Harris joins South32 from JCP Investment Partners, a Melbourne-based fund that has over $10 billion of Australian equity assets under management.
As a partial owner of the fund, Peter was responsible for mining, energy, utilities and steel sector investments.
He takes up the role at South32 from Monday February 23.
Blaney joins the South32 team from Citi, where he is currently md/head, corporate and government affairs, Australia and New Zealand.
He will take charge on Tuesday March 24.
Harris and Blaney will be based in South32’s office in Perth.
A BHP shareholder vote on the proposed demerger will take place in May.