EOG Resources (EOG 0.46%) continued to demonstrate its drilling prowess in the second quarter: It once again beat its production targets, with its oil output growing to a new record of 384,600 barrels per day. On the back of those gains, the company earned an adjusted $1.37 per share, which beat analysts' expectations by $0.14 per share. However, as only EOG can do, it overshadowed its exceptional operational and financial results by unveiling three pleasant surprises that are even bigger stories for investors.

1. The dividend acceleration has begun

EOG Resources made it clear when it delivered its Q1 results three months ago that it planned to accelerate its dividend growth, which had been clocking in historically at a 19% compound annual rate. So while the company gave investors a 10% dividend increase back in February, investors had reason to expect another hike was on the way.

The sun shining behind an oil pump.

Image source: Getty Images.

Sure enough, the company announced its second dividend increase of 2018 in conjunction with its Q2 earnings release. However, what was surprising was its size: The company boosted the payout by 19%, bringing its year-to-date increase to 31%. While the stock still has a low yield even after that raise, EOG aims to keep moving its payout upward at a fast pace in the coming years.

2. Two more high-return discoveries

A major driver of EOG's success over the years has been its exploration prowess: The company has a track record of uncovering new high-return shale plays in the U.S. It continued to do so in Q2, when it unveiled not one but two new additions to its inventory of premium-return drilling plays -- locations that can earn a 30% after-tax rate of return at $40 oil.

The company announced that recent drilling results in the Mowry and Niobrara shale plays of the Powder River Basin confirm that these two formations have the oil resources to earn high returns on capital. EOG verified this belief by completing five Niobrara wells over the past two years that not only delivered strong initial results but have been very productive since coming online. Meanwhile, two recent Mowry wells both achieved strong initial results.

Based on these results, EOG estimates that it can drill 875 more premium-return Mowry wells, and another 555 into the Niobrara across its acreage in the Powder River Basin.

Drilling rigs in the mountains.

Image source: Getty Images.

3. A game-changing oil resource

Before making the discoveries mentioned above, EOG Resources' 400,000-acre Powder River Basin position consisted of 120 undrilled premium locations in the Turner Sand formation, which held an estimated 190 million barrels of oil equivalent (BOE) resources. These discoveries dramatically expanded that position. The company now estimates that it has 1,845 premium drilling locations in the region after adding the Mowry and Niobrara sites, as well as boosting its Turner Sand count by 200. That's a large enough inventory to support 30 years of drilling at the company's current pace in the region. Further, the company now believes this position holds 2.1 billion BOE of recoverable resources, which is a jaw-dropping 1,000% increase from its initial estimate. That vaults its Powder River Basin holdings past its Bakken Shale acreage as the company's third-largest asset, behind its Delaware Basin and Eagle Ford Shale positions. Overall, EOG's shale portfolio now boasts 9.2 billion BOE of resource potential, and 9,500 remaining premium-return drilling locations.

EOG's discoveries in the Powder River Basin bode well for other oil companies looking for new shale plays in the area. Chesapeake Energy (CHKA.Q) stated in its second-quarter earnings release that the Powder River Basin was "quickly establishing itself as the growth engine of the company" thanks to the strong drilling results it has seen from wells in the Turner formation. Because of that, Chesapeake currently has five rigs operating in the area, all of which it has primarily focused on the Turner. However, the company noted that it's exploring the potential of adding a sixth rig next year, which could enable it to target other formations in the region such as the Mowry and Niobrara. EOG's results in those two plays are cause for increased optimism that Chesapeake could also be sitting on a massive oil and gas resource in the region.

Meanwhile, Devon Energy (DVN 0.74%) recently started exploring the Niobrara after finding success in the Turner. It's in the process of completing two wells in that formation, and should reveal their results later this year. If they're successful, the Powder River Basin could become a third growth driver for Devon.

EOG's exploration efforts continue to pay off for shareholders

EOG Resources has avoided making splashy acquisitions, instead focusing on exploration to drive growth. That has been a wildly successful approach, and the proof was on full display in Q2. Those new additions to an already-impressive portfolio should give the company the ability to continue growing both production and its dividend at high rates for years to come.