Submarine Mountain Named for William Laurence Dowd

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Submarine mountain named for William Laurence Dowd June 25, 1965 A major submarine mountain discovered in the Eastern Pacific Ocean by scientists from the Scripps Institution of Oceanography has been named by the scientists in honor of William Laurence Dowd, a Scripps graduate student who was found slain in his apartment June 6. The seamount, to be known as Dowd Guyot, is located about 1,000 miles south of San Diego and about 1,000 miles west of Mexico. It was discovered June 22 by scientists aboard the Scripps research ship Argo operating on a student cruise for the Department of Earth Sciences under the direction of Dr. Manuel N. Bass, Assistant Professor of Geology. Dowd, a brilliant graduate student in the field of geochemistry research, took part in a similar cruise last year and had, in fact, sailed just east of the region where the seamount was discovered. The current student cruise, which left San Diego June 17, marks the first time Argo has put out to sea since the tragedy occurred. According to Dr. Henry W. Menard, Professor of Geology, who received word of the discovery by radio from Dr. Bass, the mountain is a flat topped seamount, or guyot, which probably was an island thousands of years ago. Its top is four miles in diameter and from 280 to 290 fathoms beneath the surface of the ocean. It has a narrow central pinnacle, the top of which is 257 fathoms beneath the surface. The base of the seamount is about 19 miles in diameter at a depth of 2,250 fathoms giving the mountain a height of about 12,000 feet or nearly two nautical miles. If there were no water, the guyot would look much like Mount Rainier does from Seattle, Washington. Dr. Menard said the seamount is an important peak scientifically since it probably was an island at one time. He said the Eastern Pacific Ocean is known to be the largest body of open water without sunken islands. To find an isolated island is rare because seamounts usually occur in groups. He said the Dowd Guyot is the only ancient island known to exist within 500 miles. If the guyot was at one time an island, it will prove immensely important to oceanographers studying animal migration and plant development in the Pacific Ocean area. Dr. Menard said that such islands were used as stepping stones by animals preferring shallow water and also as lodgement for plants. By dredging the flat top of the seamount, the scientists should be able to recover evidence of plant and animal life that flourished before the island sank some 1,600 feet below the ocean surface. Dr. Menard said the seamount may also be valuable to fishermen in the Eastern Pacific. Tuna prefer shallow banks, especially where few ships have travelled. He said the last seamount discovered in this region, the Shimada Guyot, produced some 10 percent of the national tuna catch within the first year of discovery..

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Appendix 2. the Mystery of Guyot Formation and Sinking
Appendix 2 The Mystery of Guyot Formation and Sinking Origin of Guyots Unknown In 1946, geologist Harry Hess was the first geologist to describe guyots (flat-topped seamount).1 Since then, the number of guyots has become numerous. Resolution Guyot in the Mid-Pacific Mountains that was studied in the 1990s by the Deep Sea Drilling Project2 is a typical guyot. Figure A2.1 shows the silhouette. Ever since Hess’s time, the cause of the flat top has eluded explanation.3 Winterer and Met- Figure A2.1. Silhouette of Resolution Guyot zler maintain: “Since Hess first recognized them in the Mid-Pacific Mountains (drawn by Mrs. Melanie Richard). in 1946, the origin of flat-topped seamounts, or guyots, has remained one of the most persistent problems in marine geology.”4 Since guyots are believed to have been truncated near sea level, there are two suggested subsid- ence mechanisms used to explain why they are now found well below sea level. But some guyots must have become flat well below sea level. Not All Guyots Eroded At Sea Level Many scientists have simply assumed that the flat top of a guyot was eroded at or near sea level.5,6 ‘This has been challenged by a few marine geologists.’7,8 For instance, a number of guyots near the East Pacific Rise have been attributed to the infilling of calderas by small lava flows well below sea level.9,10,11,12 “But, these guyots are small 1 Hess, H.H., 1946. Drowned ancient islands of the Pacific Basin. American Journal of Science 244:772–791.
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