What happened

Shares of ConocoPhillips (NYSE:COP) continued rallying last month, rising another 10%, which put them up more than 40% over the past year. Fueling April's surge -- which added more than $7.5 billion to the company's market cap -- was a combination of higher oil prices, another oil discovery in Alaska, and strong first-quarter results.

So what

Crude prices continued their unabated rebound last month and hit a three-year high due to continued strong demand amid OPEC's efforts to keep a lid on supplies. Overall, the global benchmark, Brent, rose 7.7% to nearly $75 a barrel, while WTI, the U.S. oil benchmark, rose 5.6% to about $68.50 a barrel. Those higher oil prices are excellent news for ConocoPhillips since it positioned its business to cash in on $50 oil.

A beam of light shining through an oil pump at sunset.

Image source: Getty Images.

That was evident in the company's first-quarter results, which crushed analysts' expectations. The company did so by producing more oil than expected thanks to strong results from its big three unconventional assets -- Bakken shaleEagle Ford shale, and Delaware Basin -- where output jumped 20% year over year. Add those strong drilling results to the company's ability to keep a lid on costs amid higher oil prices and adjusted earnings topped $1.1 billion, which was up significantly from the year-ago quarter when it turned in an adjusted loss of $0.2 billion.

Another highlight last month was the results of the company's Alaskan exploration program. ConocoPhillips completed six appraisal and exploration wells in the state, each of which encountered oil. Three of those wells further confirmed the potential of its Willow discovery of at least a 300 million barrel of oil resource, while the others resulted in new finds for the oil giant.

Now what

ConocoPhillips' stock has been red-hot over the past year due to the success of its plan to create value through a combination of high-return growth and increasing cash returns to investors. While the stock is no longer as cheap as it once was, ConocoPhillips could still have ample upside from here given the cash its business can produce at current oil prices, a growing portion of which it will likely return to investors via share repurchases and the dividend.

Matthew DiLallo owns shares of ConocoPhillips. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.