LONDON (Reuters) - Shell's adjusted earnings, its definition of net profit, reached $4.264 billion in the second quarter, it said on Thursday, above the $3.74 billion average in an analyst poll provided by the company but down from $6.3 billion a year ago.

Shell said it would maintain the pace of its share buyback programme at $3.5 billion over the next three months, the 15th consecutive quarter of at least $3 billion.

Shell had guided in a trading update earlier this month that it expected quarterly earnings to be hit by weaker trading in its integrated gas division and losses at its chemicals and products operations.

Global benchmark Brent crude prices averaged around $67 a barrel during the April-June quarter, compared with $75 a barrel in the first quarter and $85 a year earlier.