Does the SAN log traffic usage data and export them as logs? I dont think so - I believe you should explore NetFlow monitoring at access or core layer. LEM does support NetFlow sources and a few NetFlow reports too. Of course, your switch will need to support NetFlow or sFlow export for this to work.
If your requirement is bandwidth analysis alone, look at NetFlow Traffic Analyzer.
If your switch does not support NetFlow or if you want more granular information there is another option. We develop a product called LANGuardian which integrates with Orion. It uses network packets (SPAN\mirror port or TAP) as a data source. As well as getting traffic volumes and alerts you can drill down and see what files\directories are moving around your network and what user is associated with the activity. We have an online demo available (no registration required) at the link below which shows a sample of what can be done.
You can also check out the integration in the video below. This video is based on SolarWinds NPM but you can do similar things with LEM as it's all based on the Orion platform.
Hope this helps,