In a previous version of this article, the author stated the Papa-Terra project between Chevron and Petrobras was located in the Gulf of Mexico, when in fact the project is off the coast of Brazil. The Fool regrets the error. 

This month marks three years since the Obama administration lifted the five-month moratorium on deepwater drilling in the US Gulf of Mexico after BP's (BP 0.71%) tragic Deepwater Horizon oil spill.

Even after the ban was lifted in October 2010, oil and gas drilling activity in the Gulf remained heavily subdued, as companies proceeded with caution in the aftermath of the worst accidental oil spill in history.

But this year, drilling activity has finally rebounded, as evidenced by the surge in operated rigs and the number of drilling permits issued in the region. With activity expected to accelerate further in coming years, let's take a closer look at two energy companies making a splash in the US Gulf of Mexico.

Shell
First up is Royal Dutch Shell (RDS.A), currently the most active Gulf operator. Just this year alone, the Hague-based energy giant has bid $144 million for Gulf acreage and has already been awarded seven permits to drill new wells.

The company is getting ready to commence the final stage of a $2.5 billion venture at its Auger platform, which will tie in production from wells located in the Cardamom field -- a high-margin deepwater field slated to come on stream by 2014 and expected to produce about 50,000 barrels of oil equivalent per day at peak production.

Though Shell saw a production decline from its Gulf of Mexico deepwater business in the second quarter due to delays and downtime, its output from the region should rise substantially next year and in 2015, as major projects such as Mars-B and Cardamom come online. 

Combined, these projects should deliver production of 170,000 barrels of oil equivalent per day, which is more than Shell's total production of 177,000 barrels oil equivalent per day during the second quarter. As such, investors can expect Shell's Gulf of Mexico operations to remain a vital component of its global portfolio and to account for a significant portion of the company's oil production and cash flow growth over the next few years.

Chevron
Next is Chevron (CVX 1.04%), which recently made a major deepwater oil discovery in the Gulf's Coronado prospect roughly 200 miles off the coast of Louisiana. While Shell and BP may have Chevron beat in terms of the number of permits awarded this year, the San Ramon, California-based energy giant has a truly massive portfolio of Gulf projects that are either already in production or will be shortly.

The combined output from these projects, which include Jack/St. Malo, Big Foot, and Tubular Bells and are slated to begin production by 2014, should boost Chevron's total production tremendously. Jack/St. Malo is expected to produce a whopping 177,000 barrels of oil equivalent per day, of which 88,500 barrels of production would be net to Chevron. 

Along with its operations in North America, West Africa, and Australia, this project will be crucial in helping Chevron meet its production target of 3.3 million barrels of oil equivalent by 2017.

The bottom line
While Gulf oil output is still about a third below highs attained in 2009, it is poised to grow rapidly in the coming years. According to consultancy Wood Mackenzie, Gulf production will reach 2 million barrels of oil equivalent per day in 2018-2019, driven by oil majors like Shell and Chevron that have the requisite capital and experience to operate in an environment as harsh and technically complex as the deepwater Gulf of Mexico.