The recorded intensities according to the Philippine Institute of Volcanology and Seismology (PHIVOLCS) on the Earthquake Intensity Scale (PEIS) were VII in
Dumaguete and V in
Cebu. The earthquake was felt as far as
Mindanao in the provinces of
Misamis and
Lanao as well as
Iligan.
Geology The
Philippines lies within the Pacific
Ring of Fire, which results in the archipelago experiencing frequent volcanic and seismic activity. The strongest earthquake to hit Negros occurred in 1948, but did not cause any damage. According to PHIVOLCS, the earthquake was caused by movement on a previously undiscovered
fault. However, according to an Environmental Sciences professor, this fault was already known to private geologists hired by the Negros Occidental government to create a land use map for the province.
Tsunami The
Philippine Institute of Volcanology and Seismology (PHIVOLCS) issued a level two
tsunami alert, indicating that the public should be alert for "unusual waves", but no formal evacuation orders were issued. Tsunami waves reported to be as high as were reported to have struck Barangays Martilo, Pisong, and Magtalisay in
La Libertad. Coastal areas on the eastern seaboard of
Negros Oriental from
San Jose to
Vallehermoso, and on the western side of
Cebu from
Badian to
Barili were also reported to have been affected by the tsunami, though no widespread damage was reported.
"Chona Mae" hoax In
Cebu City, rumors that a tsunami had hit the coastal villages of Ermita, Mambaling, and Pasil, with some reports saying that the tsunami had reached as far as Barangay Lahug, forced residents into a
panic. This is despite the fact that Cebu City, being on the eastern side of Cebu island, is opposite to the side facing
Negros, the epicenter of the earthquake, and could not have been hit by a tsunami from the earthquake. The ensuing panic forced many businesses, schools, and offices in Cebu City to close for the day. Residents fled to the mountainous areas of the city, all the way up to Barangay Busay, more than away from downtown Cebu City. The cause of the panic was credited to, anecdotally, have come from someone who was calling out for someone named "
Chona Mae", which eventually morphed mistakenly into a cry for "tsunami". The earthquake, which happened nearly a year after the
2011 Tōhoku earthquake and tsunami and its effects in
Japan, was also attributed as a factor to the panic. Some residents of
Dumaguete also scrambled to the mountain town of
Valencia also because of rumors of a tsunami, which were later confirmed to be false. PHIVOLCS issued the
tsunami alert at 14:30
PST, however no tsunami followed. ==Damage and effects==