LONDON, July 27 (Reuters) - Barclays reported a profit for the first half of the year that met expectations on Thursday, as its booming consumer and credit card business continued to offset plunging revenues in its investment bank as corporate dealmaking stalls.

The British bank reported pretax profit of 4.6 billion pounds ($5.96 billion) in line with the average analyst forecast of 4.5 billion pounds, and higher than the 3.7 billion pounds it delivered in the same period a year ago.

Barclays' results highlight a shift in the fortunes of global banks' business lines, as investment banking and trading suffer from turbulent markets and dwindling client demand while more staid areas such as retail and corporate banking benefit from rising interest rates.

Barclays reported a 10% drop in income at its investment bank, with income from its fixed income, currency and commodities division down by 6% to 2.97 billion pounds and income from its Equities unit tumbling 49% to 1.3 billon pounds.

U.S. banking giants such as Goldman Sachs and Citigroup earlier this month reported lacklustre results for investment banking, albeit rival JPMorgan's CFO Jeremy Barnum said he saw green shoots emerging in areas like stock offerings that had withered in the last year.

Barclays also announced a share buyback of 750 million pounds for the second quarter, more generous than the 575 million pounds average of analysts' forecasts as compiled by the bank.

Several investors told Reuters earlier this month they wanted the bank to prioritise returning more capital to shareholders instead of investing it, after the lender completed a modest 500 million pound buyback in April.

Rising interest rates in Barclays' key markets of the UK and United States have boosted its income, but they are also squeezing borrowers and increasing the risk of loan defaults.

The bank set aside 896 million pounds in the six-month period for potentially soured loans, more than double the 341 million pound charge the previous year.

($1 = 0.7724 pounds) (Reporting By Lawrence White and Iain Withers, editing by Sinead Cruise)