Which of the following statements with reference to shadow zones in an event of an earthquake is/are correct ? 1. Zone between 105° and 145° from epicentre was identified as the shadow zone for both P-waves and S-waves 2. The shadow zone of P-waves is much larger than that of the S-waves Select the answer using the code given below :

Seismic shadow zones are regions where specific body waves are not detected by seismographs. Statement 1 is correct because the zone between 105° and 145° from the epicenter is identified as a shadow zone for both P-waves and S-waves [3]. While P-waves are refracted by the liquid outer core, creating a band-like shadow zone in this specific range, S-waves are completely blocked by the liquid outer core [2]. Statement 2 is incorrect because the S-wave shadow zone is significantly larger than the P-wave shadow zone [1]. The S-wave shadow zone extends to the entire region beyond 105° from the epicenter, covering over 40% of the Earth's surface, whereas the P-wave shadow zone is limited to a specific band between 105° and 145° [1]. Beyond 145°, P-waves reappear, but S-waves do not [3].

Sources

1. [1] FUNDAMENTALS OF PHYSICAL GEOGRAPHY, Geography Class XI (NCERT 2025 ed.) > Chapter 2: The Origin and Evolution of the Earth > Emergence of Shadow Zone > p. 20
2. [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 5: Earths Magnetic Field (Geomagnetic Field) > Shadow Zone For Both P Wave and S Wave > p. 64
3. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 4: Earths Interior > P Wave Shadow Zone > p. 63