Have you ever described a rock? It must be pretty often. What if the rock you must described located 50m beneath the earth surface? In that case, we should know about petrophysic.
Petrophysic derived from word petro = rocks and physic = science of physical activity. Petrophysic is Petrofisika is the branch of geology that uses physical and statistical methods to decrypt rocks. The rocks located beneath the earth surface, the need of petrophysic are crucial in this circumstance.
Undip SC of AAPG held a discussion about “Basic Petrophysic” on 6th of April 2013. The goal of this discussion is sharing knowledge about basic petrophysic in Geological Engineering of Diponegoro University. Undip SC of AAPG, cooperating with Geology Research Club (GRC), presents Rizki Ramadhan and Mega Sari as a speaker in this discussion.
Rizki Ramadhan and Mega Sari, Geological Engineering student grader 2008, was a delegate for a seminar in ITB. Yes, the seminar was about basic petrophysic. So that they can share the knowledge they have in this discussion.
The method used in petrophysic is similar to the method used in geophysic, applying seismic wave. Seismic method has a wave source that emits the seismic wave under the earth surface. The wave will travel beneath the earth sureface until it reaches the maximum wave length. Then, it will be reflected or refracted when it reach the boundary of a lithology. The refraction or reflection is a cause of density different. The reflected wave will reach back to the earth surface and then received by geophone. The wave that travels back contain information which will be used in interpretation and resulting a seismic profile.
Generally, they have a similar method. But in petophysic, the different is located in the parameter. The parameters used in petrophysic are density, resistivity, neutron, gamma ray, and spontaneous potential. The parameters have different result when the wave gets a contact with different lithology. For example, a coal will show a low density and high resistivity reading.
The discussion took place in Seminar Room with more than 40 participants.