Calvalley Petroleum Inc. is an international oil and gas company based in Calgary, Alberta and London, England which is focused on exploration and development of Block 9 in the Republic of Yemen. Calvalley's common shares are listed on the Toronto Stock Exchange under the symbol "CVI.A."
Calvalley's principal assets and operations are related to its 50% working interest in the Production Sharing Agreement for Block 9, which consists of 2,234 km2 (552,000 acres) of land within the prolific Sayun-Masila Basin. Calvalley has made several significant hydrocarbon discoveries on Block 9. Calvalley declared commerciality during 2005 and started commercial production in December of that year.
Since 2005 the company has grown its reserves and production base. At the end of 2013, the company's interest in crude oil reserves was 23 million barrels of oil and the annual average production volume for 2013 was 2,516 bpd, the highest annual average since 2007.