Mechanism Evaluation, Risk Assessment, Prediction Improvement

time frame of experiment: 1997 - 2001
publications: see publication list, MT related publications
related web ressources: MERAPI, LOTEM, NASA, VSI, Smithsonian Institute

The aim of the magnetotelluric part of the MERAPI project is to test the magnetotelluric method for its ability
 

• to obtain information about the electrical conductivity structure of the volcano
• to monitor volcanic activity by recording electric and magnetic field variations

We carried out three field campaigns over the period 1997 - 1999. The project can be subdivided into three subjects:


1. Regional studies of the electrical conductivity structure of Central Java

To examine the electric environment of Merapi volcano, we measured magnetotellurics at nine sites on a profile across Central Java during six weeks in 1997. The long measuring period was necessary to obtain reliable results for long period signals. Long periods represent a large subsurface volume.


2. Local studies of the conductivity structure at Merapi volcano

We carried out magnetotelluric measurements at 45 sites during three field campaigns for a period range 0.0005 - 1000s.
Results have been presented at:
 

• Electromagnetic Induction Workshop 2000 in Cabo Frio (Brazil) [more]
• IAVCEI meeting in Bali (Indonesia) [more]
• EGS meeting in The Hague, 1998 [more]

3. Monitoring of electric and magnetic signals during an active phase of Merapi volcano in July 1998
In June/July 1998 magnetotelluric recordings have been carried out during an active phase of Merapi volcano. A description of the activities is given by the Smithsonian Institution. First results of these measurements have been presented at the IUGG meeting in Birmingham 1998:
 

• Coseismic electromagnetic variations measured during an eruptive phase of Merapi volcano (Central Java) [more]