Gravity anomalies only occur when which of the following Earth contrasts are impacted?

Gravity anomalies only occur when which of the following Earth contrasts are impacted?

• A. Density
• B. Temperature
• C. Humidity
• D. Pressure

Answer: (A)

Gravity anomalies arise from differences in how much mass is packed into a given volume. Since gravity is the pull from all surrounding mass, a region with higher density than its surroundings adds more mass and strengthens the local gravitational pull, creating a positive anomaly; a region with lower density reduces the pull, giving a negative anomaly. Temperature, humidity, and atmospheric pressure can affect density indirectly, but the anomalies we measure for subsurface structure come from density contrasts in rocks and minerals. So the factor that actually drives gravity anomalies is density contrast.

Gravity anomalies arise from differences in how much mass is packed into a given volume. Since gravity is the pull from all surrounding mass, a region with higher density than its surroundings adds more mass and strengthens the local gravitational pull, creating a positive anomaly; a region with lower density reduces the pull, giving a negative anomaly. Temperature, humidity, and atmospheric pressure can affect density indirectly, but the anomalies we measure for subsurface structure come from density contrasts in rocks and minerals. So the factor that actually drives gravity anomalies is density contrast.