Perfume Islands’ due to their fragrant flowers, like the yellow ylang-ylang, used in perfumes which where imported and cultivated by French colonialists. While Mayotte remains under French Administration the rest of the islands became an independent nation in 1975. Grande Comore is the largest of the Comoros Islands with the capital city (Moroni) of the nation located there. The whole western side of Grande Comore is full of very highly rated beaches with Ndroudé being the longest and widest and Mitsamiouli Beach being considered one of the top beaches in the world. In the far northern part of the island is the small crater lake 'Lac Sale' which the locals call the bottomless lake probably due to some professional divers who tried to explore the lake but never came back. South of Moroni is Iconi which was once the capital of the Sultanate of Bambao and the first capital of Comoros. Moroni has a distinctly relaxed Arabian pace of life with the labyrinthine medina at the center which is crisscrossed by cobbled alleyways that are lined with intricately carved doorways, ornate mosques and charming Middle Eastern-style cafes. Moroni’s principal landmark is the two-storied and gleaming white 15th-century Old Friday mosque ( Nouvelle Mosquee de Vendredi Mosque dating back to around 1427) restored in the 1920s by France to pay tribute to those Comorians killed fighting for them during the First World War. The islands have a tropical climate with two clearly marked seasons: a cooler, dry period between May and October and a warmer, humid season between November and April. In November the summer monsoon (kashkazi) brings the highest afternoon temperatures—about 33 °C. The highest monthly rainfall occurs in January with about 11–15 inches. Dry season daily maximum temperatures fall to their lowest 29 °C in July. The average annual rainfall varies between 40 to 100 inches being highest on the windward northeast sides of the islands. The island has a coastal zone of mangroves followed inland by a zone of coconut palms, mangoes, and bananas up to about 1,300 feet. Above this a forest zone of Mohogany and orchids rises to about 5,900 feet where they give way to broom, heather, and lichens. Additional aromatic plants such as frangipani (Plumeria), jasmine, and lemongrass lend a delightful fragrance to the islands. The Tectonic environment The Comoros islands are roughly W-NW aligned and extend over 270 km in the Western Indian Ocean, on the northern edge of the Mozambique channel. The channel formed by the opening of the Somali and Mozambique Basins which dislocated the micro continent Madagascar to the south, away from the African continental plate. It was thought that a hotspot migrated under the chain of islands propagating to the northwest creating the volcanic Islands. This chain of volcanic islands and seamounts becomes progressively older from the still-active volcanism at Grande Comoros toward the older volcanic areas in northern Madagascar. Volcanic activity history and aging are not really consistent with a migrating hotspot as older volcanoes don't seem to be becoming less active. It is now proposed that East Africa consists of smaller sub plates and it is the twisting between these sub plates that has given rise to the islands. The clockwise rotation of Somalia relative to Lwandle creates a right-lateral shear zone which causes ripping and rifting along the sub plate boundary where the Comoros Islands are. A zone of broad deformation extends from the eastern boundary of the Rovuma microplate, across the Comoros Islands, and including parts of central and northern Madagascar. This does not explain volcanic rock analysis from the islands which still suggest a deep mantle source for Magma, so we might expect some refinement of tectonics in the area over time. 2018 Earthquake Mystery On 10 May 2018, an unprecedented long and intense seismic crisis started offshore, east of Mayotte, the easternmost of the Comoros volcanic islands. The population felt hundreds of events. Seismic activity began with a swarm of thousands of seemingly tectonic earthquakes then changed around June to a completely new form of earthquake signal which was so strong that it could be recorded up to a thousand kilometers away. These 20 to 30 minute long signals are characterized by particularly harmonic, low frequencies, similar to a large bell or a double bass, and are called Very Long Period (VLP) signals. French researchers have now identified the source of the puzzling activity as the birth of a submarine volcano some 31 miles off Mayotte's eastern shore. Sitting about two miles underwater, the new volcano stretches nearly half a mile high and extends up to three miles across. The Volcano Mount Karthala is an active volcano and the highest point of the Comoros Nation at 2,361 m above sea level. It is the southernmost and larger of the two shield volcanoes forming Grande Comore island (the other volcano being La Grille volcano). The Karthala volcano is very active, having erupted more than 20 times since the 19th century and is considered the youngest volcano in the island group. Frequent eruptions have shaped the volcano's summit caldera with two well developed rift zones intersecting at the summit caldera complex. Mount Karthala features eight or more overlapping calderas, nested pit craters and several terraces which are aligned in a sort of diamond shape. The center of the caldera complex is occupied by the crater “Choungou Chahalé”, the older main crater, which consists now of two inner pits. Another crater is “Choungou Changouméni”, a small circular pit crater of 220 m diameter in the northern lobe of the caldera, next to a small scoria cone from 1972. Around my inner crater, fumaroles emit superheated steam with a sulphurous odour. Elongated rift zones extend to the NNW and SE from the summit. The lower SE rift zone forms the Massif du Badjini, a peninsula at the SE tip of the island. A sharp landslide scarps constitutes the northern limit of the Badjini massif at the SE end of Grande Comore. This landslide scarp is evidence of a large failure of the E flank of Mt. Karthala. Past Eruptions Two strong eruptions in 1972 and 1977 did significant damage as lava flows reached the ocean. In 1977, the coastal village of Singani was partly destroyed by lava flows. In 1860, a lava flow even reached the coast close to the island capital where you will find a number of lava tubes. The 1991 eruption marks the beginning of a style change in Karthala’s behaviour. The eruption followed three months of increasing seismicity and inflation. After several hours of relative calm a sizeable phreatic explosion further enlarged Choungou Chahalé and lowered its floor. In a visit to the summit two weeks after the 11 July explosion people heard a “fountaining” sound, but no lava fountains or any other source were visible. It turned out later that this would have been the sound of the forceful arrival of water into the new crater, forming a crater lake for the first time. Scientists believe now, that this explosion had changed the hydrothermal system below the volcano, as all following eruptions were phreato-magmatic in nature. Recent Activity 2005 eruption During April inhabitants heard a rumbling coming from the volcano and observed an ash column above the summit. The first ash-fall deposits began to form soon afterwards on the island's eastern side. According to the firsts reports, ash deposition increased and continued accompanied by a strong smell of sulfur. Observers saw a very dark plume spreading into a mushroom shape and accompanied by lightning flashes. Some inhabitants panicked and fled the island's eastern villages. During the next few days ash continued to fall on the eastern part of the island and were heavy enough to require inhabitants to use umbrellas to get about. A pilot for Comoros Aviation, flew over the west flank and observed a large plume in the direction of the Chahalé crater and observed airborne molten ejecta. As the eruption continued authorities decided to evacuate some 30,000 residents from eastern villages. The following days saw ash falls on the island's western and northern parts, notably, on the country's capital city of Moroni and on the Hahaya airport. Lahars damaged roads and hundreds of houses, affecting thousands of inhabitants at the foot of Karthala volcano. Eruptions continued through to later in the year when investigators ascended Karthala and observed a molten-surfaced lava lake inside Chahalé crater. 2006 activity The eruption started during June with the first signs being smoke from the volcano. Rather than being explosive with ash emissions this eruption was more effusive with lave flowing down the side of the mountain. Within a few days the eruption stopped and lava flow stopped before it could reach coastal areas. 2007 Activity Scientists from the KVO reported that an eruption occurred during the evening of 12 January. A local news article noted Moroni residents observing jets of red flames above the summit. An ash plume was observed above the volcano and Aerial observations later in the month showed a lava lake forming within the crater. 2012 Activity Observers in the villages of Mde and Mkazi, on the W flank of Karthala, reported increased incandescence from the summit during the night of 9-10 May. Discussion It is certainly a dangerous volcano, but what perhaps catches my attention is the risk of Lahars and Landslides. Maybe it is just the hotspot contention or the mysterious new volcano created under water near Mayotte. Certainly worth a bit more investigation and conversation.

Introduction My intention is to produce a series of articles (depending on interest) which introduces ideas about volcanic and earthquake activity. I want to go slightly off the beaten track to explore oddities, volcano hazards, analysis methods, Wonders and Mankind’s impacts. Keep in mind I am not expert (corrections gratefully received), but hopefully these will at least give a flavour of some different places in the world and provide a few minutes escape from people’s troubles. Introducing The Salton Sea Buttes Volcanoes Reason for Interest Volcano activity in Southern California tends to escape attention due to the priority concerns with earthquakes. With volcanic activity in the Salton Sea area being younger than originally thought and crustal extension (rifting) being held back by the locked San Andreas Fault the area needs monitoring. The volume of melt material below the area is thought to be very large so we should not assume that future volcanic activity in the area would be quite as benign as it has been till now. This is probably why the USGS now consider this area to be of particular concern. Maybe what really piques my interest is seeing a side to California you don't normally see. The Setting One of the world's largest inland seas and lowest spots on earth at -227 below sea level, Salton Sea was re-created in 1905 when high spring flooding on the Colorado River crashed the canal gates leading into the developing Imperial Valley. For the next 18 months the entire volume of the Colorado River rushed downward into the Salton Trough. By the time engineers were finally able to stop the breaching water in 1907, the Salton Sea had been born at 45 miles long and 20 miles wide and 51 feet deep. In the 1950’s the Salton Sea was the place to vacation for Hollywood stars. The Hollywood influx quickly turned this small vacation getaway into an attraction drawing in 500,000 people a year. Star-filled clubs such as Ace & Spades and the 500 Club sprouted up and recreational boating took off. Many celebrities would come from Los Angeles and down from Palm Springs to take part in the beach life and great water sports offered at Salton Sea. Increasing salinity in the Salton Sea basin has limited the number of types of fish that can be found there, and most fish currently caught are Tilapia. The once-bustling hotels are derelict, broken wooden frames of buildings stand in some spots as other structures are badly decaying with graffiti spray painted over the boarded-up windows and doors. On hot summer days when the temperature can reach up to 120F (48.8C), a pungent Sulphur odor hangs in the air that can be smelled 150 miles away in Los Angeles. Near the Salton Sea can be found Salvation Mountain which Leonard Knight used 30 years of his life and gave up everything to build this colorful masterpiece. In 1984, Leonard was set out to spread the word of the bible and when his truck broke down he starting building Salvation Mountain on the very spot and lived onsite until 2012 when he was moved to a nursing home. Nearby can be found East Jesus a community of artists that live together, create art and party in the desert. The imperial sand dunes to the south of the sea are a 15 mile long and 3 mile wide stretch of 400 foot tall sand dunes. The Dunes have been the home to the tapping of many movies including Stars Wars and is a huge haven for dune buggy enthusiasts. The Date Farms are the most important part of the Salton Sea area’s economy today. Ever since the celebrities and tourists stopped coming in the 1960’s most of the area has become a rundown, dingy area, but the Date Farms have stayed strong. To the North of the Sea is Palm Springs which is like a mini desert Hollywood. Well it’s not quite filled with the high level of stars it was in the 50’s when the Salton Sea was booming but it is still a beautiful place to visit. If you’ve ever wondered what Jurassic-sized palm trees may have looked like then the Anza-Borrego State Park and Palm Canyon is your chance to see. This grove of 100 foot tall bushy palms is crazy. The park is located to the west of the Salton Sea. Joshua Tree National Park is in southeastern California, east of Los Angeles and near Palm Springs and north of the Salton sea it is named after the Joshua trees native to the Mojave Desert. Between San Diego and the Salton sea is the Anza-Borrego Desert State Park. The Tectonic environment The Salton Sea is a large shallow lake located in the central Salton Trough of Southern California. The lake covers the southernmost extension of the San Andreas Fault (SSAF), where the fault takes a southwestward step to the Imperial Fault (IF). The region around the SSAF is actively being stretched due to extensional deformation. Numerous faults, high levels of seismicity and a series of young volcanic buttes suggest this region may be a source for future geohazards. The Salton Trough is an on shore analog to those rift systems in the Gulf of California. It includes the Coachella Valley, Salton Sea, Imperial Valley, and Mexicali Valley from northwest to southeast. The northern Imperial Valley and southern Salton Sea are seismically highly active. Seismicity occurs at 3–8 km depth in the Salton Sea geothermal field at the southeastern shore of the Salton Sea, 3–11 km depth in most of the Brawley Seismic Zone. The entire valley is also characterized by very high heat flow. Brawley Seismic Zone The Brawley Seismic Zone is a north-striking zone of northwest and northeast-striking faults that extends from the southern end of the San Andreas fault to the northern end of the Imperial fault. Across this zone crustal spreading occurs within the transition from the Gulf of California mid-ocean ridge to the San Andreas transform fault. The largest earthquakes to have occurred on the cross-faults were the magnitude 6.2 Elmore Ranch event in 1987. Although the Brawley Seismic Zone activity is clearly proximal to the southern San Andreas fault, the San Jacinto fault zone, and the Imperial fault, the current activity is remaining more than 10 km distant from any of these major faults. Repeated swarms occur in the Seismic zone as rifting occurs but there is no suggestion that these swarms are volcanic in nature. Three times in the last 15 years in 2001, 2009, and 2016, clusters of small earthquakes occurred within a few kilometers distance of the southern terminus of the SAF, within the northern Brawley Seismic Zone at a depth of 3 - 10km. There has been some concern that stress releases in the Brawley Seismic zone could trigger larger earthquakes on the San Andreas fault. The relative likelihood of such an occurrence was considered to be high because the southern SAF ruptured last in a major earthquake more than 320 years ago and the average recurrence rate of large earth-quakes on the southern San Andreas fault is about 180 years. Recent research however suggests that there is likely very little transfer of stress from the Brawley Seismic Zone and to the San Andreas fault. There is however very little research on the impacts to the Brawley Seismic Zone as a result of a significant San Andreas fault earthquake and we are left to guess whether this would lead to enough extension for volcanic activity to initiate again. The Volcano The Salton Buttes are a group of volcanoes in California in the south eastern part of the Salton Sea. They consist of a 7 kilometer long row of five lava domes each no more than 1 kilometer wide. From North to south they are Mullet Island, North Red Hill, South Red Hill, Rock Hill and Obsidian Butte. Obsidian Butte is surrounded by a lava flow, and Mullet Island has a characteristic "onion-skin" foliation with hot springs. The domes were formed by effusive eruptions, but at least Obsidian Butte and South Red Hill also experienced explosive eruptions, which at Obsidian Butte preceded the effusive eruption stage. The lava source for the volcanoes is a magma chamber beneath the Salton Sea, which also heats water for a nearby geothermal plant. These volcanic domes are associated with a local northeast-striking magnetic high that is interpreted to be caused by a magnetic mass, 30 km long, 3 to 12 km wide, and about 4 km thick, with its top buried more than 2 km below the surface. The intrusion under the Salton Sea is thought to be a pluton, an arm or protrusion from a deeply buried molten magma. This intrusion is parallel to the axis of the Salton Trough. Geophysical evidence shows that liquid magma is still present underneath the Salton Buttes. The buttes last erupted between 940 and not 30,000 years ago as previously thought with the U.S. Geological Survey listing the area as a high threat for future blasts. Hot Springs The Hot springs within Salton sea area were known and used by Indians for centuries. The first commercial development in the area dates from the turn of the century, when a therapeutic spa was opened in the foothills of the Chocolate Mountains near Bombay Beach on the east shore of the Salton Sea. This spring is still in use, and is unusual for its high water temperature, ranging from 135 to 180 degrees Fahrenheit. The hot springs are concentrated in a linear pattern along the eastern side of the valley. The line of springs extends from Desert Hot Springs into Mexico, and the arrangement strongly suggests that the warm waters are reaching the surface using fractures of the San Andreas fault system as conduits. There are several experimental geothermal developments in the Imperial Valley, extending from the south shore of the Salton Sea into Mexico. The Salton Sea geothermal field is the largest and the hottest of the several fields in the Salton Valley, and has the longest history of development. The mysterious mud spring Refusing to stay in place, a roiling mass of carbon dioxide and slurry-like soil is migrating across the state at a pace of 20 feet a year. Scientists currently have no real idea why it’s moving or if it can be stopped. Currently located just north of Niland, the mud spring is moving toward Union Pacific Railroad tracks and giving engineers there a headache. A well dug to depressurize the source of the gas had no effect. Steel walls driven 80 feet into the ground were also nonchalantly circumvented; the mud pot simply ducked under them and continued its freakishly linear path of destruction. Mud pots and mud volcanoes generally don’t emit much water, but this one is extremely vigorous, producing somewhere around 40,000 gallons of water a day. This mud spring is close to—but not on—the Wister Fault, a southeastern extension of the San Andreas. However, it appears to be tracing a path that’s at right angles to the region’s major faults. Recent Activity In late August 2005, a swarm of more than a thousand earthquakes between magnitudes 1 and 5.1 occurred at the Obsidian Buttes, near the southern San Andreas Fault. The earthquake swarm shook the nearby town of Brawley with the USGS attributing the temblors to faults in the Brawley Seismic Zone. In September, a sulfurous stench emanated from the Salton Sea and wafted across the Inland Empire. The odor was tentatively linked to a fish die-off, but could also have been caused by volcanic gases. Discussion These are not impressive volcanoes nor is this a glamorous part of California but for me that is exactly why it should be brought to peoples attention. Perhaps the biggest risk here is from earthquakes but there may well be a large source of Magma which would make me nervous.

Introduction My intention is to produce a series of articles (depending on interest) which introduces ideas about volcanic and earthquake activity. I want to go slightly off the beaten track to explore oddities, volcano hazards, analysis methods, Wonders and Mankind’s impacts. Keep in mind I am not expert (corrections gratefully received), but hopefully these will at least give a flavour of some different places in the world and provide a few minutes escape from people’s troubles. Introducing The Robinson Crusoe Island Tsunami Reason for Interest I had never heard of the Juan Fernández Islands or Robinson Crusoe Island but the accounts of the tsunami were so vivid that I thought it was important to remind us that lives can be devastated by disaster. Throw in a little mythical history and I find it fascinating. The Island Robinson Crusoe Island is the second largest of the Juan Fernández Islands, situated 670 km west of San Antonio Chile. It is the most populated of the islands with most living in the town of San Juan Bautista at Cumberland Bay on the north coast. From 1704 to 1709, the island was home to the marooned sailor Alexander Selkirk, who at least partially inspired novelist Daniel Defoe's fictional Robinson Crusoe in his 1719 novel. Robinson Crusoe Island lies to the west of the boundary between the Nazca Plate and the South American Plate. A volcanic eruption on the island was reported in 1743 from El Yunque, but this event is unconfirmed. The Fuerte Santa Barbara fort once used by 18th century Spanish to protect themselves from raucous pirates. The islands have a subtropical Mediterranean climate moderated by the cold Humboldt Current, which flows northward to the east of the islands, and the southeast trade winds. Temperatures range from 10 °C to 22 °C. In 1977 the archipelago was named a biosphere reserve and now forms part of the enormous Juan Fernandez Marine Park. A particular success has been the South American fur seal, a species that was almost extinct 40 years ago, which now has a population of 30,000 on the islands. Just offshore in the harbour can be found the wreck of the German light cruiser SMS Dresden. Having escaped the battle of the Falklands she eluded her British pursuers until she put into Robinson Crusoe Island in March 1915. Her engines were worn out and she had almost no coal left for her boilers. After The British violated Chilean neutrality and opened fire on the ship the Germans scuttled the Dresden and the majority of the crew escaped. The Tectonic environment The west coast of South America is a subduction zone where the Nazca Plate is plowing under the South America Plate at an average rate of 3 inches per year. The boundary where the two plates converge is marked by a trench located about 62 miles offshore where the Nazca Plate begins its descent beneath the South America Plate. When plates become locked together for a time and earthquake may occur as the plates lurch past each other violently. If this occurs at a subduction zone then crust one side of the earthquake will drop and on the other rise and it is this movement that causes a tsunami. A First hand Account British couple Rhian Salmon and Andy Whittaker embarked on the trip of a lifetime in their yacht. Their first port of call was the volcanic paradise of Robinson Crusoe Island where they moored near to the village of San Juan Bautista. The island is part of the Juan Fernández Islands 400 miles off the South American coast. In the early hours of 27 February, the day they were due to set sail again, a devastating earthquake struck Chile, and unleashed a massive tsunami westwards across the Pacific directly towards the island. At 4am they work up to the sound of water rushing under the boat. Then they heard an almighty roar resonating around the bay. Water is flying past the yacht in big whirls, carrying trees and what looks like roofs. The water sweeps back towards the open ocean carrying with it all objects in its path. They hear cries and calls from people on the roofs and trapped in the houses which fly past them. Andy reaches over the side and pulls a boy on to the deck shivering, covered in oil and cuts, looking for his family. They are surrounded by strong fuel fumes and there is a strong noise of gas hissing from gas bottles that have been ripped from the houses they used to supply. Another older boy climbs on board. There are other boats in the water now and a Navy boat. The Navy boat is unoccupied and dragging hard on its mooring. Andy and the two boys fend of the boat off while on the other side a rooftop is pushing up against us, and next to it a whole house. Further away, a family are stranded on the top floor of a floating house. They see the yacht and start to swim. Andy throws a rope to them and they grab on. Andy pulls up a young girl but the other three are swept away. As dawn approaches they start to see the damage. The whole town front has been wiped out, the navy boat is wrecked on the rocks, the shops where they bought supplies is gone, as are the school and town square. The Maule Chile Earthquake The 2010 Chile Maule earthquake occurred off the coast of central Chile on a Saturday in the early hours of the morning. The magnitude of the earthquake was recorded as 8.8 on the moment magnitude scale, with intense shaking lasting for nearly four minutes. Since the earthquake was in the middle of the night on a weekend injury due to falling damaged infrastructure like bridges and roads was minimized. The tsunami waves that followed this event affected the coastal regions between the cities of Valparaiso and Valdivia, with minor effects as far as Coquimbo. In Chile 525 people lost their lives, 25 people went missing and about 9% of the population in the affected regions lost their homes. The focus of the earthquake occurred at a depth of about 22 miles below the surface of the Pacific Ocean. The earthquake—resulting from the rupture of a 300- to 375-mile stretch of the fault that separates the South American Plate from the subducting Nazca Plate. Stress brought on by the convergence of the two tectonic plates caused rocks to shatter along the boundary between them. This forced a portion of the seabed upward, displacing the water above and triggering a tsunami. The Chilean town of Constitución was inundated by waves as high as 50 feet and the port of Talcahuano was damaged by a wave measuring nearly 8 feet high. Traveling across the Pacific Ocean at nearly 450 miles per hour the tsunami encountered the Robinson Crusoe Island approximately 420 miles off the coast of Chile. The tremor shook the capital Santiago for a minute bringing down telephone and power lines. Santiago's international airport was forced to close, a highway bridge collapsed and rubble from damaged buildings fell on to the streets. The largest earthquake ever recorded struck the same area of Chile on 22 May 1960. The magnitude 9.5 quake killed 1,655 people and left 2 million homeless, and caused a tsunami that killed people in Hawaii, Japan and the Philippines. Several factors contributed overall to the low casualty rate and rapid recovery. A major factor was the strong building code in Chile and its comprehensive enforcement. A second factor was the limited number of fires after the earthquake due to the shut down of the electricity grid early in the earthquake. Third factor was the practiced close coordination between emergency management teams. Discussion While an earthquake of the same magnitude in the same area is unlikely there will be other earthquakes along the fault line in the future. History suggests the next one could be even bigger and reach right across the Pacific ocean.