LONDON -- This week has seen the price of oil move energetically upward before falling back again, with both main crude benchmarks peaking on Thursday. Brent crude briefly breached the $116 level before settling back to around $115, while West Texas intermediate crude came close to $98 per barrel before dropping back to around $96 when U.S. markets opened this morning, leaving it almost unchanged on the week.

Natural gas prices have held onto their gains more successfully this week, with the Henry Hub price rising from around $2.70/mmbtu on Monday to $2.81/mmbtu on Friday morning, a gain of 4.5%.

As a result, the United States Oil Fund was up by 0.6% when U.S. markets opened today, while the United States Natural Gas Fund was 1.8% higher.

High oil prices are continuing to support the share prices of small oil companies, and this week has seen some massive share price moves. I've highlighted three of this week's top performers below:

Borders & Southern Petroleum
Borders & Southern Petroleum (LSE: BOR.L) rocketed 82% to 33 pence this week. This phoenix-like rise was due to the company releasing its long-awaited analysis of the fluid sample taken from its Darwin exploration well. Borders also reported a mid-case recoverable volume of 190 million barrels of condensate from Darwin -- although its commerciality remains uncertain.

Heritage Oil
Heritage Oil (LSE: HOIL.L) rose by 18% to 200 pence this week. The company's shareholders were initially disappointed that the company's Miran find was mostly gas, but those that kept the faith were rewarded this week when Heritage announced a double whammy, monetizing Miran with a farm-out to Genel Energy while using the remainder of Miran to secure a loan from Genel, preventing it from needing to use a dilutive equity issue to pay for its recent Nigerian acquisition, OML30.

Advantage Oil & Gas
Advantage Oil & Gas (NYSE: AAV) surged 13.5% to $3.70 yesterday after revealing that it is planning to sell noncore assets and prepare the company for a sale. Advantage fell heavily recently after disappointing quarterly results. The Calgary, Alberta-based company has 1.1Tcf of proved and probable gas reserves in Canada's Montney shale formation, output from which is being lined up to supply a proposed LNG export facility.

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