Thomas C. Hanks

{{Short description|American seismologist}} {{About|the seismologist|the actor|Tom Hanks}} {{Use mdy dates|date=May 2026}} {{Use American English|date=May 2026}}

{{Infobox scientist | name = Thomas C. Hanks | birth_name = Thomas Colgrove Hanks | image = | caption = | birth_date = {{Birth date|1944|11|29|mf=y}} | birth_place = Washington, DC, U.S. | death_date = {{Death date and age|2024|3|5|1944|11|29|mf=y}} | death_place = Palo Alto, California, U.S. | residence = | citizenship = | nationality = | ethnicity = | field = Seismology | alma_mater = Princeton<br />California Institute of Technology | work_institutions = | doctoral_advisor = | doctoral_students = | known_for = Moment magnitude scale | author_abbrev_bot = | author_abbrev_zoo = | influences = | influenced = | prizes = | religion = | footnotes = | signature = }}

'''Thomas Colgrove Hanks''' (November 29, 1944 – March 5, 2024) was an American seismologist. He worked for the US Geological Survey (USGS) in Menlo Park, California. Dr. Hanks was a member of the Seismological Society of America, the American Geophysical Union, the Earthquake Engineering Research Institute, the Geological Society of America, the Peninsula Geological Society at Stanford, and many related geological societies. Dr. Hanks authored dozens of scholarly papers in strong-motion seismology and tectonic geomorphology.

Hanks was born in Washington DC, the middle of three sons.<ref>{{cite book |editor-last1= |editor-first1= |date=1966 |title=The Nassau Herald: A Record of the Class of Nineteen Hundred and Sixty-Six |location=Princeton, NJ |publisher=Princeton University |page=151 |url=https://dpul.princeton.edu/catalog/dcdj52wj880 |access-date=May 14, 2026}}</ref> Hanks graduated with a B.S.E. in geological engineering from Princeton University in 1966 after completing a senior thesis titled "The meaning of a heat flow experiment on Mars."<ref>{{Cite book|last=Hanks|first=Thomas C.|url=https://catalog.princeton.edu/catalog/8239565|title=The meaning of a heat flow experiment on Mars|date=1966|publisher=Princeton, NJ: Princeton University, Department of Geological Engineering|language=English}}</ref> He later received his PhD from the California Institute of Technology in 1972 after completing a dissertation titled "A Contribution to the Determination and Interpretation of Seismic Source Parameters".<ref>{{cite web |last1=Hanks |first1=Thomas C. |title=A Contribution to the Determination and Interpretation of Seismic Source Parameters |url=https://thesis.library.caltech.edu/6624/1/Hanks_tc_1972.pdf |website=caltech.edu |access-date=22 March 2022}}</ref>

In 1979 the Japanese-American seismologist Hiroo Kanamori, professor of seismology at the California Institute of Technology and Dr. Hanks suggested the use of moment magnitude scale to replace the Richter magnitude scale for measuring the relative strength of earthquakes. The reason was that the Richter scale saturates at magnitudes greater than about 5.5, while the Moment magnitude scale does not saturate.<ref>[http://www.geolsoc.org.uk/gsl/geoscientist/page708.html The Geological Society – "Off the Scale!" editorial by Ted Nield in Geoscientist 17.6 (June 2007)] {{webarchive|url=https://web.archive.org/web/20071009115234/http://www.geolsoc.org.uk/gsl/geoscientist/page708.html |date=2007-10-09 }}</ref>

On March 5, 2024, Dr Hanks died from a stroke after battling prostate cancer.<ref>{{Cite web |title=Thomas C. Hanks ’66 {{!}} Princeton Alumni Weekly |url=https://paw.princeton.edu/memorial/thomas-c-hanks-66 |access-date=2025-12-27 |website=paw.princeton.edu |language=en}}</ref><ref>{{Cite web |title=Princeton Class of 1966 |url=https://tiger1966.org/page/Memorials/Memorials_2024/2024_03_05_ThomasCHanks |access-date=2025-12-27 |website=tiger1966.org}}</ref> A scientific symposium celebrating his life was held by the USGS at the Ames NASA Research Center in October 2024.<ref>{{Cite web |last=USGS |title=Earthquake Science Center |url=https://earthquake.usgs.gov/esc/symposium/ |access-date=2025-12-27 |website=earthquake.usgs.gov |language=en}}</ref>

==References== {{Reflist}}

==Further reading== * {{cite journal | last=Minson | first=Sarah E. | last2=Baltay | first2=Annemarie S. | last3=Cochran | first3=Elizabeth S. | last4=Nevitt | first4=Johanna M. | last5=Hickman | first5=Stephen H. | last6=Thatcher | first6=Wayne R. | last7=Baker | first7=Jack W. | last8=Diggles | first8=Michael F. | title=Tom Hanks—A Remembrance | journal=Seismological Research Letters | volume=96 | issue=1 | date=2025 | issn=0895-0695 | doi=10.1785/0220240332 | pages=7–8}}

==External links== *[https://www.princeton.edu/paw/web_exclusives/alumni_spotlight/as_012506hanks.html "Quake Watcher" Princeton Alumni News profile on Hanks]

{{DEFAULTSORT:Hanks, Thomas C.}} Category:American seismologists Category:Fellows of the Seismological Society of America Category:Princeton University School of Engineering and Applied Science alumni Category:Year of birth missing (living people) Category:1944 births Category:2024 deaths Category:California Institute of Technology alumni