Texas Navy Friends and Colleagues:
The field work for the Invincible magnetometer survey was completed on Saturday afternoon, November 10, by Bob Gearhart and his assistant, Ed Baxter. The raw data is in the box. They covered the entire area initially on Thursday and Friday, November 8 and 9, and after reviewing the data plot, used Saturday to run additional tracks where any data was missing, and then get additional data on some selected targets that seemed significant.
There are numerous anomalies across the 23-acre site. There are a few large anomalies that might be looked at using probing or sampling at some point in the future. There was nothing that immediately jumped out at Gearhart as obviously a shipwreck, but we do now have concrete data to work with. These are very preliminary findings, and will be refined later in his analysis and report, which will take several weeks more to complete. Gearhart has a database of 30 or so known wrecks that he’s studied before, and can compare this new data with that, to get a better sense of what we might be looking at.
Can we claim to have found Invincible? No. Can we be sure these anomalies are the remains of a vessel? Again, no. But this is a starting point for further study.
This project was done under a Phase I Survey permit issued to Gearhart by the Archaeology Division of the Texas Historical Commission, and reviewed and approved by representatives of the Galveston Parks Board and the City of Galveston.
Gearhart is owner and principal of BOB Hydrographics, that specializes in hydrographic surveys supporting infrastructure and environmental projects on coastal and inland waters. Prior to establishing BOB Hydrographics, he served as hydrographer and marine archaeologist with several firms, notably with PBS&J, Inc. (1998-2010) and Espy, Huston & Associates (1984-92), that did extensive work surveying, recording, and analyzing shipwrecks in Texas coastal waters. Gearhart holds a BA in Anthropology from Iowa State University, and an MA in Anthropology from the University of Missouri – Columbia.
Gearhart led the archaeological team that recovered the remains of the Civil War gunboat USS Westfield, that was blown up at the end of the Battle of Galveston in 1863, and was long thought to have been lost. Of particular relevance to his role on the Invincible Project, he authored the chapter, “Archaeological Interpretation of Marine Magnetic Data” for the The Oxford Handbook of Maritime Archaeology, published by Oxford University Press in 2014.
A magnetometer is a passive system that detects fluctuations, or anomalies, in the earth’s background magnetic field caused by ferrous metal, typically iron or steel. The readings can’t give absolute values on the amount of metal, or create a visualization of what those sources look like. (I.e., an iron cannon wouldn’t look like a cannon on the plot; it would look like a strong blurp in the normal, background magnetic field.) Importantly, this data also can’t reliably indicate the depth of the objects causing the anomaly. We don’t know what is at this location, but there is something (or perhaps some things) there. Once we receive Gearhart’s final, technical report, we can start looking at the best ways to carry this work forward to the next step, that may be additional remote-sensing testing, sampling by probing or coring, or a combination of those things.
The search for Invincible has been a long-standing project for the TNA, going back to the 1980s. It’s involved lots of players over the years, including Clive Cussler’s National Underwater and Marine Agency (NUMA). Many folks in the TNA have contributed time, effort, and funding to those efforts, and we appreciate their dedication to the project. The goal of finding Invincible has been kept current by many folks in the TNA, most recently by Adm. Will Fisher. It’s been a long journey, and we hope that this survey will mark the beginning of a new and exciting phase of it.
In particular, it’s taken a lot of work over the last eighteen months to bring the TNA to this point. I would like to extend my sincere thanks to several critical players in this process. Admirals Dick Hatch and Jerry Patterson, TNA President and Past President respectively, were unfailing in their support and encouragement. TNA Past President Adm. Bill Turner tackled the critical (and unenviable) task of fund-raising for the project, and Adm. Jeff Corbin and the Tom Toby Squadron organized a raffle for Warbird rides to raise money for the project. Adm. Tom Oertling developed the archival chart research that suggested this search area as a likely target for investigation. There were many others, besides, who contributed in ways large and small to bring us to this point.
Major Plank Owner donors to this project to date include:
Adm. Jeremy and Shana Jones, Houston
Adm. Bob Wright, Shoreacres
Adm. Brantly Minor, Houston
Adm. Ed and Marsha Bluestein, Houston
David and Gloria Walker, Bolivar
Adm. By Baldridge, Seabrook
Adm. Dave and Mary Haglund, Houston
Anonymous, Gonzales
Adm. Rick M. Dempsey, Dallas
Adm. Herb Hammond, Dallas
Adm. Glenn Seureau, Houston
Adm. Tom and Suzanne Hauser, San Marcos
Adm. Candice Zummo and Adm. Butch Spafford, Groves
Adm. Richard and Carol Ann Weitzel, San Antonio
Adm. Chester F. Barnes, III, Lake Jackson
Adm. Jim and Jo Tyson, Katy
Skip Harrison, Kemah
Search for the Invincible Committee Members for 2019 include:
Adm. Chester Barnes
Adm. Jeff Corbin
Adm. Dave Haglund
Adm. Andy Hall (Interim Chairman)
Adm. Paula Morris
Adm. Tom Oertling
Adm. Butch Spafford
Adm. Bill Turner
_____
Adm. Andy Hall
Interim Chairman, Search for the Invincible Committee
Operations Officer/Historian, Charles E. Hawkins Squadron
Thanks Andy. I have it in the newsletter…any photos?
On Fri, Nov 16, 2018 at 11:28 AM Charles E. Hawkins Squadron wrote:
> Andy Hall posted: ” Texas Navy Friends and Colleagues: The field work for > the Invincible magnetometer survey was completed on Saturday afternoon, > November 10, by Bob Gearhart and his assistant, Ed Baxter. The raw data is > in the box. They covered the entire area init” >
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Pictures sent by e-mail. Weather was lousy for pictures.
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