top of page

Saturdays attempt to identify rocks in the Great Lakes:: Conglomerates

Saturdays post for Rock identification. Conglomerates!

Conglomerates are defined as a sedimentary rock with other rocks cemented together in a finer grained quartz matrix. Conglomerates are approximately 2 to 4 billion years old. There are many different subcategories to conglomerates as well depending on the area it was found. Categories like Jasper puddingstone, Roxbury pudding stone, Fairburn conglomerate. Each place will have a different version of matrix and different stone inclusions.

The most obvious conglomerates are gowganda tillite and the pudding stone. Pudding stones are best know for the red and brown jasper in the matrix. One of the biggest mistakes for conglomerates is concrete. Although technically still a conglomerate. The way to tell the difference......concrete is more grainy and not as dense. Then there is asphalt. (Still technically a conglomerate) Conglomerates have a wide variety of colors and stones trapped in the matrix.

I hope this is helpful. I am not an expert, just trying to learn with you. And my pics are limited. If you would like to chime in with more information or you would like to share some pics......please do! Feel free to share! There is no such thing as a bad day at the beach! Have an Awesome day!

20 views0 comments


bottom of page