close up sliver surface or other ways to close the gap?

Hi,

As shown from the model, I created complicated boundary blends in order to close the gap in the model, I tried to let all surfaces enclosed and then solidify it but there is some tiny sliver surfaces that prevent me from doing that (some yellow edges in wire-frame mode). Is there a way to close up sliver surface? I also feel my method is not good enough, other methods that can close the gap are also helpful

Thanks

Gubing