The 2012 Negros earthquake occurred on February 6 at , with a
body wave magnitude Body-waves consist of P-waves that are the first to arrive (see seismogram), or S-waves, or reflections of either. Body-waves travel through rock directly.
mB scale
The original "body-wave magnitude" – mB or mB (uppercase "B") – was developed ...
of 6.7 and a maximum intensity of VII (''Destructive'') off the coast of
Negros Oriental
Negros Oriental ( ceb, Sidlakang Negros; tl, Silangang Negros), officially the Province of Negros Oriental, is a province in the Philippines located in the Central Visayas region. Its capital is the city of Dumaguete. It occupies the southeaste ...
,
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
. The epicenter of the
thrust fault
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks.
Thrust geometry and nomenclature
Reverse faults
A thrust fault is a type of reverse fault that has a dip of 45 degrees or less.
If ...
earthquake
was approximately north of Negros Oriental's provincial capital,
Dumaguete
Dumaguete, officially the City of Dumaguete ( ceb, Dakbayan sa Dumaguete; fil, Lungsod ng Dumaguete), is a 3rd income class component city and the capital of the province of Negros Oriental, Philippines. According to the 2020 census, it has a p ...
.
Earthquake
The recorded intensities according to the Philippine Institute of Volcanology and Seismology (PHIVOLCS) on the Earthquake Intensity Scale (PEIS) were VII in
Dumaguete
Dumaguete, officially the City of Dumaguete ( ceb, Dakbayan sa Dumaguete; fil, Lungsod ng Dumaguete), is a 3rd income class component city and the capital of the province of Negros Oriental, Philippines. According to the 2020 census, it has a p ...
and V in
Cebu
Cebu (; ceb, Sugbo), officially the Province of Cebu ( ceb, Lalawigan sa Sugbo; tl, Lalawigan ng Cebu; hil, Kapuroan sang Sugbo), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 ...
.
The earthquake was felt as far as
Mindanao
Mindanao ( ) ( Jawi: مينداناو) is the second-largest island in the Philippines, after Luzon, and seventh-most populous island in the world. Located in the southern region of the archipelago, the island is part of an island group of ...
in the provinces of
Misamis and
Lanao as well as
Iligan
Iligan, officially the City of Iligan ( ceb, Dakbayan sa Iligan; fil, Lungsod ng Iligan; Maranao: ''Inged a Iligan''), is a 1st class highly urbanized city in the region of Northern Mindanao, Philippines. According to the 2020 census, it has ...
.
Geology
The
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
lies within the
Pacific Ring of Fire
The Ring of Fire (also known as the Pacific Ring of Fire, the Rim of Fire, the Girdle of Fire or the Circum-Pacific belt) is a region around much of the rim of the Pacific Ocean where many Types of volcanic eruptions, volcanic eruptions and ...
, 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 warning
The
Philippine Institute of Volcanology and Seismology
The Philippine Institute of Volcanology and Seismology (PHIVOLCS, ; tl, Surian ng Pilipinas sa Bulkanolohiya at Sismolohiya) is a Philippine national institution dedicated to provide information on the activities of volcanoes, earthquakes, and ...
(PHIVOLCS) issued a level two
tsunami
A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explo ...
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
Negros Oriental ( ceb, Sidlakang Negros; tl, Silangang Negros), officially the Province of Negros Oriental, is a province in the Philippines located in the Central Visayas region. Its capital is the city of Dumaguete. It occupies the southeaste ...
from
San Jose to
Vallehermoso Vallehermoso can mean:
*Vallehermoso, Negros Oriental, a municipality in the Philippines
*Vallehermoso, Santa Cruz de Tenerife, a municipality on Canary Island
*Vallehermoso (Madrid), a ward of Chamberi district, Madrid, Spain
*Estadio de Valleherm ...
, and on the western side of
Cebu
Cebu (; ceb, Sugbo), officially the Province of Cebu ( ceb, Lalawigan sa Sugbo; tl, Lalawigan ng Cebu; hil, Kapuroan sang Sugbo), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 ...
from
Badian to
Barili
Barili, officially the Municipality of Barili ( ceb, Lungsod sa Barili; tgl, Bayan ng Barili), is a 2nd class municipality in the province of Cebu, Philippines. According to the 2020 census, it has a population of 80,715 people.
History
The w ...
were also reported to have been affected by the tsunami, though no widespread damage was reported.
"Chona Mae" hoax
In
Cebu City
Cebu City, officially the City of Cebu ( ceb, Dakbayan sa Sugbo; fil, Lungsod ng Cebu; hil, Dakbanwa sang Sugbo), is a 1st class Cities of the Philippines#Legal classification, highly urbanized city in the Central Visayas Regions of the P ...
, 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
Panic is a sudden sensation of fear, which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reactio ...
. This is despite the fact that Cebu City, being on the eastern side of Cebu island, is opposite to the side facing
Negros
Negros is the fourth largest and third most populous island in the Philippines, with a total land area of . Negros is one of the many islands of the Visayas, in the central part of the country. The predominant inhabitants of the island region a ...
, 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
The occurred at 14:46 JST (05:46 UTC) on 11 March. The magnitude 9.0–9.1 (M) undersea megathrust earthquake had an epicenter in the Pacific Ocean, east of the Oshika Peninsula of the Tōhoku region, and lasted approximately six minutes ...
and its effects in
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...
, was also attributed as a factor to the panic.
Some residents of
Dumaguete
Dumaguete, officially the City of Dumaguete ( ceb, Dakbayan sa Dumaguete; fil, Lungsod ng Dumaguete), is a 3rd income class component city and the capital of the province of Negros Oriental, Philippines. According to the 2020 census, it has a p ...
also scrambled to the mountain town of
Valencia
Valencia ( va, València) is the capital of the Autonomous communities of Spain, autonomous community of Valencian Community, Valencia and the Municipalities of Spain, third-most populated municipality in Spain, with 791,413 inhabitants. It is ...
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
The degree and extent of damage caused by the earthquake was significant, with most of the damage sustained during the initial earthquake. The towns that experienced the most damage were the towns of
Tayasan,
Jimalalud
Jimalalud, officially the Municipality of Jimalalud ( ceb, Lungsod sa Jimalalud; tl, Bayan ng Jimalalud), is a 4th class municipality in the province of Negros Oriental, Philippines. According to the 2020 census, it has a population of 32,256 pe ...
,
La Libertad, and the city of
Guihulngan
Guihulngan, officially the City of Guihulngan ( ceb, Dakbayan sa Guihulngan; fil, Lungsod ng Guihulngan), is a 5th class component city in the province of Negros Oriental, Philippines. According to the 2020 census, it has a population of 102,656 ...
, in
Negros Oriental
Negros Oriental ( ceb, Sidlakang Negros; tl, Silangang Negros), officially the Province of Negros Oriental, is a province in the Philippines located in the Central Visayas region. Its capital is the city of Dumaguete. It occupies the southeaste ...
. Several houses and buildings collapsed, while others sustained more minor damage. The earthquake also triggered numerous landslides which buried houses and people, including in the areas of Barangay Solongon,
La Libertad and Planas,
Guihulngan
Guihulngan, officially the City of Guihulngan ( ceb, Dakbayan sa Guihulngan; fil, Lungsod ng Guihulngan), is a 5th class component city in the province of Negros Oriental, Philippines. According to the 2020 census, it has a population of 102,656 ...
.
Telecommunication services were disrupted after the earthquake.
Water
Water was cut off in several places, primarily the isolated remote towns.
Guihulngan
Guihulngan, officially the City of Guihulngan ( ceb, Dakbayan sa Guihulngan; fil, Lungsod ng Guihulngan), is a 5th class component city in the province of Negros Oriental, Philippines. According to the 2020 census, it has a population of 102,656 ...
, one of the cities affected by the earthquake, suffered extensive damage. Its water services, along with electricity and telecommunications, were reported to be cut off.
Electricity
After the initial earthquake, the power supply was suddenly disrupted in affected areas after power lines were damaged. Power plants in Visayas tripped or shut down following the earthquake, although no major damage was sustained in transmission facilities. On February 8, power was restored in some areas.
Transport
The transport network of some parts of
Cebu
Cebu (; ceb, Sugbo), officially the Province of Cebu ( ceb, Lalawigan sa Sugbo; tl, Lalawigan ng Cebu; hil, Kapuroan sang Sugbo), is a province of the Philippines located in the Central Visayas region, and consists of a main island and 167 ...
and
Negros Oriental
Negros Oriental ( ceb, Sidlakang Negros; tl, Silangang Negros), officially the Province of Negros Oriental, is a province in the Philippines located in the Central Visayas region. Its capital is the city of Dumaguete. It occupies the southeaste ...
suffered severe disruptions. Main arterial roads were damaged, although automobiles and people could still pass through. A small number of roads, especially in the mountainous territories, were thought to be destroyed. A total of three roads and ten bridges were destroyed. Because of damage to roads and bridges, access to some remote villages was no longer possible. Most of the damage experienced was in north Negros Oriental, which is more mountainous than the rest of Negros Oriental.
Cultural and governmental properties
Among the properties destroyed by the earthquake were the public market and the courthouse of
Guihulngan
Guihulngan, officially the City of Guihulngan ( ceb, Dakbayan sa Guihulngan; fil, Lungsod ng Guihulngan), is a 5th class component city in the province of Negros Oriental, Philippines. According to the 2020 census, it has a population of 102,656 ...
. The Aglipay Church in
La Libertad also collapsed.
See also
*
List of earthquakes in 2012
This is a list of earthquakes in 2012. Only earthquakes of magnitude 6 or above are included, unless they result in damage or casualties, or are notable for some other reason. All dates are listed according to UTC time. Two huge 8 magnitude ear ...
*
2013 Bohol earthquake
The 2013 Bohol earthquake occurred on October 15 at in Bohol, an island province located in Central Visayas, Philippines. The magnitude of the earthquake was recorded at 7.2, with epicenter of Sagbayan, and its depth of focus was . It affe ...
*
List of earthquakes in the Philippines
The Philippines lies along the Pacific Ring of Fire, which causes the country to have frequent seismic and volcanic activity. Many earthquakes of smaller magnitude occur very regularly due to the meeting of major tectonic plates in the region. T ...
References
External links
*
*
{{Earthquakes in the Philippines
Visayas earthquake
2012 disasters in the Philippines
History of Cebu
Earthquakes in the Philippines
2012 in the Philippines
History of Negros Oriental
February 2012 events in the Philippines
Buried rupture earthquakes