Doesn't seem to be anything atm. Thousands of bitcoins were sold in a short moment that caused the sudden drop from $7800 to $7100. Whoever sold that 5000 btc on Bitfinex in a single swoosh seemed to have wanted to take profits but crashed the market instead. Anyways, price is slowly going back to $7300 right now yet it still amazes me how a few thousand coins can actually crash a market that hard.
Was looking for a good explanation and I saw your post, one very interesting thing you note is how few thousands of dollars can crash the market, this is very true, one or a group of whales can make an impact, my take is this is a group of guy who wants to make a profit and the price at $8000 level is a good level to sell some.
This can happen from time to time take note of this.