Current Abstract

May 19th, 2026 Meeting Abstract

This Month’s Topic: The Life and Legacy of Thomas W. Dibblee

Presented by: Jonathan Hoffman, Ph.D. & Susie Bartz

Abstract: 

Thomas W. Dibblee, Jr. (1911-2004) was an incomparable field geologist with a
mapping career that spanned 7 decades and covered over a quarter of California
(>40,000 square miles). A suite of innate skills aided Dibblee’s remarkable work,
including an uncanny memory and recognition of visual patterns, an excellent eye for
judging angles, and an inexhaustible ability to traverse harsh terrain. Tom mapped for
oil companies and spent 25 years with the United States Geological Survey, making
numerous notable contributions to geologic research, including the proposal of more
than 350 miles of right-lateral displacement along the San Andreas Fault Zone.
Dibblee continued to map after his retirement in 1977, and in 1986, friends and
colleagues formed the Dibblee Geological Foundation with the mission of preserving the
scientific, technical, educational, and economic value of Tom’s life work. Maps were
updated by Dibblee and colleagues and provided standardized colors and formats. In
total, 419 updated “Dibblee Maps” were published and have informed and benefitted
numerous California industries, including mining, energy development, engineering and
land development, environmental consulting, and insurance. Today, the Dibblee
Geology Center at the Santa Barbara Museum of Natural History is dedicated to
Dibblee’s ideals of advancing knowledge of the Earth through research, providing expert
geologic advice to both public and private interests, and advancing public education in
geology.

Biography: