Chart, page-400

I think the reasons are actually quite clear. Some 'bad/fake' news triggered a sell off (maybe pushed along by institutions for their own means of a lower buyup), which was grabbed by the shorters and sold down heavily as they saw a good opportunity opening up, which triggered loads of stop-losses (especially those from margin loan accounts), which shoved the SP down faster/harder. As with all momentum, it's now slowed down on market 'exhaustion'. Bulls and bears will fight it out now for a few days. Who knows who'll win - depends on whether any more good/bad news emerges. Otherwise it may drift sideways for a few days. An upward push by bargain hunters will see shorters having to buy to cover, which will push SP back up again, possibly almost as fast as it fell. All fun and games for ST traders, and a pain in the butt for long-uns.

As to how charting takes into account market emotions, if you're interested in TA, I suggest you do some reading. While everyone jokes about the name, the Dummies books are great (see: https://www.amazon.com.au/s/ref=nb_sb_noss_1/358-3226653-7084563?url=search-alias=aps&field-keywords=technical analysis for dummies). Also, anything by Australians Louise Bedford and Daryl Guppy are worth reading, though Guppy's books are a bit old now (though his technical theory is still correct - see: https://www.google.com.au/search?q=Daryl Guppy trading books&rlz=1C5AVSZ_enAU643AU715&oq=Daryl Guppy trading books&aqs=chrome..69i57.6599j0j7&sourceid=chrome&ie=UTF-8).

Cheers GW