On Bitstamp, BTC-e, and Bitfinex, there was a surge in volume (peaking at 300-700 BTC/min) while the price was shooting up, but when the rally stalled then volume dropped again to the very low levels it had before (10-30 BTC/min).
On Huobi and OKCoin, volume surged to about the same levels (~600 BTC/min) during the rally, but then it remained high (~120 BTC/min) while the price wandered between ~3800 and ~3820.
Need I say that I see that as evidence that the rally happened in China, and the trades in the West were mainly arbitrage?
Why are you so obsessed with the Chinese having to lead the exchanges? Its clear that stamp/finex led this based on how much they moved up (15-20 $) while huobi went up around $10. The volume can easily be explained by the fact that the chinese exchanges have no trading fees. As an example some Chinese traders may be selling during the rally to buy back a few minutes later at a little lower price, which isn't as easy if there are trading fees that will cut into profit.