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fficials have called on residents living near Mount Tangkuban Parahu in West Java to remain calm and not willingly believe rumors surrounding the mountain’s recently increased volcanic activity.

The Volcanology and Geological Disaster Mitigation Center (PVMBG) head Surono said the eruption of Mt. Tangkuban Parahu, which is situated on the border of the West Bandung and Subang regencies, was not magmatic in nature like the Mt. Merapi eruption in Yogyakarta.

“The Mt. Tangkuban Parahu eruption is phreatic in nature. It contains a lot of steam and could be followed by volcanic material, such as ash and dust,” Suraono said in Bandung on Friday.

Surono’s statement was contrary to widely circulated information through a message broadcast saying: “For residents of Bandung and surrounding areas, Mt. Tangkuban Parahu’s status has been raised to alert 1 level and it has discharged molten lava at a height of 3 meters. The resort area is officially closed. In the event of a quake, please get out the house.”

According to Surono, Mt. Tangkuban Parahu has an open crater that is quite large. Besides that, energy from within the volcano is vented simultaneously through phreatic eruptions, while Mt. Merapi is cone-shaped, making it possible for magma to accumulate within it.

The seismic activity of Mt. Tangkuban Parahu is currently decreasing. Surono said on Friday that from midday, two shallow volcanic quakes and one deep volcanic quake were recorded.

He compared the quake frequency with data collected on March 6 when the number of deep quakes reached five times a day. “Normally, the number of deep quakes in Mt. Tangkuban Parahu is between four and five times a month,” he said.

Besides paying attention to seismic data, Surono also noticed the accumulation of gas in the Ratu Crater, from which the phreatic eruptions occurred in the past several days. Based on analysis conducted by his team, sulfur dioxide (SO2) contents there reached 4.4 tons daily. The amount is still at the normal level of four tons daily.

“There is no data on CO2 [carbon dioxide] and carbon monoxide [CO]. When the magma level rises, usually CO2 and CO contents also rise,” said Surono.

He compared the accumulation of CO2 monitored in Mt. Merapi prior to the eruption in 2012 to 180 kilotons daily.

It is recommended that no human activity take place in the 1.5-kilometer radius from Ratu Crater, a tourist focal point at the location.

Besides the quakes, the volcano also discharged dust, which has been carried by wind at a radius of 5 kilometers from the crater.

The light dust can be noticed covering tea leaves around the mountain area.

“The dust is very light and need not be worried about,” Surono explained.

West Bandung Disaster and Mitigation Agency (BPBD) head Maman Sulaiman said residents who wished to get information on the latest development of the volcano could come to the observation post on Mt. Tangkuban Parahu.

“The post is manned by volcanic observers and us, so you can get exact information there,” said Maman.

Residents who wish to get the latest information on volcanic activities can contact the PVMBG at (022) 7272606.