The tool that you can use to analyze the verboseGC is GCMV & PMAT. Take a look at the following links for details.
http://www.ibm.com/developerworks/websphere/library/techarticles/1003_munse/1003_munse.html
https://www.ibm.com/developerworks/java/jdk/tools/gcmv/
https://www.ibm.com/developerworks/community/groups/service/html/communityview?communityUuid=22d56091-3a7b-4497-b36e-634b51838e11
http://www-01.ibm.com/support/docview.wss?uid=swg27007240