Oil prices resumed their descent Friday, dropping below $117 a barrel as a strengthening dollar and expectations of slowing demand offset supply concerns over a sabotaged pipeline in Turkey. Light, sweet crude for September delivery slumped $3.43 to $116.58 a barrel in morning trading on the New York Mercantile Exchange, after dipping as low as $116.10. Analysts have pointed to the $117 a barrel mark as technically significant - a move below this level shows, they say, that oil's recent slide might be more than a brief pullback. Crude peaked at $147.27 on July 11. Oil had risen $1.14 Thursday to close at $120.02 a barrel after Turkey's state-run news agency Anatolia said the pipeline, attacked by the separatist group Kurdistan Workers' Party, could be shut down for up to 15 days. The pipeline can pump slightly more than 1 million barrels of crude oil per day, or more than 1 percent of the world's daily crude output.