United States crude production fell for a second month in November because of a drop offshore, but higher output from the biggest shale states highlighted the industry’s surprising resilience. Production nationwide in November dropped 52,000 barrels a day to 9.32 million, the lowest figure since June, according to data from the Energy Information Administration’s petroleum supply monthly report. In absolute terms, the number reported on Friday was much higher than the 9.05 million in agency forecasts. The data, though two months in arrears, is considered a critical indicator for traders and analysts who are trying to understand when a long-running shale boom will lose momentum. A global oil glut has sent prices to nearly 13-year lows; though on Friday, Brent crude, the global benchmark, gained 2.5 percent.