When it comes to the energy sector, no one can really compete with the supermajors. Their sheer size, proven reserves and technological expertise puts them in a league of their own. Adding in their huge cash flows, capital appreciation and strong dividends, and it’s easy to see why they’ve been great long-term investments for those looking to add energy exposure.

Perhaps none have rewarded shareholders over the long haul more than American giants Exxon Mobil (NYSE:XOM) and Chevron (NYSE:CVX).

Of course, past performance is just that — in the past.

What investors really want to know is which is the better buy today. Now that Q1 earnings are in the rear-view mirror, we’ve got a clearer picture to work with.

A Look at Q1

The most recent quarter was a mixed bag for both majors, and variability in the energy markets affected XOM and CVX in different ways.

Exxon Mobil reported a fractional year-over-year earnings improvement in Q1 to $9.5 billion, or $2.12 per share, easily clearing Wall Street expectations for EPS of $2.05.

As usual, Exxon’s earnings were defined by the company’s integrated nature.

Much like last quarter, refining and chemical production saved Exxon’s day in the face of lower oil prices. During the past few years, Exxon’s Gulf Coast refineries have more than tripled the amount of cheaper WTI crude they use to produce gasoline, diesel and jet fuel. Juicy cost savings result in juicy margins, and Exxon was able to sell those cheaply produced chemicals and fuels around the world at enormous profits. Earnings at Exxon’s global chemicals facilities grew 62% in the quarter to $639 million, while U.S. refining profit jumped 72% to $1 billion.

However, Exxon did suffer from falling production — a long-term trend for the giant. XOM produced 3.5% less oil and gas in the first quarter. Last year, production fell by 5.9%, and Exxon predicts its global output will fall 1% this year. That’s a big issue considering the company’s size and has led to speculation that Exxon will soon have to pull out its checkbook and make a big acquisition.

Growing production doesn’t seem to be a problem for rival Chevron.

The second-largest U.S. oil company slightly boosted output of oil and gas to 2.65 million barrels per day from 2.63 million last quarter. That gain in production even comes after the shutdown of an offshore Brazil platform following two spills last year. Chevron hopes to increase production by 25% to 3.3 million barrels per day by 2017, as it’s currently developing 66 different hydrocarbon projects around the world.

However, that reliance on energy production cost Chevron a bit this quarter. Because a big part of its production mix is oil, Chevron saw a 4.5% fall in profits amid a drop in crude oil prices during the first three months of the year. Overall, CVX reported an average sale price per barrel of $94 in the U.S and $102 abroad, down from $102 and $110, respectively.

Chevron also struggled on the refinery side of things. Refinery output fell 38% to just 576,000 barrels per day. While some of that can be attributed to maintenance and upgrades, as well as repairs on its Richmond California refinery — which caught on fire last year — Chevron has been looking at divesting and selling some of its global chemical operations in recent years. While not completely going the ConocoPhillips (NYSE:COP) route, CVX has put some of its operations for sale.

Overall, Chevron reported earnings of $3.18 a share — a YOY decline of 4%.

What XOM and CVX Provide

The different paths the two firms took to profitability should give investors some indication of what’s in store for the future — depending on what you’re looking for in your oil and gas investment.

Exxon is starting to look like a plodding dinosaur — not that there’s anything wrong with that. Refining can be a steady generator of cash when a conditions are great, and Exxon continues to produce huge amounts of cash flow. However, an energy company’s bread and butter is energy production. With that, Exxon’s drop in production is starting to become worrisome; this is now the umpteenth quarter in which downstream has been the shining star.

While Exxon has more than 28 major oil and gas projects — including around 24 linked to oil and liquids production — set to start pumping between now and 2017, the company ultimately will have to grow its reserves and production by opening up its wallet. Until then, investors are going to deal with stagnating production growth.

On the flip side, Chevron is the production champ of the two. As such, CVX seems to be ensuring its investors’ futures more by increasing what it pulls out of the ground each year. However, that reliance on oil does bend to the whims of global prices more than its refining-focused rival. Investors are compensated for that risk with a higher dividend yield and higher returns. Chevron appreciated 9.9% during the last three months, while Exxon advanced just 4.1%.

Bottom Line

So, which is it?

I’d have to side with Chevron right now. It seems to have all the components to make it the top choice of the supermajors, and it’s currently the better income play.

That said, Exxon is no slouch. Once it opens its wallet — and it will — you can guarantee that what it buys will be transformative. And investors will be the better for it.

As of this writing, Aaron Levitt did not hold a position in any of the aforementioned securities.