LONDON -- In the wider markets this week, a degree of confidence returned, despite ongoing fears of a hard landing in China, continued problems in the eurozone, and disappointing U.S. jobs figures. Oil and gas prices rose slightly, helped by the initiation of sanctions against Iran, which raised fears that crude supplies might tighten.

Both Brent Crude and U.S.-traded West Texas Intermediate rose strongly before settling back to finish the week slightly higher -- around $98.50 and $84.90 per barrel, respectively. These price increases helped lift the performance of the United States Oil Fund (NYSE: USO), which peaked at $32.94 during the week before settling back to about $31.8 for a gain of 3.75% over the last seven days.

Natural-gas prices also rose, helping the United States Natural Gas Fund (NYSE: UNG) outperform its oil-based cousin and gain more than 5% over the week.

While oil and gas prices saw modest gains, some London-traded oil and gas shares managed to outperform the market by a big margin. Here are the three of this week's top performers.

Bankers Petroleum (LSE: BNK.L)
Bankers Petroleum was a standout this week, jumping a massive 78% to 165 pence. The company, which operates the large Patos-Marizna oilfield in Albania, gave a drilling update confirming that a further 29 horizontal wells were completed and placed on production during the last quarter. The company also confirmed that average daily oil sales had risen by 7% to 14,169 barrels in the second quarter and by 14% to 13,724 barrels in the first half of this year.

Lansdowne Oil & Gas (LSE: LOGP.L)
Lansdowne Oil & Gas gained 36% this week, lifting its share price to 46 pence. The cash-strapped Irish Sea exploration company didn't release any new information, but a tender offer to shareholders of SeaEnergy, which has a 25% stake in Lansdowne, may have helped. Also supporting sentiment was the anticipation of the forthcoming resource update from Barryroe -- Lansdowne's main asset -- which could help it resolve a funding shortfall or secure a purchaser.

Gulf Keystone Petroleum (LSE: GKP.L)
Gulf Keystone Petroleum climbed 28% to 210 pence this week, providing a boon to investors in this Kurdistan-focused company. Although the company didn't announce any new developments, news that Kurdistan had started exporting oil directly to Turkey by truck may have helped reassure investors that GKP's 8 billion barrels of oil reserves have a commercial future.

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