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Gravity Lab: The Cross-Section Challenge

Mission: Process the gravity data for 4 stations to reveal the hidden geological structure.

Phase 1: Latitude Correction ($g_\phi$)

$$ g_\phi = 9.780318 \left( 1 + 0.0052789 \sin^2 \phi + 0.0000235 \sin^4 \phi \right) \text{ m/s}^2 $$

⚠️ Note: Multiply result by 100,000 to get mGal.

Station Latitude ($\phi$) Calculated $g_\phi$ (mGal) Status
145.00°
245.15°
345.30°
445.45°

Phase 2: Elevation Corrections (FAC & BC)

$$ FAC = 0.3086 \times h \text{ (mGal)} $$ $$ BC = 0.0419 \times 2.67 \times h \text{ (mGal)} $$
Station Elev ($h$) FAC (+) BC (-) Status
1100 m
2150 m
3400 m
4800 m

Phase 3: Geological Interpretation

$$ BA = g_{obs} - g_\phi + FAC - BC $$
Station $g_{obs}$ (Raw) Final BA (mGal) Interpretation
1 980,599.7 Background
2 980,573.2
3 980,567.2 Transition
4 980,601.7