US Patent 11960443 Block data storage system in an event historian

An event historian system receives event data from a client system via a network connection and stores the event data in a block data storage system. An event data block in which to store the received event data is selected based on the time range of the occurrence of the received event data. The received event data is stored in a snapshot within the event data block. Event property data is extracted from the received event data and used to build a plurality of event property index files.