Big Blue Painting

Hi all.

This painting is 47" wide and 33" tall. It's on thick , coarse canvas or jute. The tacks are copper. The stretchers have an insignia and "Glendale NY" which I think means they're made by Anco. No signature or writing anywhere.

AI says it's a period piece of abstract Expressionism, Color Field painting in the style of Clyfford Still, particularly his painting known as 'Big Blue.'

I'm wanting to see what all you think.

Thanks in advance.

Found in a thrift store in Portland, Oregon.