By Jim Jelter
SAN FRANCISCO (MarketWatch) -- Oil and gas stocks tumbled at the open Thursday, joining a broad market retreat with no support from underlying commodities to halt the slide. Independent producers were posting the biggest declines, with Anadarko Petroleum APC -1.55% , Hess HES -1.33% and Occidental Petroleum OXY -1.24% each down about 1%. Information on energy operations along the Gulf Coast from Hurricane Isaac are still sketchy, but reports so far indicate no serious damage. The NYSE Arca Oil Index XX:XOI -0.72% was down 0.5% at 1,224 points, the NYSE Arca Natural Gas Index XX:XNG -0.95% was off 0.8% at 634 and the Philadelphia Oil Service Sector Index OSX -1.44% was down 1.7% at 219 points. October crude-oil futures were off 74 cents at $94.78 a barrel in New York.
