In 1879 Oldham became an assistant-superintendent with the Geological Survey of India , working in the Himalayas . He wrote about 40 publications for the Survey on geological subjects including hot springs , the geology of the Son Valley and the structure of the Himalayas and the Ganges plain . His most famous work was in seismology . His report on the 1897 Assam earthquake went far beyond reports of previous earthquakes . It included a description of the Chedrang fault , with uplift up to 35 feet and reported accelerations of the ground that had exceeded the Earth 's gravitational acceleration . His most important contribution to seismology was the first clear identification of the separate arrivals of P-waves , S-waves and surface waves on seismograms . Since these observations agreed with theory for elastic waves , they showed that the Earth could be treated as elastic in studies of seismic waves
1897 Assam earthquake
1897 Assam earthquake
Richard Dixon Oldham