PeopleChevron simplifies organisational structure and consolidates value chainAt least two long-time employees will retire with the changesOrganisational changes: Chevron, headed by chief executive Mike Wirth, will consolidate its upstream business into two categories for Amnerican and international exploration and productionPhoto: PHIL MCCARTEN/CORPORATEEVENTIMAGESNaomi KlingeHouston