Cores recovered sand from depths of roughly 2 miles on or near the Mid-Atlantic Ridge

William Maurice Ewing (1906–1974) stands as one of the most influential figures in 20th-century earth sciences. A Texas-born geophysicist and oceanographer, he led or directed more than 50 oceanic expeditions, transforming our understanding of the seafloor from a static, featureless plain into a dynamic, geologically active realm.

His work laid essential groundwork for plate tectonics, revolutionized marine geophysics, and established institutions and methods still used today.

Ewing combined rigorous physics with relentless fieldwork at sea. He developed or improved key instruments (echo sounders, piston corers, seismic arrays, deep-sea cameras, gravimeters, and towed magnetometers), collected vast datasets, and fostered collaborations that produced groundbreaking discoveries. His efforts shifted oceanography from sporadic, limited cruises to systematic, near-continuous global exploration.

Early Career and Pre-War Foundations

Born May 12, 1906, in Lockney, Texas, Ewing earned his B.A. (1926), M.A. (1927), and Ph.D. (1931) from Rice Institute (now Rice University). His doctoral work focused on seismic ray paths. He taught at Lehigh University and began applying explosive seismology to study the Earth’s crust.

In the mid-1930s, with support from geologists like Richard Field and William Bowie, Ewing secured ship time on the Woods Hole Oceanographic Institution’s research vessel RV Atlantis. He conducted pioneering seismic refraction surveys on the continental shelf off the U.S. East Coast. One early result: sediments up to 3,800 meters (12467 feet) thick off Virginia. He also worked with Harry Hess aboard the submarine USS Barracuda to trace gravity anomalies around the Puerto Rico Trench and Lesser Antilles.

These shallow-water experiments honed techniques for deeper work and highlighted the contrast between continental and oceanic crust.

World War II and the SOFAR Channel

During WWII (on leave from Lehigh, working at Woods Hole), Ewing’s team advanced underwater acoustics for the U.S. Navy. They discovered the SOFAR (Sound Fixing and Ranging) channel—a deep layer (roughly 700–1,300 meters (4265 feet)) where sound speed is minimized, allowing low-frequency sound to travel thousands of kilometers with little attenuation. This had major implications for submarine detection, long-range communication, and later SOSOS arrays. Ewing also developed the “sofar bomb” for precise sound ranging.

These wartime efforts refined instruments and built expertise that Ewing carried into peacetime oceanography.

The Landmark 1947 Atlantis Expedition to the Mid-Atlantic Ridge

After joining Columbia University in 1946 (full professor in 1947), Ewing secured two months aboard RV Atlantis in summer 1947 for his first major post-war expedition focused on the Mid-Atlantic Ridge. He outfitted the ship with echo sounders, towed hydrophones for seismic work, dredges, sediment corers, and underwater cameras.

Key findings included:

• Extensive mapping of ridge topography, revealing parallel ridges and troughs rather than a single massive feature.
• Discovery/recognition of flat abyssal plains (e.g., between Bermuda and the ridge), which were surprisingly level and covered by relatively young sediments.
• Dredged rocks (basalts and others) and seismic data indicating thin oceanic crust (around 5–6 km to the Mohorovičić discontinuity, or Moho, versus ~30+ km on continents).
• Early observations of a deep valley with steep slopes on the ridge flank, which Ewing interpreted as possibly a fault scarp and rift valley linked to earthquakes (later clarified as part of fracture zones or the axial rift system).

This cruise produced immediate results, including a 1948 National Geographic article by Ewing on “Exploring the Mid-Atlantic Ridge” and a 1949 paper with Ivan Tolstoy. It challenged views of a static ocean floor and hinted at dynamic processes. Bruce Heezen (recruited around this time) contributed background research but did not sail on this particular cruise.

Founding Lamont and the Era of Global Expeditions

In 1949, Ewing founded the Lamont Geological Observatory (now Lamont-Doherty Earth Observatory, LDEO) on the former Lamont estate in Palisades, New York. It became a hub for marine geophysics with labs, a massive core repository, and a focus on data collection.

Ewing prioritized dedicated ships for year-round operations rather than short, targeted cruises:

• RV Vema: A former schooner chartered and then purchased in the early 1950s. It logged over a million miles—the first research vessel to do so—circling the globe repeatedly and collecting continuous profiles of bathymetry, gravity, magnetism, and seismic data, plus hundreds of sediment cores (“a core a day” in some periods).
• RV Robert D. Conrad (acquired 1962): Another high-mileage vessel that also exceeded one million miles.

These ships operated relentlessly (often 300+ days/year), amassing unprecedented datasets across all oceans. Ewing’s philosophy emphasized quantity and breadth of observations alongside targeted experiments.

Major Discoveries with Colleagues

Ewing collaborated with exceptional talents, including Bruce Heezen, cartographer Marie Tharp, and sedimentologist David Ericson.

• Mid-Atlantic Ridge and Global Ridge System: Building on 1947 work and new profiles, Tharp identified a central rift valley in Atlantic crossings around 1952–1953. Heezen and Ewing linked it to earthquake epicenters. By the late 1950s, they showed the ridge system extended ~40,000 miles (64373 kilometers) (65,000 km) worldwide—Earth’s largest geological feature—encircling the globe like seams on a baseball.
• Turbidity Currents: Cores and cable-break data (e.g., 1929 Grand Banks earthquake) confirmed powerful underwater sediment avalanches that carve canyons, transport material to abyssal plains, and explain disrupted layering.
• Oceanic Crust and Moho: Seismic refraction showed consistently thin crust (~5 km) beneath oceans.
• Sediment Cores and Paleoceanography: Thousands of cores revealed recent sediments on old seafloor, magnetic reversals (aiding dating and spreading confirmation), and climate records.
• Magnetic Anomalies: Towed magnetometer surveys produced striped patterns later key to seafloor spreading.
• Other: Abyssal plains formation, submarine canyons, heat flow, and more.

Ewing was initially cautious about continental drift but his data (and that of colleagues) proved crucial for Harry Hess’s seafloor spreading hypothesis and the plate tectonics revolution of the 1960s. Lamont data helped confirm it by the mid-to-late 1960s.

Instruments, Techniques, and Broader Impact

Ewing’s team improved or invented tools like the piston corer (for longer, less-disturbed cores), precision depth recorders, air guns/sparkers (safer seismic sources), and deep-sea photography. They advanced continuous underway measurements and integrated multiple data types (bathymetry + seismic + gravity + magnetism + cores).

Ewing published over 300–340 papers, led Lamont until 1972, served as chief scientist on Glomar Challenger (Deep Sea Drilling Project), and received major honors including the National Medal of Science (1973) and posthumous Penrose Medal. A research vessel (RV Maurice Ewing) and medals were named after him.

Connection to Atlantis

Cores recovered sand from depths of roughly 2 miles (3.22 kilometers) on or near the Mid-Atlantic Ridge

The 1948 National Geographic Article (Primary Source)In his article “Exploring the Mid-Atlantic Ridge” (National Geographic Magazine, Vol. 94, No. 3, September 1948, pp. 275–294), Ewing described results from the 1947 expedition (sometimes called Atlantis Cruise 150). He detailed bathymetry, seismic data, dredged rocks, and sediment cores from the ridge area. A key detail repeatedly highlighted in Atlantis discussions: cores recovered sand resembling beach sand (coarse, clean sand like that found in coastal or littoral environments) from depths of roughly 2 miles (3.22 kilometers) (about 3,000+ meters) on or near the Mid-Atlantic Ridge, including areas associated with the Azores region or its extensions. Ewing noted the puzzle of how such sand ended up there, in the context of flat abyssal plains and other features suggesting dynamic geological processes.

This article is the main primary source where Ewing directly discusses these sediment findings. Atlantis proponents (e.g., in online discussions, books, and videos referencing Randall Carlson or similar researchers) interpret the “beach sand” at depth as evidence that parts of the ridge or nearby areas were once above sea level or near coastlines relatively recently (e.g., post-Ice Age or ~20,000 years ago in some claims), potentially linking it to Plato’s description of a sunken island.

Ewing himself presented it strictly as a geological observation without referencing Atlantis, Plato, or any lost civilization.

The Floors of the Oceans

In the collaborative monograph The Floors of the Oceans, I. The North Atlantic (Bruce C. Heezen, Marie Tharp, and W. Maurice Ewing, Geological Society of America, 1959), the authors map and describe seafloor features. It includes a reference to the “Atlantis-Plato-Cruiser-Great Meteor Seamount Chain” south of the Azores.

This refers to actual named geological features (seamounts/guyots) in that region:

• There are real seamounts named Atlantis Seamount, Plato Seamount, Cruiser Seamount, etc., part of a chain extending from the Azores area toward the Great Meteor Seamount.
• These names likely come from exploratory ships (like RV Atlantis) or conventional naming practices, with “Plato” possibly nodding to the philosopher in a light or coincidental way.