In clastic sediments, the correct order of decreasing grain size is
Show Hint
- Boulder > pebble > silt > sand
- Granule > pebble > clay > silt
- Cobble > granule > silt > clay
- Granule > pebble > sand > silt
The Correct Option is C
Solution and Explanation
Step 1: Evaluating each option:
(A) Boulder > pebble > silt > sand: Incorrect order: sand is coarser than silt
(B) Granule > pebble > clay > silt: Incorrect: pebble is larger than granule. Silt is coarser than clay
(C) Cobble > granule > silt > clay: Cobble (64-256 mm) > Granule (2-4 mm) > Silt (0.0039-0.0625 mm) > Clay (<0.0039 mm). This is the correct decreasing order
(D) Granule > pebble > sand > silt: Incorrect: pebble is larger than granule
Answer: (C) Cobble > granule > silt > clay
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