Wednesday, June 29, 2011

Flakestones - a self-explanatory word

I ran into the word flakestone as I was doing some reading on the Trucial Coast tidal flats. And even though the word is pretty self explanatory I wanted to find out what it actually meant and how it could form. So as usual I checked the internet's most reliable for definitions - google, Schlumberger's oilfield glossary, and Not getting anywhere, I decided to do some research and this is what I have come up with.

As the name suggests, these are rocks made from flakes and may have different compositions. They may be of dolostones/dolomites (flake-breccias) origin (Fairchild, 1980) or
they may be of mudstone (mud-flake breccias) origin (Fairchild, 1980, Pickering, 2005).

I have so far, mostly come up with them being formed in marine settings; be it shallow or deep, but that maybe because I am biased towards reading more about marine carbonates.

In the shallow marine, these flakes are usually related to dessication cracks where after forming the cracks these flakes can be found within those cracks that are more susceptible to erosion as they get transported to those 'depressions'. (See figure below)

Another creation of the flakes may be due to sliding or slumping of the material as found in the more deeper marine settings. And whence formed into a rock, it's called a flakestone.

Flakestone portion as part of a flake pocket of dolostone flakes (Adapted from Fairchild, 1980)

My initial idea was that these flakestones were similar to conglomerates. In a manner, they are a type of breccia more than conglomerate since they may form due to slides and slumps and are more pointy at both the edges.

I hope one day that I will come across a flakestone and thus be no longer confused!


Fairchild, I. J., 1980. Sedimentation and origin of a Late Precambrian 'Dolomite' from Scotland. Journal of Sedimentary Petrology, v. 50, n. 2, p. 0423-0446.

Pickering, K. T., Corregidor, J., 2005. Mass-Transport Complexes (MTCs) and Tectonic Control on Basin-Floor Submarine Fans, Middle Eocene, South Spanish Pyrenees. Journal of Sedimentary Research, v. 75, n. 5, p. 761-783.

1 comment:

  1. Thanks to Silver Fox of the Detachment blog, i finally took the plunge to look at the AGI definition for Flakestone: