Shares in San Leon Energy surged after the oil and gas company said it had successfully completed the hydraulic fracture of a well in the Baltic Basin.San Leon said United Oilfield Services completed the operation on Tuesday at the Lewino-1G2 well in Gdansk W Concession. The operation achieved a main treatment pump rate of 120 barrels per minute at pressure, the highest achieved outside North America, San Leon said.San Leon shares rose more than 11 per cent and were trading up 7.6% at 5.40p.San Leon executive chairman Oisin Fanning said: "We are very satisfied with the initial results achieved by this operation. A high rate was an integral part of our frack design and to achieve a rate at the top end of that spectrum is very encouraging."