market depth

I would appreciate any comments on the market depth on the SPI. It is so loaded on the buy side yet the orders are being filled so it seems obvious to me that they are not props. I've never seen it like that except for quarterly options expiry maybe.

Whenever I do see large orders I know that more often than not the MIB will push the price until their orders get filled but as these huge orders are filled more just come on board.

If we were on a low I would think it reasonable with short covering, and buying in anticipation of a bounce, but when the market has reached the 50% fib level and is looking tired, and it is Feb. (March often being tricky) and, at the very least, looks like it needs to take a breather before moving on up again I just don't understand it.

TIA