Annotated record of the detailed examination of Mn deposits from R/V Atlantis - Cruise 151 (Dec. 1947) in the Atlantic Ocean

One of the objectives of WHOI Atlantis Cruise 151, covering the period from 7 December 1947 to 18 June 1948, was to obtain as complete a sampling of the sea bottom of the Meditterranean and Aegean Seas as was compatible with the remainder of the scientific program. It was furthermore planned to make concurrent bottom photographs as a means for studying the correlation between bottom sediments and the morphology of the sea floor. The photographs also held the possibility of determining the presence of bottom fauna. The underwater camera used for this work was loaned to us by Dr. Maurice Ewing of Columbia University. As it was fitted with a one foot long coring tube at the base of its pole a majority of the bottom samples were obtained by the camera itself. On the way to Gibraltar, several bottom photos were taken in the Atlantic ocean. One of them was the deepest underwater photograph ever taken at the tima (3026 fathoms) showing a cluster of objects, some as much as 5 inches across on a clay bottom. These appeared to be manganese nodules, judging from their rounded and bulbous shape, especially the potato-like form of some of them. A core sample obtained at the same spot with a corer attached to the camera stand contained abundant manganese grains.

(Table 1) Results from XRD analysis as well as sediment type and selected results from ring shear experiments

The location of the seaward tip of a subduction thrust controls material transfer at convergent plate margins, and hence global mass balances. At approximately half of those margins, the material of the subducting plate is completely underthrust so that no accretion or even subduction erosion takes place. Along the remaining margins, material is scraped off the subducting plate and added to the upper plate by frontal accretion. We here examine the physical properties of subducting sediments off Costa Rica and Nankai, type examples for an erosional and an accretionary margin, to investigate which parameters control the level where the frontal thrust cuts into the incoming sediment pile. A series of rotary-shear experiments to measure the frictional strength of the various lithologies entering the two subduction zones were carried out. Results include the following findings: (1) At Costa Rica, clay-rich strata at the top of the incoming succession have the lowest strength (µres = 0.19) while underlying calcareous ooze, chalk and diatomite are strong (up to µres = 0.43; µpeak = 0.56). Hence the entire sediment package is underthrust. (2) Off Japan, clay-rich deposits within the lower Shikoku Basin inventory are weakest (µres = 0.13-0.19) and favour the frontal proto-thrust to migrate into one particular horizon between sandy, competent turbidites below and ash-bearing mud above. (3) Taking in situ data and earlier geotechnical testing into account, it is suggested that mineralogical composition rather than pore-pressure defines the position of the frontal thrust, which locates in the weakest, clay mineral-rich (up to 85 wt.%) materials. (4) Smectite, the dominant clay mineral phase at either margin, shows rate strengthening and stable sliding in the frontal 50 km of the subduction thrust (0.0001-0.1 mm/s, 0.5-25 MPa effective normal stress). (5) Progressive illitization of smectite cannot explain seismogenesis, because illite-rich samples also show velocity strengthening at the conditions tested.

Wahoo Base Ball Club of Dexter, Mich vs. Ann Arbor BB Club

On verso: Back row, left to right: 1. Irving Keal R.F. 2. Geo. Hostler C. 3. Ed Appleton 3B 4. Geo. Smith 2B 5. Byron Tyler 1st B 6. Geo. Presley CF 7. Eugene Beal SS 8. Henry Ewing P 9. Ed Hoyt LF. Matted oval 7x5 1/4 photoprint.

Latin-American universities and special schools /

Includes index.

Utilization of the waters of Mojave River, California /

"A contribution from Bureau of Agricultural Engineering."

Effects of thermal treatment of sludge on municipal wastewater treatment costs /

Mode of access: Internet.

Dynamic response of human and primate head and neck to +Gy impact acceleration. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

The Indian manual of hygiene : being King's Madras manual of hygiene /

Title on cover: Salus populi suprema lex.

Synthetic detergents in soils and ground waters /

"January, 1961."

Fate of synthetic detergents in soil and ground water /

"November, 1965."

Recovery of uranium from saline solutions by biological slimes : final report /

"October 1, 1955."

Poultry nutrition, for the use of feed manufacturers, feed dealers, feed salesmen and service men, veterinarians, hatcherymen, breeders, and poultrymen. A text and reference book for instructors, students, and all persons interested in poultry feeds and feeding.

First ed. published in 1941 under title: Handbook of poultry nutrition.

From Gallipoli to Baghdad,

Mode of access: Internet.

Reports of the secretary of the Treasury of the United States,

Reports for 1801-1828 were also reprinted in 2 vols. with the reports of Alexander Hamilton on public credit, on a national bank, on manufactures, and on the establishment of a mint, prefixed. Washington, Printed by D. Green, 1828-29.