Weathering potential index for rocks based on density and porosity measurements

  • R. Pratap Singh
  • Vijay Kumar Upadhyay
  • Asok Das


Rock samples belonging to ten lithological types under different stages of weathering, were collected from different stratigraphical horizons at Bhagalpur. Their densities and porosities were determined experimentally and the data obtained were fitted empirically in a linear equation for each lithological type. The slopes of the curves, which were negative in each case, showed that the increase in porosity for the same decrease in density were in the order, white sandstone > ferruginous sandstone > white claystone > porphyritic gneiss > quartzite > pegmatite > amphibolite ≅ biotite gnejss > basalt ≅ dolerite. A new weathering potential index based on the density-porosity data was proposed and the values for a specific stage of weathering for all the lithological types studied fall within the same range.


Weathering classification weathering potential index rock density rock porosity 


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Copyright information

© Indian Academy of Sciences 1987

Authors and Affiliations

  • R. Pratap Singh
    • 1
  • Vijay Kumar Upadhyay
    • 1
  • Asok Das
    • 1
  1. 1.Bhagalpur College of EngineeringBhagalpurIndia

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