Ulwelo lwesulphur emnyama yidayi edla ngokusetyenziswa ukudaya amalaphu, ngakumbi amalaphu ekotoni. Ulwelo lwesulfure emnyama inomthunzi obomvu kunye noluhlaza okwesibhakabhaka, onokuhlangabezana neemfuno ezahlukeneyo zabathengi.
Ukudaya kwedenim kunye nokudaya kwelaphu, ixabiso liphantsi kakhulu kunomnye umbala omnyama wedayi.