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Velocity of Rocks

Measure sides of your rock sample using the caliper (Zero the tool). Record three measurements per side and calculate the average distance in mm.

Set-Up Equipment (V-Meter MK IV)

1. Equipment: V-Meter MK IV yellow box, 2 Transducers (source and receiver), cables, and charger

1. Safety remark: Don’t twist the cables

1. Connect the transducer (source) cable

1. Connect the receiver cable

1. Connect charger

1. 2 Transducers (Source and receiver)

1. Apply CIP Lube to the sample/rock surfaces (a little goes a long way)
2. Turn on the V-Meter

1. Set acquisition parameters (Setup Menu)

1. After turning on the V-Meter, press the “ESC” button to go to Main Menu

1. Amplifier gain (50)

1. Picture rate (2 mHz)

1. Pulser voltage (Low)

1. Calibrate transducers  (Setup Menu > Calibrate Transducers)

1. Transducers should be aligned

1. Keep a little pressure

1. The V-Meter will automatically change the gain in the calibration process

1. Wait until it says “Calibration is done”

How often do we calibrate? We should calibrate every time we change the voltage, number of pulses, and gain.

1. Set P-distance in the V-Meter
2. Convert the rock sample distance into meters

1. Measure rock velocity (Test Menu)

1. Measure velocity within the test menu

1. Apply a little pressure to keep the transducers pressed against the rock sample (use more CIP lube if needed)

1. Analyze results
2. Does the obtained velocity value agrees with regular/published velocities according to the rock type?

Exercise:

1. Measure the velocity of:

1. Granite sample

1. One rock from the little square rock kit inside the V-Meter box