The Lewis Cliff (84º17'S 161º05'E) area has proved to be one of the more prolific meteorite stranding sites in the Transantarctic Mountains and one of the most difficult ones to search. Because of the high density of terrestrial rocks on the ice surface, two thirds of what we refer to as the Lewis Cliff Ice Tongue was searched on foot over four field seasons (It is interesting to note that the density of meteorites on the Ice Tongue correlates well with the area of highest terrestrial rock density). Over 1870 meteorite specimens, with a wide variety of meteorite types, have been recovered from the icefields at Lewis Cliff.

Ice appears to flow off the polar plateau over the Lewis Cliff escarpment and into Walcott Névé. Some of this ice is funneled northward into the narrow channel of the Lewis Cliff Ice Tongue. LEW15-Figure 1(83 KB JPEG) is an enlarged portion of the U.S.G.S. Buckley Island 1:250000 map of the Walcott Névé area showing the Lewis Cliff area. About 2.5 kilometers at its widest and approximately 8 kilometers long, the Ice Tongue terminates against a vast expanse of undulating ice-cored moraines below Mt. Achernar. LEW15-Figure 2 - (56 KB JPEG) is an low altitude aerial view of the ice tongue from the west.

Approximately 30-35 square kilometers of ice is exposed in the Lewis Cliff area. LEW15-Figure 3 (43 KB JPEG) is a low resolution ASTER image of the Lewis Cliff and Walcott Névé area.

A topographic step with 75 meters relief divides the Ice Tongue into two sections which we refer to as the lower Ice Tongue and the upper Ice Tongue. A north-south longitudinal profile down the center of the Ice Tongue is shown in LEW15-Figure 4 (13 KB JPEG).

Meteorites were first discovered on the Lewis Cliff Ice Tongue during reconnaissance in the 1985-1986 field season. Several days were spent in initial reconnaissance and systematic searches. ANSMET expeditions returned in the 1986-1987, 1987-1988, and 1988-1989 summers to conduct detailed searches of the Lewis Cliff icefields. In the 1990-1991 season a short visit was made and meteorites recovered. The area was again visited for a short time during the 1993-94 field season. Another 61 specimens were recovered from a small area of Meteorite Moraine, 31 meteorites were collected from the Ice Tongue, and 2 from the South Lewis Cliff Icefield. The locations of 2 specimens collected during the 1987-88 season from a small ice patch at the southeast corner of the Lewis Cliff Area map, informally referred to as the Central Walcott Icefield, were determined by GPS. One additional specimen was also recovered from near by.  During the 1997-98 season the ANSMET team working at the nearby Queen Alexandra Range- Goodwin Nunataks area made a couple of  trips to the Lewis Cliff icefields.  The ice area at the head of the Walcott Névé we call the South Walcott Icefield is an extension of the Lewis Cliff icefields.  A total of 20 specimens were recovered.  An additional 8 meteorites were also recovered from the Lewis Cliff Ice Tongue and Meteorite Moraine.  The 1999-2000 ANSMET field team traversed the area and recovered two specimens from the South Lewis Cliff icefield area

The bulk of the meteorites recovered at Lewis Cliff were found on the Ice Tongue. However, one area of ice-cored moraine situated below a steep ice slope to the east of the Ice Tongue had abundant meteorite fragments intermixed with the terrestrial rocks. We refer to this area as Meteorite Moraine. To date, 264 meteorite fragments have been found within or immediately adjacent to the moraine and upwind of it. From the South Lewis Cliff Icefield, south and upstream of the Ice Tongue, 137 meteorite specimens were recovered. A scattering of meteorites was found on other smaller ice patches in the area. Additional descriptions of the Lewis Cliff area can be found in Cassidy et al. (1992) and Harvey (2003).

LEW15-Table 1 is a tabulation of the types of meteorites recovered from among the 1871 meteorite specimens from the Lewis Cliff icefields.

Except for the Meteorite Moraine specimens, nearly all of the meteorites found prior to the 1999-2000 season were surveyed using theodolite and EDM methods. Subsequently, GPS has been employed to determine the position. Most of the meteorites from Meteorite Moraine were located relative to a local grid which was tied to the survey network.

One meteorite, LEW 87016, actually consisted of two specimens found approximately 195 meters apart. The name LEW 87024 was originally given to the northerly, or downwind specimen. Subsequently the samples were paired and a common name, LEW 87016 was given. No weight data for each individual specimen was preserved. Therefore the name of the meteorite is duplicated as LEW 87016,0 and LEW 87016,0 as is shown in the meteorite listing and the database. The total mass of the combined specimens is 16.8 grams.

Acknowledgments; We thank ANSMET field party members William Cassidy, Peter Englert, Twyla Thomas, and Carl Thompson who conducted the initial reconnaissance searches and mapping in the 1985-1986 season; William Cassidy, Austin Marden, Louis Lindner, Keizo Yanai, Chris Koeberl, and John Schutt (1986-1987); William Cassidy, Joan Fitzpatrick, Robert Fudali, Ralph Harvey, John Schutt,and Faith Vilas (1987-1988); William Cassidy, David Blewett, Monica Grady, Randy Korotev, Scott Sandford, John Schutt, and Roberta Score (1988-1989); Mario Burger, William Cassidy, Ghislaine Crozoz, and Robert Walker (1990-1991); William Cassidy, Keith Echelmeyer, Candice Kohl, Thomas Meisel, and Sarah Russel, and John Schutt (1993-1994); Luann Becker, Gretchen Benedix, Marta Corbin, Doug Middlefeldt, John Schutt, Tim Swindle, Mark Wieczorek, and Karl Wirth (1997-1998); Phil Bland, Henning Haack. Kevin Righter, Peter Pesch, John Schutt, and Andreas Weigel (1999-2000). We appreciate the contribution to the 1990 meteorite collection by Gunter Faure and Eric Hagen. G. Parasso, E. Eckel, M. Hower, and G. Sandul of the U.S.G.S. established the primary survey control stations in 1985-1986.

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