Oil prices are falling for the second session after China's GDP data turned out to be weaker than expected. Brent crude fell 1% to $79.11 a barrel. WTI also falls 1% to $74.64 a barrel. Oil prices tumbled after China's second-quarter GDP growth was 6.3%, below forecasts for growth of 6.9%. Oil prices are also under pressure from reports that some closed oil wells in Libya have reopened. China, the world's second largest economy and a major consumer of commodities, weaker-than-expected Chinese GDP "is likely to continue to worries markets."