Biri Rock Formation named national geological monument

TACLOBAN CITY — The Biri Rock Formation in Northern Samar has officially been designated a National Geological Monument (NGM), bringing the total number of recognized sites in the country to seven.

Governor Harris Ongchuan, along with Representative Edwin Ongchuan and Biri Mayor Antonio delos Reyes Jr., received the official declaration documents from the National Committee on Geological Sciences (NCGS) on 18 November.

The Biri Rocks join an elite list of six other sites, including the Taal Volcano in Batangas, Chocolate Hills in Bohol, Montalban Gorge in Rizal, the Ilocos Norte Sand Dunes, the Hundred Islands in Pangasinan, and the St. Paul Limestone Formation in Puerto Princesa.

Dr. Kevin Garas, supervising geologist of the Mines and Geosciences Bureau, stated the designation was based on the formation’s exceptional geological characteristics, scientific importance, uniqueness, and natural beauty.

A thorough study by experts led by Dr. Allan Gil Fernando of the University of the Philippines-National Institute of Geological Sciences (UP-NIGS) detailed the site’s unique features.

The study highlighted the occurrence of phonolite — a volcanic rock — and analcime clasts within the conglomerate sandstone strata, which helps unravel the magmatic history of alkaline rocks in Northern Samar.

The rocks consist of tilted marine sedimentary sequences of conglomerates, sandstones, siltstones, and shales formed about 15-20 million years ago.

Tectonic and wave processes sculpted these sequences into seven picturesque islets that comprise the Biri Rocks — Magasang, Magsapad, Macadlaw, Puhunan, Bel-at, Caranas, and Pinanahawan.

In related news, the provincial government, under Ongchuan, committed to pursuing a bid for UNESCO Global Geopark status, continuing the initiative started during Representative Ongchuan’s term as governor. This effort seeks to promote sustainable, heritage-based, and inclusive development in the province.