What do the white circle and black arrow on the airport chart mean? (VOR identifier and frequency written) There are 2 on the chart. Also, is there a document where I can find the meanings of the symbols on the airport chart? The document is from Turkey AIP.
I believe that the circle and black arrow (with the VOR identifier and frequency) noted on the airport diagram in your question represents a "VOR Aerodrome Checkpoint Marking" (Source: ICAO-Annex-14-Volume-1-Aerodrome-Design-and-Operations). You can scroll from the Source document to the pages and figures shown in the images below for additional information:
(highlighting is mine)