By Michael Erman

Nigerian senior oil workers union and Chevron are expected to resume talks on Thursday in a last-ditch effort to avert an all-out strike that could sharply cut output from the world's eighth largest exporter.

Oil fell more than $2 on Wednesday after U.S. weekly data showed crude inventories in the world's top consumer rising as high fuel prices continued to erode demand.

The record run-up in oil prices over recent years is igniting fierce debate over the "peak oil" theory — that once the maximum rate of global production is reached, a steep decline ensues.   Here we present two squarely opposed viewpoints on the issues from rivals who have been sparring for years. 

Not long ago, it was hard for retail investors to play the oil patch. Not anymore. As the energy bull market rages on, investors looking for a piece of the gains in oil and gas (and alternative energy) need only select from the dozens of energy-oriented Exchange Traded Funds (ETFSs) that are cropping up to meet demand.

Geothermal power has not only been getting investor attention recently, but it can lay claim to being perhaps the oldest of renewable energy sources.  It is also genuinely renewable. Estimates vary considerably, but all say the potential is vast compared to what exists today.

With the proliferation of energy-oriented mutual funds over the last ten years, getting a piece of this supercharged, if highly volatile, sector has never been easier. But energy funds have been notoriously hot and cold over the years, so investors should allocate no more than 5 percent of their total portfolio to this sector.

Stocks tumbled Wednesday as oil's resurgence lit the fuse of inflation fears, pushing the Dow to a three-month low.  Oil jumped about $5 a barrel, settling at $136.38. Financials were the hardest hit.

The Dow plunged more than 400 points as the sharpest jump in the unemployment rate in more than 20 years and rocketing oil prices sparked concerns about stagflation. Oil jumped more than $11 a barrel to close at a record $138.54.

Russia is a safe country for foreign energy companies to make investments and doesn’t use natural-gas prices for political purposes, the deputy chairman of energy giant Gazprom said in an exclusive interview on CNBC’s "Closing Bell."

Markets aren't stagnant today, and your portfolio shouldn't be either. To give investors an edge, CNBC asked the market experts for their best stock picks now.

With billions of dollars now moving into geothermal energy projects around the world, it is no longer a marginal business, meriting a second look by investors looking for a clean technology subsector with significant upside potential.

Chevron, the second-largest U.S. oil company, said Friday its first-quarter earnings rose 10 percent as record oil prices outweighed weak profits from gasoline production.

Headline themes ran through Wednesday's stock chatter on CNBC: Food inflation, oil and defense against economic turmoil. Click for analyst insights and recommendations.

Oil stocks are shooting up like geysers -- but which ones should you buy? Jason Gammel, senior oil analyst at Macquarie Capital, and Tina Vital, integrated oil & gas analyst at S&P, agree on two stocks -- for different reasons.