Monday morning, Halliburton (NYSE:HAL) posted solid fourth-quarter results — 37% sales growth, 47% earnings growth — beating consensus analyst views despite political unrest in the Middle East.

These earnings were driven by strong revenue growth and increased drilling activity due to rising crude prices. The company expects activity to continue to accelerate in 2012.

However, margins were slightly weaker than expected, and Halliburton hinted that the New Year could bring a potential rise in material, labor and logistics costs.

Halliburton is an oil-and-gas equipment and services company, and though I don’t recommend HAL, I do recommend several other companies in the sector. In fact, my emerging-growth portfolio is heavily weighted in best-of-the-best oil companies benefiting from higher crude prices and the fracking boom here in the U.S.

We’ve seen some volatility in the energy market in recent weeks due to the narrowing spread between Brent crude and West Texas Intermediate. I’ve been keeping a close eye on developments on that front, and so far I haven’t noticed any major red flags.

Right now, energy stocks are a screaming buy. The ride higher will be bumpy, but the trend is firmly up. Keep in mind that the roller-coaster ride we experienced in 2011 — chaos in the Middle East culminating with the Libyan uprising, a stronger dollar and eurozone contagion fears. I expect this volatility to continue in 2012. We’ve already seen the drama as Iran blusters about the Strait of Hormuz, where a third of the world’s oil tankers pass.

But these oscillations should be treated as buying opportunities, and I expect oil-related holdings to surge higher as investors bid up shares in the coming months.