I don't know... people claim that SMBIT buys off the exchanges, so those buys should not affect the price immediately. Also, miners create 4000 BTC per day, so those 15 kBTC are 4 days' worth of miners output. Is that enough to start a 100$ rally?
Perhaps the mine disaster in Thailand forced SMBIT or some other entity to buy at the exchanges instead of from those miners.
There was also news of a new NCR point-of-sale terminal that would have native support for bitcoin payments. But that news was not relevant to China, since stores there cannot accept bitcoin, AFAIK.