Complex sentence: He was also a founder, in 1952, of the Geological Society of Australia of which he was president 1955-56; the society awards the W. R. Browne medal as its highest honour.
Split into simpler sentences: He was also a founder, in 1952, of the Geological Society of Australia of which he was president 1955-56. The Society awards the W. R. Browne medal as its highest honour.