GADJAH MADA GEOPHYSICS 

INSTRUMENTATION GROUP

RESEARCH OBJECTIVES

We are interested in Geophysical Instrumentation & Geophysical equipments hardware. 

PEOPLE

This Group led by Mr. Drs. Suparwoto. The members are students who interested to hardware & geophysical instrumentation.

RESEARCH LINKAGES

	Coperation with PT, Handhaya, Bandung in developing of volcanic parameter measurement by means of a telemetry system for the Kelut Volcano in Eastern Java.
	Cooperation in Geophysical Instrumentation with Geotechnological Research and Development Center (Puslitbang Geoteknologi LIPI).
	Cooperation with GEOFON Project, Potsdam Germany on Seismology. Installation, data acquisitions and processing for global digital of Seismographic group.
	Research in Geophysical Instrumentation (Puslitbang Geotecnology LIPI)

RESEARCH

ABSTRACT

CALIBRATION AND TESTED HORISONTAL LOOP

ELECTROMAGNETIC DEVICE

 By:

M. Zainal Arifin

Horizontal loop electromagnetic device consists of two main parts  transmitter and receiver. Electromagnetic fields will  appear on the surrounding of the loop receiver if any current flows on it. The Electromagnetic field measured directly from transmitter by the receiver is called primary field (H^p). If the field encounters a conductive body in the subsurface, there will be eddy current in it. Eddy current in the body led another field that receives by receiver as secondary field. The ratio of primary field and secondary field can indicate  the appearances of conductive body.

Calibration is needed by bring it out to the area that has zero conductivity or calibrating by separated it away from any conductive substances.   Because it is hard to find the non-conductive area (conductivity = 0) and extremely difficult to separate the loop away from any conductive substances, the calibration was undergone in relative way. Calibration was undergone in low conductivity area. For area that has not influenced by conducting substance H^s/ H^p can be calculated theoretically. Based on theoretically calculation the device reading can be adjusted.

This device gave responses that match with cylindrical model responses for test with Pertamina pipe as target in Pedes, Bantul. This device can map mineral deposit in Wonogiri, Central Java that result is match with result by another geophysical method.