Chemical company Stepan Company said Friday it formed a global joint venture with Nalco Holding Company to market chemicals designed to increase crude oil and gas production from existing fields, the Associated Press reported on Friday. Stepan said a dramatic rise in crude oil prices has created renewed interest in the enhanced oil recovery technologies. The joint venture will operate under the Tiorco brand. It will provide sales and service using Nalco''s global reach in upstream energy markets and expertise, as well as Stepan''s global surfactant technology and manufacturing capabilities. The joint venture will be equally owned and controlled by Nalco and Stepan.