Pebbles in the Lower Colorado River, Texas a Study in Particle Morphogenesis

  title={Pebbles in the Lower Colorado River, Texas a Study in Particle Morphogenesis},
  author={Edmund D. Sneed and Robert L. Folk},
  journal={The Journal of Geology},
  pages={114 - 150}
The Colorado River in its course from central Texas to the Gulf of Mexico carries quartz, chert, and limestone pebbles which can be traced for distances of up to 270 miles from their source. Limestone is so soft that it reaches its limiting roundness in the first few miles and thereafter undergoes no further increase. Harder quartz rounds much more slowly but eventually attains the same high limiting roundness value as limestone. Chert, being brittle, tends to spall and only rounds slightly… 

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