Consider the characteristics of seismic waves generated during an earthquake: Statement I: Primary waves are longitudinal waves that can travel through both solid and liquid rock layers. Statement II: Secondary waves are transverse waves that can propagate exclusively through solid media. Which of the following is correct?

💡 Solution & Explanation

Primary waves are compressional body waves capable of propagating through solid rocks as well as liquid layers because their particle motion is parallel to wave propagation, whereas secondary waves are shear waves that move perpendicular to the direction of travel and are completely absorbed by fluids due to zero shear resistance. Alternative interpretations suggesting secondary waves pass through liquids are physically invalid in geophysics. Seismograph stations utilize the time interval between the arrival of primary and secondary waves to determine the epicenter of seismic events.