The second circuit-breaker was issued at 1004 GMT, with the benchmark BIST-100 index down 7.01% and the banking index down 6.41%.
The stock market said trading was due to resume at 1034 GMT. On Monday, the BIST-100 tumbled as much as 4.99% before circuit breakers came into effect, suspending trading in dozens of shares, and trading volumes remained at a fraction of last week's average at 21 billion lira ($1.12 billion), according to a research note from Ziraat Yatirim. The magnitude 7.8 quake that hit Turkey and Syria early on Monday toppled thousands of buildings and left thousands of people injured or homeless. The total death toll in the two countries had surpassed 5,000 by Tuesday, after Turkey declared 3,419 dead. ($1 = 18.8285 liras) (Reporting by Gdansk newsroom; Editing by Susan Fenton and Mark Potter)