The 1993 Lovian earthquake, also known as the 1993 Peace Island earthquake, or the Great Quake of Sylvania, was a magnitude-7.7 earthquake that occurred on the morning of July 23, 1993, 63 miles (101 km) off the coast of Sylvania. Lasting for approximately 6 minutes and 23 seconds, the powerful thrust earthquake caused an 8-meter (26ft)-high tsunami, which devastated parts of Noble City and much of its immediate vicinity; and was felt as far north as Newhaven and Sofasi.
Although up to 35% of Noble City's buildings were leveled by the initial shaking, mainly historical buildings that were not built to meet earthquake codes, the vast majority of the damage and death toll resulted from the tsunami. In total, 1,200 people were killed in Sylvania and 380 were killed in Oceana, with many more remaining unaccounted for in both states. A total of 15,600 people lost their homes and livelihoods across Peace Island. In some particularly low-lying areas, the wave penetrated as far as 10 kilometers (6 miles) inland, devastating local infrastructure even further with major roads and rail lines being washed away. The earthquake is often regarded as the worst natural disaster in Lovian history, and has resulted in insured losses of $680 million (1993 USD) and a 3% slump in economic output leading into 1994.
The 2006 disaster film Tension is based on the events, as is the 2017 film As the Earth Crumbles.
Earthquake[]
The main earthquake occurred at approximately 6:13 AM (UTC-9) on July 23, 1993, at a depth of 20 miles (32 km); its epicenter was located 63 miles (101 km) to the immediate south of Noble City and 72 miles (115 km) south-southeast of Hurbanova. It was initially reported as a 6.9Mw by the United States Geological Survey (USGS) but was quickly upgraded to a 7.7Mw by the Lovian Geological Center (LGC), with seismic waves propagating outwards in all directions. With the relatively small size of the Lovian Boundary Fault in mind, the earthquake and its effects were largely confined to its immediate vicinity, but "some minor shaking" was registered as far as Santa Clarita, California.
Several smaller foreshocks occurred in the days and hours prior to the quake, the largest one—a magnitude 4.7—occurring due south of the hamlet of Skelington, Oceana, 40 kilometers (25 miles) from Noble City. Some minor damage and injuries were reported in the area, but owing to the geographical isolation and sparsely-populated nature of the region, no deaths occurred. Further minor foreshocks were reported north of Dien Village before a sudden lull in tectonic activity leading into July 23. The main earthquake began suddenly, with seismic waves reaching Lovian shores approximately 96 seconds into the event. A tsunami was generated with peak wave heights of 33 feet (10.1 meters) in isolated areas; the wave that hit Noble City was 26 feet (7.9 meters) tall, and came ashore in the immediate aftermath of the earthquake. Tsunami watches were issued along the North American west coast but by the time the wave reached American and Canadian shores it was only 3-7 feet (1-2 meters) tall, the majority of its energy having dissipated with time.
Aftershocks followed the earthquake for several years, before tapering off completely by 1997. The largest recorded aftershock occurred on July 9, 1994, almost an entire year later. and measured at 6.9 on the Richter scale. Occurring south of Dien Village, the aftershock caused moderate damage to the surrounding area and was strong enough to briefly spark fears among some residents that another “big one” was on its way, even as Noble City rebuilt.
Geology[]
Seismic activity in Lovia is frequent owing to the archipelago’s proximity to the Pacific Ring of Fire. Thousands of earthquakes are recorded in this location every year, though the vast majority are too small to be felt without the aid of specialized instruments; it is estimated that a "big one" the size of the 1993 earthquake occurs once every 78 years on average, with the last earthquake of similar magnitude to hit Lovia being the 1903 earthquake.
In 1987, Nobel University researchers estimated that the likelihood of an earthquake the size of the 1903 quake or greater occurring in the following decade was as high as 89-97%, with the 78-year time gap having long passed. Geologically, the 1903 and 1993 events were very similar, and a similar subduction mechanism was at play for both despite the differing fault lines. In the case of the 1993 earthquake, vast amounts of energy that had built up in the subduction zone over time were suddenly released along the entire length of the Lovian Boundary Fault (approximately 300 kilometers, or 190 miles).
Tsunami[]
The energy released by the earthquake resulted in the formation of a major tsunami wave roughly 8 meters (26ft) high, which propagated across the Pacific Ocean at speeds of up to 500 miles per hour (800 km/h) and brought major devastation to the Lovian archipelago. The tsunami affected all areas along the North American western seaboard and as far as Hawaii, but by the time it reached American and Canadian shores it had lost most of its momentum.
The south coast of Peace Island was hit at approximately 6:21 AM (UTC-9), 8 minutes after shaking first commenced. Amid a brief lull in the earthquake, the wave came ashore on Oceana Beach, lapping around the shoreline and tracing the coast up towards Noble City. Skelington, Bardeyow, and Dien Village were among the first settlements to be hit, with floodwaters following the course of the Dien River and reaching heights of up to 7 meters (23 feet) in isolated areas; though due to the sparsely-populated nature of the area the immediate death toll was only six people.
The wave hit Noble City at approximately 6:30 AM (UTC-9), with news helicopter footage of the disaster showing water drawing back into Noble City Bay prior to the moment of impact and the sea floor being momentarily exposed as a result. The wave struck King's Gardens first before swamping other areas of the city, flooding up to 80% of its total land area and reaching approximately 10 kilometers (6 miles) inland in some particularly low-lying areas of the floodplain. In total, 70 square kilometers (27 square miles) of Noble City were inundated under as much as 8 meters (26ft) of water, and with it being the morning rush hour at the time the quake hit 780 people lost their lives when their vehicles were swept away in gridlocked traffic. News footage also showed the wave crashing over Old Highway 1, sweeping away cars, trucks and buses in an instant before striking the end of the airport's runway.