give us an understanding of the breadth of
LITERATURE CITED
materials present in the solar system in this size
range.
ASCE (1975) Sedimentation Engineering. ASCE
Our collector worked well despite the severe
Manuals and Reports on Engineering Practice No.
well topography. We learned that a 2.5-m collec-
54. New York: American Society of Civil Engineers.
tor is too long and is not needed for the condi-
Blanchard, M.B., D.E. Brownlee, T.E. Bunch, P.W.
tions we encountered; that available motor torque
Hodge, and F.T. Kyte (1978) Meteor Ablation
(rather than traction) limited the collector's mo-
Spheres from Deep-Sea Sediments, NASA Tech-
bility over the well bottom; and that visual feed-
nical Memorandum 78510.
back is essential to negotiate the well's complex
Bradley, J.P., S.A. Sandford, and R.M. Walker
topography (our camera lacked the ability to track
(1989) Interplanetary Dust Particles, in Meteorites and
the collector more than 5 m away from the cen-
the Early Solar System (Kerridge and Matthews,
ter). We hope to install more powerful motors and
Ed.). Tucson, Arizona: University of Arizona Press.
a pan/tilt camera to overcome these problems and
Brownlee, D.E. (1979) Meteorite mining on the
thus to increase the collection area and opera-
ocean floor (abstract). Lunar Planet. Science, 10:
tional efficiency. However, the more severe topog-
157158.
raphy away from the center of the well dictates
Brownlee, D.E. (1981) Extraterrestrial compo-
the need for a second, smaller, and more agile
nents. In The Sea 7 (C. Emiliani, Ed.). New York: J.
collector.
Wiley and Sons, Inc., p. 733762.
The complex bottom topography in the SPWW
Brownlee, D.E., D.A. Tomandl, and E. Olszewski
precluded our suctioning the entire bottom. We
(1977) Interplanetary dust; a new source of extra-
suctioned a gently curved, central plateau (about
terrestrial material for laboratory studies. In Pro-
18 m2) and three surrounding pockets (about 12
ceedings of the 8th Lunar and Planetary Science Con-
m2 total) and should be able to return to these ar-
ference, Houston, Texas, p. 149160.
eas annually to determine flux rates. From the five
Brownlee, D.E., D.J. Joswiak, S.G. Love, A.O.
collections, we retrieved approximately 200 g of
Nier, D.J. Schlutter, and J.P. Bradley (1993) Iden-
material. Microscopic examination of the 250 to
tification of cometary and asteroidal particles in
425-m size fraction from two of the five collec-
stratospheric IDP collections (abstract). In
tions suggests that one of every 1000 particles in
Proceeings of the 24th Lunar and Planetary Science
this size fraction is a melted micrometeorite. Not
Conference. Houston: Lunar and Planetary Insti-
counted are the unmelted micrometeorites present.
tute, p. 205206.
We think the flux value for the plateau of 6 107
Clark, E.F. (1965) Camp Century--Evolution of
g m2 yr1 is a minimum. The circlation velocities
concept and history of design, construction and
seem too low to add particles to the plateau, and
performance. USA Cold Regions Research and
we did not include unmelted particles in this esti-
Engineering Laboratory, Technical Report 174.
mate. With unmelted micrometeorites included,
Czajkowski, J., P. Englert, Z.A. Bosellini, and J.G.
the flux rate we calculate for the SPWW will be
Ogg (1983) Cobalt enriched hardgrounds--New
higher than that found by Maurette et al. (1987) in
sources of ancient extraterrestrial materials. Mete-
Greenland.
oritics, 18: 286287.
The particles retrieved will be analyzed and
Fredriksson, K., and R. Gowdy (1963) Meteoritic
compared with other cosmic dust collections to de-
debris from the Southern California desert.
termine differences in composition and weather-
Geochimica et Cosmochimica Acta, 27: 241243.
ing patterns. Because of the large number of par-
Ganapathy, R., D.E. Brownlee, and P.W. Hodge
ticles recovered, it is likely that very large IDP-
(1978) Silicate spherules from deep sea sediments:
like micrometeorites, extremely rare in other col-
Confirmation of extraterrestrial origin. Science, 201:
lections, will be found. In addition, identification
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of the terrestrial components (pollen, diatoms, ash,
Hagen, E.H. (1988) Geochemical studies of Neo-
etc.) from these samples would allow a statistically
gene till in the Transantarctic Mountains: Evidence
significant study of circum-Antarctic wind circu-
for an extraterrestrial component. M.S. thesis, The
lation during these time periods.
Ohio State University.
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