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The rock is approximately 12cm in length and from what I can tell this is a sedimentary rock and is a conglomerate. I'd say it was from a high energy environment due to the round gravels. This is all I can tell from looking at this, but I need more information about this rock.

For instance:

-What is the likely environment the rock was formed in

-rough grain size

-etc (other main important features)

Thanks.

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closed as off-topic by Leukocyte, Gimelist, uhoh, Fred, Semidiurnal Simon Aug 27 at 19:17

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One really needs to examine a rock under a polarizing microscope to say very much about its composition and history. As you rightly say, it's very obviously a medium to high energy conglomerate. Judging from the heterogeneous lithology of the individual rounded particles, one might infer that it is a fluvial sedimentary environment, such as an alluvial fan, downstream of a varied geological terrain in the upstream source area.

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This rock is most definitely a conglomerate. The grain size appears to be bimodally distributed with pebble sized clasts in a coarse sand matrix. The grain shape for the clasts appears well rounded and a medium sphericity. A quantitative analysis of grain size can be obtained by randomly selecting grains and measuring them (both the clasts and the matrix).

The environment was a high energy one, but there has been some transport from the source as the clasts are well rounded. It appears sorted as well, so the sediment was transported by a fluid. The environment was likely fluvial.

The sample is from a core. If you have a more complete core it would be useful in determining a more exact depositional environment.

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