LONDON -- Oil prices have grown progressively stronger this week as markets respond to reassuring Chinese growth figures and the prospect of further economic stimulus for Asia's biggest economy. Tightened U.S. sanctions against Iran are also helping to keep crude prices firm, as Iran's oil exports have been reduced dramatically from pre-sanction levels.
The result of all this is that the United States Oil Fund (NYSE: USO ) traded robustly this week and was up by 2.2% in morning trading on Friday. It sister fund, the United States Natural Gas Fund (NYSE: UNG ) , fell midweek but recovered to open on Friday down by about 2.7% amid a small rise in natural-gas prices.
However, solid oil and gas prices weren't enough to protect the share prices of some small oil and gas companies, which plunged dramatically. Here are three of this week's worst performers.
BowLeven (LSE: BLVN.L )
BowLeven plunged 14% this week as traders discovered that last week's rumor of a takeover by Tullow Oil was just that -- an apparently unfounded rumor. The company's share price has now returned to its former level of around 60 pence, as there have been no updates from the West Africa-focused group since April.
Aminex (LSE: AEX.L ) fell by 6.2% this week. The company did not release any new information, so the sell-off might have been the result of profit-taking by traders following last week's good news about its Tanzanian gas resources. Despite this week's fall, Aminex is still up 23% on the month.
Rockhopper Exploration's (LSE: RKH.L ) share price slid 3.5% this week. Following news of its 60% farm-out deal with Premier Oil, the company's share price initially rose by more than 10% but ended the week lower as investors sold off the share, having digested the implications of the deal, which will take several years to produce any oil.
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