Walsh took over Oct. 1 from Mark Nelson, who has moved on to become president of Chevron Canada Ltd. and vice president of CNAEP, its upstream exploration and production business.

Also newly appointed at the company is Martha Marty Gilles, who in September was named vice president, global base oil. Andrew Tong, who previously held that position, has been assigned to manage Chevrons newly formed Business Architecture and Integration group.

Gilles holds a degree in civil engineering from Colorado State University and has over two decades of refining experience, with extensive technical, environmental and operational background at Chevron refineries. She served as business unit manager of the Richmond, Calif., lube oil plant (RLOP), and was responsible for the production of base oils there. In her role as general manager of the Hawaii refinery on Oahu, she steered the plant through a major FCC upgrade and refinery turnaround. Most recently Gilles was downstream advisor, coordinating the staff activities for the head of Chevrons downstream organization.