Understanding the trigger for the LUSI mud volcano eruption from ground deformation signatures

Abstract

The LUSI mud volcano in the sub-district of Porong, Sidoarjo, East Java, Indonesia started to erupt on 29 May 2006. An almost continuous eruption of a mixture of mud, water and gas has occurred around this area since this date. The eruption triggered vertical and horizontal ground deformation. From June 2006 to December 2010, 14 global positioning system campaigns were conducted to observe the ground deformation using c. 50 stations sparsely located up to 10 km from the eruption centre. Field observations of cracks, terrestrial laser scanning and geo-electrical measurements have also been used to infer the ground deformation signature around the LUSI mud volcano. More than 150 pairs of interferograms generated from 66 ALOS PALSAR images from June 2006 to December 2009 have also been used to study the ground deformation caused by the LUSI mud volcano. The LUSI mud eruption began only 200 m from where the Lapindo Inc. oil company was drilling for oil and gas. The drilling may have pierced a deeper high-pressure zone, causing an underground blow-out of the drillhole into a hydrofracture. Alternatively, the magnitude 6.3 Yogyakarta earthquake, which was located c. 275 km from the eruption site and occurred two days before the LUSI eruption, may have shaken the area sufficiently to cause the eruption by reactivating a fault in the region and liquefying the mud. These two hypotheses for triggering the mud volcano have been argued vehemently and still remain controversial. The ground deformation signatures provide important clues to understanding the trigger for the eruption and to solve this controversy. Co-seismic fault reactivation has its own typical ground deformation signature. This study used global positioning system and InSAR techniques, as well as field observations of cracks, terrestrial laser scanning and geo-electrical measurements, to determine the signature of ground deformation around the LUSI mud volcano and to explain the triggering mechanism.

Aplikasi Penginderaan Jauh Dan Sistem Informasi Geografis Untuk Pemodelan Jalur Alternatif Pembuangan Lumpur Sidoarjo

“…Peristiwa tersebut berdampak pada lingkungan fisik dan sosial. Permukiman, kawasan industri, dan infrastruktur terendam lumpur, bahkan dalam radius tertentu ditemukan retakan pada dinding bangunan (Andreas et al, 2017) sehingga diputuskan dalam Sidang Kabinet Paripurna pun digelar pada 27 September 2006 bahwa lumpur dialirkan menggunakan spillway ke laut melalui Sungai Porong. Namun pencemaran lingkungan terjadi, baik pencemaran air, tanah maupun udara (Putri & Yudhastuti, 2013).…”

A Quick Assessment Method for the Mud Eruption Hazard Risks of the Lusi Surrounding Area with a Special Reference to Ground Deformation Behavior

“…A different hazard risk index could be developed to other different hazard types [9,10,11]. In the case of ground deformation, the measurement of the ground movement is commonly used to gain detailed movements using geodetic methods [7,8,12], or geophysical methods [13,14,15,16]. Therefore, a risk index is just to provide a general indication how the area being investigated will have fatalities when any given disaster occurs.…”