Kanlaon

Basic Marker – Red color used for difficult or summit trails

In 2016, first three hiking trails have been marked, with additional and more extensive trails added in 2017 from the center of the Guintubdan village including a trail to the top. The works have been implemented by the Mendel University, in cooperation with De La Salle University Bacolod and DENR. The project has been financed by the Embassy of the Czech Republic in Manila in the framework of Czech Aid Development program.[5] Three color-coded trails using the colors of the Philippine flag were opened:

Left Turn Marker on a blue trail – marker showing the change of direction of the trail

• Red Trail from Guintubdan to Buslugan Falls (marked in 2016)
• Yellow Trail from Guintubdan to Oro Falls (marked in 2016)
• Blue Trail from Guintubdan to Salas Park new Pavilion (marked in 2016)
• Red Trail from Guintubdan to Mt. Kanla-On Summit (marked in 2017)
• Adventure Trail and additional new trails (marked in 2017)

This system uses three bars – usually one color in between two white bars,[6] with different meanings attached to different colors: red indicates the most difficult or summit trails,[7] blue for difficult trails and yellow and green for easy or interconnecting trails. These marks may be posted on wooden boards or metallic plates. Basic trail markers are square, 10x10 cm in size. The volunteers marking these trails usually prepare sheet metal or cardboard matrices to keep the signs uniform in size. Any change of direction is marked with arrows of the same color and similar design.

On August 10, 1996, 24 mountain climbers hiked the volcano when Kanlaon erupted without warning, killing British student Julian Green and Filipinos Jamrain Tragico and Neil Perez, who were trapped near the summit close to the crater. The local authorities rescued 17 others, including 10 Belgians, another British climber and six Filipinos while Edwin Ematong, a member of the Negros Mountaineering Club Inc. and who, along with his cousin Neil Perez, guided the British Nationals survived the eruption, having descended the volcano ahead of his group.

One of the rescued Belgians, Caroline Verlinde, said she and her group were about to leave a site near the crater rim when suddenly the volcano ejected ash, stones and hot gas. She ran to a tree for cover and saw her friends being hit by falling hot tephra. She said their Filipino guide told them the smoke billowing out from the crater "was just ordinary."[8][9][10]

PHIVOLCS noted in a March 22 report that since January, earthquake clusters or occurrences had been recorded by the seismic monitoring network around the volcano. These earthquakes might had signified a reactivation of the volcanic system at depth and could be a precursor to more vigorous activity, such as ash explosions. This interpretation was based on similar earthquake clusters manifested prior to the 1996 phreatic explosion from the active summit crater of the volcano. In view of the possibility of a sudden ash ejection, PHIVOLCS recommended the immediate suspension of all treks to the summit crater until further notice.

An increase in seismic activity during February to April was followed by raising alert on the volcano. An ash eruption occurred on November 28.

On March 17, a gray plume was observed above Kanlaon. Small eruptions produced plumes that rose 100 meters (330 ft) above the crater of the volcano. A total of 46 minor ash ejections were recorded. After July 23, only weak emission was noted and seismic activity returned to normal.

A brief phreatic ash eruption occurred on January 21, producing a 500 meters (1,600 ft) high ash plume. A fine layer of ash fell on the town of Cabagnaan 5.5 kilometers (3.4 mi) SW of the crater. Ash emissions began again on March 20 and caused minor ash fall in the municipality of Guintubdan 5-kilometer (3.1 mi) W of the volcano. Until April 4, occasional ash eruptions reached 1 km above the volcano, and small ash fall was reported in the municipalities of La Castellana (16 kilometers (9.9 mi) SW of the crater), Upper Sag-ang, Yubo (5–6 kilometers (3.1–3.7 mi) SW), and Guintubdan (5–6 kilometers (3.1–3.7 mi) WNW). Ash eruptions stopped after May 25.

On June 3, Kanlaon again exhibited restiveness and spewed steam and ash. Alert Level 1 was issued on June 12. Until July 25, a total of 23 ash eruptions were reported. All eruptions were phreatic (i.e. no fresh magma was ejected), and ejected ash and steam up to 2 km (1.2 mi) above the crater. No significant seismic activity had occurred before or after the ash emissions, indicating the explosions were near surface hydrothermal events.

On February 10, PHIVOLCS issued an alert stating that the seismic network at Kanlaon recorded a total of 21 low frequency volcanic earthquakes (LFVQ) during the past 24 hours. Due to the increasing number of recorded volcanic earthquakes, PHIVOLCS raised Kanlaon Volcano's alert status from Alert Level 0 to Alert Level 1, which means the volcano is at slightly elevated unrest and volcanic activity could lead to steam and ash ejections.[11] A 4-kilometer (2.5 mi) Permanent Danger Zone (PDZ) was maintained around the volcano, as sudden explosions may occur without warning, but no eruptions occurred.

From August 23 to September 1, 257 volcanic earthquakes were recorded. Epicenters of the recorded quakes were clustered at the north-west slope which may indicate movement of an active local fault at the slope induced by pressure beneath the volcano. Surface observations did not show any significant change in the steam emission from the crater. PHIVOLCS maintained the alert status at Level 0.[12]

On November 23, Kanlaon had a small, steam-driven explosion. PHIVOLCS raised the alert level to 1 (mild restiveness). On December 12, Kanlaon had two low energy ash eruptions. The minor ash eruption of the volcano reached as high as 984 ft (300 m). On December 27, an ash eruption occurred at Kanlaon's active crater. The eruption plume reached as high as 3,281 ft (1,000 m). Light ashfall were reported in some barangays near Kanlaon Volcano.

On March 29 at 6:20 pm, Kanlaon erupted for 12 minutes which produced a volcanic plume 1,500 m (4,900 ft) above the crater and a "booming sound" was heard in some barangays near the volcano. According to the police department of Canlaon, several fire balls, which were coming from the crater of the volcano, started to flow following a booming sound and causing a bush fire. PHIVOLCS issued alert level number 1. No casualties were reported.[13]

On March 11, PHIVOLCS raised the volcano's alert level from 0 to 1 due to its abnormal activities since March 9. 80 volcanic earthquakes were plotted since then.[14] On June 21, the volcano showed some signs of increased unrest. By June 22, the volcano's activity continued, with a series of tectonic earthquakes ranging from M3.2 to M4.7. A total of 278 earthquakes was observed for a 72-hour period (from June 21, 8AM – June 24, 8AM), possibly related to the magmatic activity underneath the volcano. Earthquakes continued, with steam and fumarolic activity rising 200–300 meters above. PHIVOLCS reminded the public to stay away to the 4-km PDZ (Permanent Danger Zone) around the volcano, as abnormal conditions and sudden phreatic explosions might occur. [15] [16] [17]