Tullow shares slump to 20-year low

Tullow Oil shares plummeted by more than 27% to a 21-year low after the Irish-founded exploration company said production from flagship projects in Ghana has disappointed and that it will reassess the commercial viability of recent discoveries made in South America.

The stock sank on the news that crude from two wells in the South American country was found to be heavy, with a high sulfur content. That’s disappointing to shareholders, as the Guyanese discoveries, earlier this year, had countered concerns over troubled ventures elsewhere.