The Geological Agency of the Energy and Natural Resources Ministry has officially declared nine unique geological rocks located in the Yogyakarta Special Region to be geo-heritage sites.
The nine sites comprise Eosen limestone in Gamping (Sleman regency), pillow lava in Berbah (Sleman), pre-historic volcanic sediment in Candi Ijo, Prambanan (Sleman), sand dunes in Parangtritis Beach (Bantul regency), Kiskendo cave and former manganese mining site in Kleripan (Kulonprogo regency), the prehistoric volcano in Nglanggeran (Gunungkidul regency), Wediombo-Siung beaches (Gunungkidul) and Bioturbasi site in Kalingalang (Gunungkidul).
“Yogyakarta province is the only place in Indonesia that has geo-heritage sites,” the Energy and Mineral Resources Ministry’s geology agency head, Surono, told The Jakarta Post over the weekend.
Surono handed over the agency’s document regarding the geo-heritage sites to Governor Hamengkubuwono X at the Kepatihan gubernatorial office on Friday.
Surono expressed hope that regional administrations would be able to protect the geo-heritage areas and develop them into tourism and research regions. He said the central government could help provide the scientific studies for the further development of the sites.
“Declaring these sites to be geo-heritage sites will lead to environmental preservation efforts, and local people can develop tourism and the creative economy,” he said.
He said the process to declare the nine places to be geo-heritage sites was serious and lengthy, involving field observations, scientific studies and focus group discussions involving the community.
“We only agreed on nine of the proposed 11 sites,” Surono said.
The decision received a warm welcome from researcher Destha Titi Raharja of Gadjah Mada University’s Center for Tourism Studies, saying that it added to the variety of educational tourist destinations.
“The administrations from the subdistrict up to the regency levels have to make regulations to protect and develop the sites,” Destha said.
He added that some geo-heritage sites had not yet been optimized as educational tourist destinations.
Among the sites already developed as tourist destinations include the Nglanggeran volcano site, which offers beautiful scenery.
Of the nine sites, the one considered the most unique is the pillow lava in Berbah. It is a big, rough black rock located on the bank of the narrow Dengkeng River.
According to Surono, the lava initially was located on the seabed and rose to the surface over a period of tens of millions of years.
Unfortunately, not many people know about this particular site. Only students majoring in geology or soon-to-be-married couples visit, for research purposes and pre-wedding photos, respectively.
Geologist Prasetyadi of the Yogyakarta Veteran National Development University (UPN) said that the pillow lava marked the old andesite formation era in the southern parts of Java between 36 and 16 million years ago.
“The lava that was coming out from the belly of the earth froze when it touched the sea water,” Prasetyadi said.
The prehistoric volcanic sediment at the Candi Ijo temple area was, according to Prasetyadi, a Semilir formation, petrified volcanic ash resulting from a super eruption of a prehistoric volcano name Mount Semilir.
Some of the prehistoric volcanic sediments have been damaged by mining activities by local people. The same prehistoric volcanic sediments were also found at the site of the pillow lava, according to Prasetyadi.