Cover Design by: Arnold A. Villar Printed & Produced by: PHIVOLCS Publication Copyright: DOST – PHIVOLCS 2003 The ash ejection on 05 April induced related damage in the of the Philippines” under a manned seismic stations. To rose to 1.5 km and deposited province. The earthquake was grant-aid of the Japan Interna- ensure continuity of providing traces of ash in the downwind associated with an 18-km long tional Cooperation Agency basic S & T services should HH iigghhlliigghhttss areas near the crater. On 7 ground rupture onland, which (JICA). The said JICA project the PHIVOLCS main office October, a faint crater glow, transected several barangays is now in its Phase II of im- operation be disrupted in the which can be seen only with of Dimasalang, Palanas and plementation. For volcano future, a mirror station has Two volcanoes, Kanlaon continued for months that a the use of a telescope or night Cataingan. The team verified monitoring, it involves installa- been established in the Ta- and Mayon showed signs of total of forty-six (46) minor vision camera, was observed. the reported ground rupture, tion of radio telemetered gaytay seismic station. This unrest in 2003 prompting ash ejections occurred from 7 On 09 October, sulfur dioxide conducted intensity survey, seismic monitoring system in will house all equipment and PHIVOLCS to raise their Alert March to 23 July 2003. These emission rates rose to 2,386 disseminated correct informa- 8 active volcanoes. In addi- software required to record Level status. Both volcanoes explosions were characterized tonnes per day (t/d) from the tion regarding the event and tion to the regularly monitored and process earthquake data produced ash explosions al- by steam emission with minor previous measurement on 01 installed additional seismo- 6 active volcanoes (Pinatubo, during such emergency. though no damage was in- amounts of ash that rose from October of 1,616 t/d. Because graphs to monitor the after- Taal, Mayon, Bulusan, flicted on the surrounding set- 100 to 1,500 meters above of these observations, shocks of the M 6.2 earth- Kanlaon and Hibok-Hibok), PHIVOLCS implemented tlements. A major earthquake the active crater. The Alert PHIVOLCS raised the vol- quake. Some school build- new seismic stations were in- 12 internally-funded and 9 ex- with magnitude 6.2 occurred Level status remained until cano’s status to Alert Level 2 ings, roads, bridges and river stalled in Mt. Parker in South ternally-funded and collabora- at Masbate and caused dam- the end of the year as vol- on 11 October 2003. This flood control structures sus- Cotabato and Mt. Matutum in tive research projects. In its age to structures in the prov- canic earthquakes conti-nued alert status, which indicates tained damages estimated to Saranggani. information dissemination ince. to occasionally occur which that the activity is of magmatic be about nine million pesos. A campaign, PHIVOLCS ac- still signify the possibility of origin that could eventually comprehensive QRT Report For earthquake monitor- tively organized 6 seminar- Kanlaon Volcano in sudden steam and ash explo- lead to an eruption, was of Investigation with recom- ing, the JICA Phase II in- workshops and trainings for Negros Island exhibited epi- sions. hoisted throughout the re- mendations to the local gov- volves the establishment of teachers, local government sodes of unrest throughout mainder of the year. ernment of Masbate was remote seismic stations and barangay officials in the year. The initial activity The 2003 activity of Mayon submitted by PHIVOLCS to whose data will be transmitted Metro Manila, Infanta, Batan- started on 20-22 January began on 30 January when a A relatively strong earth- the Province of Masbate after to the Data Receiving Center gas City, Lingayen and Ba- 2003 with increase in the brief episode of volcanic quake, with magnitude of 6.2, the 10-day investigation. at the Main Office in very near colod City. number of volcanic earth- tremor occurred. This event struck the southern part of real-time using satellite com- quakes. This activity was was followed by a small Masbate Island on February For the year, the Philip- munication. This type of short-lived that by 23 January, steam ejection in the after- 15, 2003. The epicenter of the pines’ 34-station network re- setup is the most efficient the earthquake count dropped noon of 31 January. No earthquake was about 28 km corded a total of 8,915 earth- method to conduct seismic to zero level. However, on 7 marked increase in the vol- southeast of Masbate City. It quakes, for an average of 24 monitoring since it will allow March, Kanlaon began exhib- cano’s activity was observed was felt at Intensity VII in the earthquakes recorded per PHIVOLCS to implement its iting small phreatic explosions until an explosion again oc- Masbate towns of Dima- day. The parameters (epicen- mandate of issuing earth- characterized by emission of curred from the crater on 17 salang, Palanas and Uson, In- ter, magnitude and depth) of quake information at a much steam with minor ash content. March 2003. The explosion tensity VI in Batuan and 1,001 detected earthquakes faster time thereby enabling This was again followed by produced an ash and steam Cataingan, Masbate, Intensity were determined. the Institute to serve the pub- another explosion that pro- column that rose to about one V in Masbate City, Irosin in lic better. At the same time, it duced a grayish steam col- kilometer above the summit. Sorsogon and Legaspi City, While Mayon and Kanlaon allows PHIVOLCS to upgrade umn on 17 March, which sug- Alert Level 1 was raised on Intensity IV in Palo, Leyte, were spewing ash, and a its instrumentation setup to gested that Kanlaon has en- the same day to remind the Naga City and Roxas City, In- magnitude 6.2 earthquake levels at par with more devel- tered a low-level episode of public of ongoing activity and tensity III in Cebu, Intensity II with minimal but significant oped countries minus the ex- unrest. Because of this, the to reiterate the restriction of in Anini-y, Antique and Inten- damage occurred in Masbate, pensive manpower and oper- Alert Level was raised from 0 entry into the 6-km Permanent sity I in Lezo, Aklan. A Quick PHIVOLCS was also busy in- ating and maintenance costs to 1 and the public was re- Danger Zone around the vol- Response Team (QRT) was stalling new observation sta- required for this kind of en- minded not to venture inside cano. Three more episodes of deployed to Masbate Island tions under the project “Im- deavor. In addition, broad- the 4-km Permanent Danger ash explosions occurred on on 18 February to evaluate provement of Earthquake and band seismographs were also Zone. The mild unrest 05 April and 06 & 14 May. the extent of the earthquake- Volcano Monitoring Network established in several Table 1. Kanlaon Volcano’s Activities in 2003 Chronology of Events VV oollccaannoo MMoonnii ttoorriinngg HEIGHT ACTION DATE TIME OBSERVATIONS (m) TAKEN/REMARKS The year 2003 was a very busy and brief and small, the ash column rose only to Fig. 1. January 2001 ash explosion at Mayon Vol- 07 March 1250H – 1300H 500 - 1000 Mild ash ejection; drift: SW; Advisory issued on 08 fruitful year for PHIVOLCS. Timely volcano less than 100 m. above the crater rim. Only cano. A similar event oc- 2003 traces of ash at Cabagnaan March 2003 alerts were hoisted over Kanlaon in Negros trace ash deposits were observed along curred last 17 March 2003 17 March 0400H – 0600H 300 Ash ejection; drift: SE Advisory issued (0800H) and Mayon Volcano in Albay. Both volca- downwind areas NW & SW of the crater. 2003 Traces of ash at Cabagnaan Alert Level 1 raised (1400H) noes produced ash explosions although no 23 May 2003 1351H – 1405H 300 – 500 Dirty white steam damage was inflicted partly because of dili- On 7 October, faint crater glow seen 01 June 2003 0846H – 0858H 500 Dirty white steam drifting SE-NW gent monitoring and enhanced awareness to only with telescope or night vision camera 03 June 2003 1002H - 1015H 500 – 700 Dirty white steam drifting NW avoid the danger areas. While Mayon and was observed (Figure 2). The glow was per- 04 June 2003 0515H – 0600H 300 – 700 Dirty white steam drifting NW 07 June 2003 0519H – 0530H 500 – 1000 Ash ejection; drift SE Kanlaon were spewing ash, PHIVOLCS was sistent and appeared to be sourced from 08 June 2003 0601H – 0605H 500 – 1000 Ash ejection; drift: SE; Alert Level 1 reiterated also busy outfitting new radio-telemetered lava deposits inside the crater. Sulfur Diox- 0637H – 0645H traces of ash at Canlaon City seismic stations in 8 active volcanoes. In ide emission rates on 9 October rose to proper, Upper Mananawin, Masu- log, Linothangan, Alebabay & Lu- addition to the regularly monitored 6 active 2,386 tonnes per day (t/d) from the previous cap volcanoes, new seismic stations were em- measurement of 1,616 t/d of 1 October 09 June 2003 0604H – 0605H 500 – 1000 Dirty white steam drifting SE placed at Mt. Parker in South Cotabato and (Figure 3). As a result of these observations, 0637H – 0645H 0843H – 0854H Mt. Matutum in Saranggani as part of the PHIVOLCS raised the volcano’s status to 10 June 2003 0607H – 0612H 500 – 1000 Dirty white steam drifting SE improvement of earthquake and volcano Alert Level 2 on 11 October 2003. 0705H – 0710H monitoring system (Phase II) project as- 1421H – 1435 sisted by JICA. Electronic tiltmeter readings at both 11 June 2003 0551H – 0600H 1000 Dirty white steam drifting SSE Fig.