Just over four months after an explosion on BP's Deepwater Horizon rig caused the largest oil spill in history, tensions are running high with the news of another offshore oil rig blast.

Though many details have yet to emerge. It's not clear if the rig was drilling or idle or what caused the fire, though all 13 workers on board survived with one injured.

About the only concrete news to come out is that the rig is owned and operated by Houston-based Mariner Energy. But just who is Mariner?

Incorporated in 1983, Mariner has a drilling portfolio of 150,000 acres in the Permian Basin and 350 Federal offshore leases in both the continental shelf and deep water. The company has 328 employees, the vast majority of which are in the Houston headquarters, and posted a net income of $17 million in the first two quarters of 2010.

President and CEO Scott D. Josey's tenure dates to when Enron — where Josey was a vice president and managed the Energy Capital Resources group — had a controlling stake in the company.

Mariner's website includes information about their exploration, growth and acquisition models, including that:

The explosion of rig Vermilion 380 could complicate a pending merger between Mariner and Apache Corporation. The deal was announced in April for Apache to purchase Mariner for $2.7 billion, giving Apache its first access to oil deposits in the Gulf of Mexico. But that figure assumes a Mariner stock price of $26.22, and after news reports of the rig fire the stock is already down more than four percent

In July, Apache also purchased fields from cash-hungry BP in West Texas, Canada and Egypt for $7 billion.