What: Shares of oil services company Tetra Technologies (TTI 0.29%) are up 15% at the time of this writing, after it posted better-than-expected results and raised its guidance for the rest of the year in its quarterly earnings report, issued before the market opened.

So what: This quarter, Tetra's $0.16 earnings per share beat Wall Street expectations by $0.15.

What really was impressive is that the company was able to significantly grow revenue and margins in its most important segment: completion fluids. Revenue in this segment only increased a little more than 5%, but the 91% uptick in net income was what really wowed, thanks to reduced costs that expanded the segment's margins to 26.6% from 14.6% the year prior. The strength of this segment was also able to make up for the losses it incurred in weaker segments such as its Production Testing and Offshore Services segments, which both saw declines in revenue and operational profits. 

Another aspect that seemed to have captivated investors is that the company actually increased its guidance for the next quarter to $0.07-0.09 per share, up from analyst expectations that had Tetra's third-quarter earnings coming in at $0.02 per share.

Now what: There have been quite a few oil services companies that have beat expectations this quarter, which is probably more an indication that analysts had pretty low expectations for the quarter than anything else. Tetra just became the next one on that list thanks to these rather impressive results in what some might call a dismal business environment. However, if it can continue to crank out results like these over the next couple of quarters, then chances are this stock could be worth watching.