[Pooya/Ali Commentary 69:4] See commentary of Araf: 65 to 79 and Hud: 50 to 68 for the people of Ad and Thamud. Qariah means "striking calamity", another description of the day of judgement which the people of Ad and Thamud belied. This word Qariah is also the title of surah 101. The people of Ad were destroyed by a terrible blast of wind; and the people of Thamud were destroyed by an earthquake accompanying a terrible thunderstorm. The calamities were thorough.