Three major programs of the Mines and Geosciences Bureau-IX thru the Geosciences Division, commenced this February in line with the national targets of DENR-MGB. These field programs are Geologic Quadrangle Mapping, Updating of 1:10,000 scale Geohazard Map and Vulnerability and Risk Assessment (VRA), and Coastal Geohazard Assessment undertaken in the various provinces of Zamboanga Peninsula.
Geologic Quadrangle Mapping
The geologic mapping in Bagolibud Point Quadrangle mostly covers the Municipality of Tungawan, Zamboanga Sibugay. Field activities of this program include examination of rock exposures along with accessible tracks and in coastal areas, physical and megascopic description of outcrops and rock samples, structural feature measurements of prevalent deformation and sedimentary structures, and rock sampling of representative lithology and favorable units that contain fossils and minerals.
Photo 1: An exposure along the coastal section of Brgy. Linguisan, Municipality of Tungawan, Zamboanga Sibugay is being examined in detail by the mapping team. This is a melange body composed of turbidite sequence, chert and talc-chlorite schist in contact with the ultramafic block.
Coastal Vulnerability and Assessment Mapping
As part of the National Geohazard Assessment and Mapping Program, a team is undertaking a coastal geohazard assessment along the coast of the Municipalities of Salug and Leon Postigo, Zamboanga del Norte. This program aims to identify the physical vulnerabilities to the changing climate that can cause accelerated sea-level rise, coastal erosion, subsidence and coastal floodings that could potentially bring significant impacts on livelihood, infrastructure, environment and built-up areas along the coastline.
Photo 2: Assessing the physical damage along the coast in Purok 7, Brgy. Mucas, Municipality of Salug. Advancing wave height devastated sections of built-up areas made from concrete and light materials. As reported by the locals, the incident occurred in January 2022.
Geohazard Map Updating and Vulnerability and Risk Assessment (VRA)
As a flagship program under the National Geohazard Assessment and Mapping Program, the MGB-IX team is starting off its program in the Municipality of Tigbao, Zamboanga del Sur. The program is set to update the present 1:10,000 scale geohazard map of the municipality and assess the vulnerabilities of elements at risk (population, built-up areas and infrastructure) from the different susceptibilities to hydrometeorological hazards, flooding and landslides. Output of the program is crucial in the formulation of various municipal plans such as land-use, disaster preparedness and other programs of the target municipality.
Photo 3: Part of the assessment is conducting anecdotal interviews in the barangays of the municipality. Above photo shows a barangay official of Brgy. Begong, Municipality of Tigbao being interviewed regarding the susceptibility of landslides and possible areas occurring in flood prone zones. Threat advisory is also issued with regards to the hazards identified in the area and its corresponding recommendations.
Other equally important programs of the division such as the intensive Information, Education and Communication (IEC) Campaign on the Geohazard and VRA Maps and Groundwater Resource Assessment, are also set to start within the quarter .