At about 10am on March 7, 2011 (UTC+8), a loud explosion was heard at the island of Tablas in Romblon province in Central Philippines. It was followed by a tremor.
Fishermen on sea saw a fiery and swift ball of fire falling from sky (daytime).[3]
Volcanic eruptions
Pre-history
Most of the Eruption recorded from potentially active Stratovolcano according to dated Lava flows .
There are no cultural records of historical eruptions. However, weak steaming is currently present in some of the heavily eroded vents on the North Western side of the summit. The ancient eruptions were said to have caused the formation of a Lava Dome on the Western Slopes of the mountain known as White Rock which makes a nice tourist destination and is usually a field trip destination for students of Pampanga Agricultural College. The Arayat amphitheatre is said to have been caused by the summit's collapse on the western side but a much deeper crater is present on the eastern side, it was said that the mountain was once a volcanic island, until eruptions covered the surrounding area with soil, eruptions were said to be the possible cause of a theorized re-route of Pampanga River which is said to have once passed on the western side rather than eastern side where it currently moves[4]
There are no historical eruptions within the Natib caldera complex. Studies in 1991 (Panum and Rayem) indicate that the last eruptive activity was probably Holocene to upper Pleistocene. An earlier study in 1971 (Ebasco Services) dated the eruptive products between 69,000 +/- 27,000 years old.
There are no historical eruptions from the volcano with the last eruptive activity dated as Holocene as reported by the Global Volcanism Program. Thick lava flows from that period are present on the flanks of Mount Masaraga, an understudied volcano in the Philippines.
The caldera, whose lake surface is only 1m above sea level, may have formed by least two major eruptions of about 1 million and 27,000-29,000 years ago.[4]
The activity of Ancestral Pinatubo seems to have begun about 1.1 million years ago and probably ended tens of thousands or more before the birth of 'Modern Pinatubo'. Much of the rugged land surrounding the present volcano consists of remnants of 'ancestral' Pinatubo. It was an andesite and dacitestratovolcano with its eruptive activity much less explosive than modern Pinatubo.
There are no recorded historical eruptions from Mariveles caldera, with the last activity indicated by Radiocarbon dating occurring around mid-Holocene or about 2050 BCE.[6]
Historical era
Eruptions have also destroyed numerous lakeside towns, burying them with volcanic ash or submerged them by rising lake waters displaced by the erupted material. Lipa, Taal, Sala, Bauan and Tanauan were formerly located along Taal Lake. Presently, only three towns are on the lake's shore. Remnants of the old lakeside towns are reported to be seen under the lake's waters.[9]
There was a scare in 1995 but PHIVOLCS investigation at the time did not disclose any unusual activity, and no unusual activity has been reported since.
The most destructive eruption of Mayon occurred on February 1, 1814 (VEI=4). Lava flowed but not as much compared to the 1766 eruption; Instead, the volcano was belching dark ash and eventually bombarded the town of Cagsawa with tephra that buried it. Trees were burned; rivers were certainly damaged. Proximate areas were also devastated by the eruption, with ash accumulating to 9 m (30 ft) in depth. In Albay, a total of 2,200 locals perished in what is considered to be the most lethal eruption in Mayon's history; estimates by PHIVOLCS list the casualties at about 1,200, however. The eruption is believed to have contributed to the accumulation of atmospheric ash,[citation needed] capped by the catastrophic eruption of Mount Tambora in 1815, that led to the Year Without a Summer in 1816.
Reawakened in 1990 producing the 2nd largest eruption in the 20th century. Followed by milder eruptions in 1992 and 1993,On July 16, 1990, the major 1990 Luzon earthquake of magnitude 7.7 struck central Luzon. This was the largest earthquake recorded in 1990,[10]
The most active volcano in central Philippines, Kanlaon has erupted 26 times since 1919. Eruptions are typically phreatic explosions of small-to-moderate size that produce minor ash falls near the volcano. In 1902, the eruption was classified as strombolian, typified by the ejection of incandescentcinder, lapilli and lava bombs.
Bulusan is generally known for its sudden steam-driven or phreatic explosions. It has erupted 15 times since 1885 and is considered as the 4th most active volcano in the Philippines after Mayon, Taal, and Kanlaon, There are evacuation procedures in place for parts of the peninsula, the farms nearest the volcano are evacuated, and many of the village schools are closed if it is considered possible that a more destructive eruption could occur.
On February 16, 1871, earthquakes and subterranean rumblings began to be felt on the island, which increased in severity until April 30 when a volcanic fissure opened up 400 yards southwest of the village of Catarman, on the northwest flank of Hibok-hibok Volcano. From the opening, lava was continuously ejected and poured into the sea for four years destroying the town. At the same time, the vent started gaining in height and width thus forming Mt. Vulcan. In 1875, the Challenger expedition visited the area, and described the mountain as a dome, about 1,950 feet (590 m) in height, without any crater, but still smoking and incandescent at the top.[11]
Earthquakes
Pre-history
There are no recorded of events nor few about earthquake before the History was written, but it would be possibly caused by collision of Tectonic Plates and Volcanic Eruptions, resulting to an earthquakes, and forming another Mountains , Volcanoes and even Lakes.
For example, the Taal Volcano, This is a part of a chain of volcanoes along the island of Luzon, which were formed by two tectonic plates colliding over 500,000 years ago. Since the formation of this large caldera, subsequent eruptions created another volcanic island, within Taal Lake, known as Volcano Island.[12]
Historical era
The table below is a tally of the ten most deadly recorded earthquakes in the Philippines since the 1600s with having the most number of casualties:
18th century
An intensity VII struck Lake Bombon (now known as Taal Lake) on September 24, 1716. It was connected with the eruption of Taal volcano; the constant volcanic activity in the area of Taal caused seismic movements.
An intensity IX struck Tayabas (now known as Quezon) in 1730. It had ruined the churches and convent in Mauban and several other churches in the province of Tayabas and Laguna.
19th century
An earthquake on June 3, 1863, destroyed the Manila Cathedral, the Ayuntamiento (City Hall), the Governor's Palace (all three located at the time on Plaza Mayor, now Plaza de Roma) and much of the city. The residence of the Governor-General was moved to Malacañang Palace located about 3 km (1.9 miles) up the Pasig River, while the other two buildings were rebuilt in place.
An intensity X struck Luzon on July 14–24, 1880.[13] The quake caused severe damage to these major cities in Luzon, most significantly in Manila where a lot of buildings collapsed. Number of casualties are unknown.[14]
A quake struck Lucban, Quezon on October 26, 1884. It destroyed churches in Lucban town in Quezon province and Cavinti town in Laguna province.[14]
Ten deadliest recorded earthquakes in the Philippines since the 1600s
Extinctions might be caused by natural calamities, like climate changes, astronomical events, volcanic eruptions, earthquakes, wild fires, floods, and human hunting activities.