He worked with Professors Alec Skempton and Alan W. Bishop and obtained his PhD degree in 1958; his thesis title was "The seismic stability of earth dams".

Moreover, Harry Bolton Seed, the founding father of the diverse academic field geotechnical earthquake engineering, in the 19th Rankine Lecture[10] acknowledged the influence of Ambraseys, "... who introduced him to the problems of earthquakes and encouraged him to become involved in this new area pointing out the enormous field laboratory that existed in California..." Ambraseys' early work [11][12][13] on the seismic stability of earth dams set the foundations of a new method of analysis which was later further developed by other researchers, the "shear beam" method; which was an early attempt to consider the dynamic behavior of an earth dam due to seismic wave propagation.

He personally searched, found and collected an enormous amount of information about earthquakes which existed in various libraries, manuscripts and other forms of written communication around the world.

"His ability to speak fluently a number of languages allowed his direct involvement in the search for the original sources of earthquake information.

In addition to his research activities, he established a strong academic training at Imperial College, with relevant modules both in the undergraduate and postgraduate curriculums.

[31] This medal is the highest honor granted by the SSA and it is awarded no more than once a year for outstanding contributions in seismology and earthquake engineering.

[1] Only five living persons received this rare distinction: (in alphabetical order) Nicholas Ambraseys, Ray W. Clough, George W. Housner, Thomas Paulay and Joseph Penzien.

In 2014, the Department of Civil Engineering at Imperial College, SECED[33] and the British Geotechnical Association (BGA)[34] organised a pre-Rankine seminar (an annual half-day seminar held at Imperial College before the prestigious Rankine Lecture) to honour and commemorate Professor Ambraseys's great contribution to the field of Earthquake Engineering, called "Nicholas Ambraseys Memorial Symposium".

[37] An obituary written by two of Professor Ambraseys's former students (John Douglas and Sarada K. Sarma) was published in the soil mechanics journal Geotechnique in 2013.