Udden, Johan August

About the author

Johan August Udden, born in 1859 in Sweden, later became a key figure in American geology after moving to the U.S. His work revolved around sedimentology, focusing on the classification of sediments based on particle size.

His publication Fossil Ice Crystals: An Instance of the Practical Value of 'Pure Science' is a landmark study where he demonstrated how past climatic conditions could be inferred from geological records, specifically through the study of fossil ice crystals.

Udden's legacy in geology includes the Udden-Wentworth scale, which has standardized sediment size classification, influencing geological research and education for over a century.