Reflection Survey

Todd Hansen

Diana Hooper

Michelle Heimgartner

Seismic reflection

Methods

• Bison Galileo 21• 2-24 channel cables spaced 2 m apart• Seismic source: 10-lb sledgehammer,

10 hits every 4 meters• Six 100 Hz geophones per group• Geophone groups overlapped to

diminish noise• Records were 0.5 s

Sources of potential error

• Noise:– Wind - rattles geophones (windy on both

days)– Soft sediment - attenuation of seismic

waves

• Bad geophone plants

• Not error - loss of precision by overlapping the geophone groups

Processing Methods

• Viewmat500

• Bandpass filter of 75-150 Hz with a 20% taper

• Trace-edit to erase noisy traces (multiply the amplitude of the trace by zero)

• Common Velocity Stack

• Common Midpoint Stack

Hazen reflection profile

Hazen cvstack profile

Hazen cmpstack profile

Fernley reflection profile

Fernley cvstack profile

Fernley cvstack profile

Fernley cmpstack profile

Thrust fault interpretation

Drape Fold Interpretation

Conclusions

• Fault???