(Q022) A negative magnetic anomaly a. occurs when the Earth's magnetic field measured in ancient rocks is the same as it is today. b. is created when weak magnetic forces in basalt grains add to the force produced by the Earth's dipole. c. describes the sawtooth pattern of magnetic signal strength measured along the Atlantic Ocean seafloor. d. is indicated when a magnetometer measures intervals of magnetism that are weaker than expecte

d. Is indicated when a magnetometer measures intervals of magnetism that are weaker than expected

Explanation:

Magnetic field intensity is measured with a magnetometer on the surface of the Earth. Areas in which the magnetic field strength is lower or more than average are known as areas with magnetic anomalies, which may be due to  the presence of rocks that have a different magnetic characteristics

Where the magnetic anomaly is negative, it is indicative of a magnetic field strength reading that is lower than average magnetic field which is generally obtainable

Therefore, the correct option is indicated when a magnetometer measures intervals of magnetism that are weaker than expected