CREATE TABLE table_name_15 (year INTEGER, death_toll VARCHAR(255), cause VARCHAR(255), colliery VARCHAR(255))
Count the lowest Year which has gas explosion, Colliery of tylorstown colliery, and a Death toll larger than 57?
    
SQL: SELECT MIN(year) FROM table_name_15 WHERE cause = "gas explosion" AND colliery = "tylorstown colliery" AND death_toll > 57