GeophysicsGeophysicsBy

RUSTAN EFENDI2011-2014

Geology + Physics=Geology + Physics=

Geophysics

The Even SemesterThe Even Semester

Seismic MethodSeismic Method

Syllabus of the Seismic Method:Syllabus of the Seismic Method:• IntroductionIntroduction

• Theoretical backgroundTheoretical background

• Elastic parametersElastic parameters

• Seismic WavesSeismic Waves

• Propagation of the seismic wavesPropagation of the seismic waves

• Seismic velocitySeismic velocity

• Geometry of reflected wave pathGeometry of reflected wave path

• Geometry of refracted wave pathGeometry of refracted wave path

• InstrumentsInstruments

• Data CorrectionsData Corrections

• Data ProcessingData Processing

• InterpretationInterpretation

ReferencesReferences::

1.1. Applied GeophysicsApplied Geophysics,, 19961996, , Telford, W.,M.Telford, W.,M.

2.2. An introduction to applied and environmental An introduction to applied and environmental geophysics,geophysics, 19971997, , Reynolds, J. M.Reynolds, J. M.

3.3. Introduction to geophysical prospectingIntroduction to geophysical prospecting, , 19881988, , Durbin, M. B.Durbin, M. B.

4.4. Applied and environmental geophysicsApplied and environmental geophysics, , 19991999, , Sharma,V.,P.Sharma,V.,P.

5. www.Geophysics.Com6. www.Geophysics.netet

The basic techniques of the seismicThe basic techniques of the seismic method method

1- Seismic Refraction1- Seismic Refraction

• Rock competence for engineering applications Rock competence for engineering applications • Depth to Bedrock Depth to Bedrock • Groundwater exploration Groundwater exploration • Correction of lateral, near-surface, variations in seismic reflection Correction of lateral, near-surface, variations in seismic reflection

surveys surveys • Crustal structure and tectonicsCrustal structure and tectonics

2- Seismic Reflection2- Seismic Reflection

• Detection of subsurface cavities Detection of subsurface cavities • Shallow stratigraphy Shallow stratigraphy • Site surveys for offshore installations Site surveys for offshore installations • Hydrocarbon exploration Hydrocarbon exploration • Crustal structure and tectonicsCrustal structure and tectonics

ApplicationsApplicationsSeismic method divides into two techniques:

• Seismic RefractionSeismic Refraction: the signal returns to the : the signal returns to the surface by refraction at subsurface interfaces, surface by refraction at subsurface interfaces, and is recorded at distances much greater than and is recorded at distances much greater than depth of investigationdepth of investigation

• Seismic ReflectionSeismic Reflection: the seismic signal is : the seismic signal is reflected back to the surface at layer interfaces, reflected back to the surface at layer interfaces, and is recorded at distances less than depth of and is recorded at distances less than depth of investigationinvestigation

Refraction Vs. ReflectionRefraction Vs. Reflection