If you mean the OPEC thing: this really is a wild guess, I'm not convinced in the least. And insane volatility of Bitcoin is old news, anybody who said otherwise obviously never looked at the trading charts in his whole life. In fact, it's volatility is the main real reason it's interesting to the majority of BTC users: they only need it to speculate. Nobody really buys anything for BTC.

And other cryptocurrencies are still very much tied to BTC, so when BTCUSD falls dramatically, they do as well.