Myanmar students, Khin Nyein Nyein Tun, succeeded to earn doctoral degree in Geology Engineering at Faculty of Engineering Universitas Gadjah Mada after defending her dissertation in an open examination at Geology Engineering Department on Monday (31/7). Her promoter was Prof. Ir. Dwikorita Karnawati, M.Sc., Ph.D. whilst the co-promoters were Dr. Ir. Ahmad Rifa’i, M.T. and Prof. Hiroyasu Ohtsu.
In her dissertation entitled Assessment of Stability of Hydrothermal Volcanic Rock Slope in Gedongsongo, Ungaran, Central Java, she said the high intensity of rock alteration forms a thick clay that significantly reduces the shear strength, particularly during the rainy season, and causes slope instability that keeps increasing, thus risking a landslide. “Most of the landslides in the slope area occur at a high hydrothermal alteration intensity on the andesite rock and it cohesively changes into clay,” said Khin.
She further said volcanic clay that is formed with high hydrothermal intensity induces argillic alteration as the factor that triggers the occurrence of volcanic rock slope failure. Gedongsongo area is located in the southern part of Ungaran Volcano where there are geothermal resources, including fumarole, steam soil, and hydrothermal alteration rock which has an acid characteristic, thus causing the instability of volcanic rock slope that can be dangerous for the people in the volcanic areas. “Hence, assessment of the stability of hydrothermal volcanic rock slope becomes very important for the geothermal resource area,” she added.