By Catherine Carlock Oil and gas stocks clung to slim gains early Friday, holding their ground as crude-oil prices moved lower. For the week, however, the sector is looking at declines of 4% or more. The NYSE Arca Oil Index rose 0.3% to 882.46 points. Anadarko Petroleum Corp. (APC) led the index's percentage gainers, up 2.2% at $38.00. French oil group Total SA (TOT, FP.FR) was up 1.9% at $45.94. The company said Thursday it is necessary for companies to drill in deepwater oil fields despite the moratorium on the Gulf of Mexico, because oil prices would soar otherwise, according to a report published by Susquehanna Financial Group. The moratorium stemmed from the April 20 explosion of BP PLC's (BP, BP.LN) Macondo well, which is still leaking between 35,000 and 60,000 barrels of oil per day. The NYSE Arca Natural Gas Index was up 0.3% at 481.26 points. NiSource Inc. (NI), a natural-gas producer and utility company, led the index with a 2% rise to $14.66. The Philadelphia Oil Service Sector Index rose 1% to 166.63 points. Rowan Companies Inc. (RDC) jumped 4.3% to $22.63 and Halliburton Co. (HAL) rose 2.4% to $25.57. Crude oil for August delivery slipped 32 cents, or 0.4%, to $72.62 a barrel on the New York Mercantile Exchange. -By Catherine Carlock, 415-439-6400; AskNewswires@dowjones.com (END) Dow Jones Newswires July 02, 2010 11:37 ET (15:37 GMT)