1920 AD–2006 AD
Marie Tharp
Oceans, navigation & cartography · Hydrography & bathymetry · Oceanography
An American geologist and cartographer, Tharp transformed echo-sounding profiles and seismic data into coherent maps of submarine relief with Bruce Heezen. By identifying the Mid-Atlantic Ridge rift valley, she made evidence for seafloor spreading visible despite barriers that initially kept her from going to sea.
Precision, calendar, and review
- Start
- year · no uncertainty qualifier in this record
- End
- year · no uncertainty qualifier in this record
- Calendar and convention
- Historical-era years; the source calendar is not identified. No conversion of days is assumed.
- Year zero
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- Documentary review
- Date not recorded
Reading the date: life span.
Sources
- 1. lamont.columbia.edu (opens in a new tab)
Source provenance and scope
- Publication date
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- 2026-09-23
The correspondence between this reference and individual claims has not yet been itemized.
- 2. www.lib.uchicago.edu (opens in a new tab)
Source provenance and scope
- Publication date
- Pending verification: the source could not be accessed
- Bibliographic date checked
- 2026-09-23
The correspondence between this reference and individual claims has not yet been itemized.
This record is an editorial synthesis. Consult the sources to check claims and their limits. Chronological relationships alone do not establish causation.