Gravity Survey Lab: Multi-Station Loop

Correcting for linear instrument drift over a full morning survey.

1. Survey Parameters

You performed a gravity survey lasting 5 hours. The gravimeter reading at the Base Station decreased by the end of the survey due to spring relaxation.

$$ \text{Drift Correction} = -(\text{Drift Rate} \times \Delta t) $$
$$ g_{corrected} = g_{obs} + \text{Drift Correction} $$

(Hint: If the drift is negative, the correction must be positive to compensate!)

2. Data Reduction Table

Calculate the Time Elapsed ($\Delta t$), the specific Drift Amount, and the final Corrected Gravity for all 5 stations.

Step 1: Calculate Global Drift Rate (mGal/min):

Time	Station	Raw ($g_{obs}$)	$\Delta t$ (min)	Drift (mGal)	Corrected $g$ (mGal)
08:00	BASE (Start)	980.00	0	0.00	980.00
08:30	Station 1	982.00
09:15	Station 2	985.50
10:00	Station 3	979.20
11:00	Station 4	988.10
12:00	Station 5	981.40
13:00	BASE (End)	978.50	300	-1.50	980.00