60934
He rappelled into the Inner Crater of Mount Erebus in 1978 , but had to be pulled out when an eruption showered him and colleagues on the crater rim with volcanic bomb s ; one of the leading volcanic gas geochemist s of the period .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None