Deep Core Drilling in the Ross Ice Shelf, Little America V, Antarctica

Drilling operations and core and drill hole investigations at Little America V in Oct. - Dec. 1958, as well as measurements at Byrd Station in Dec. 1958 are discussed. The hole at Little America V reached 836 ft, and core recovery was 98% of the footage drilled. No saline ice was found in the bottom core, indicating that the bottom ice is melting. In detailed stratigraphic studies made to a depth of 53 m, summer snow deposits were coarse-grained and often associated with icy crusts, ice layers, and glands. Winter deposits were finer-grained, more homogeneous, and lacked the soaked appearance of summer snow. Periods of 2-3 consecutive years at more or less regular intervals of 10-20 yr show intense ice formation. Layers of foreign material, tentatively indentified as volcanic asj, were observed at 172.1 m, 219.4 m, and 222.8 m. The depth-density curve steepened between 20.7 and 36.5 m. If annual precipitation is estimated at 21 cm of water, Little America V rests on about 1225 yr of accumulated snow. Data (some of a preliminary nature) are tabluated and graphed: the depth-density profile to a depth of 53 m; the nature of ice at various depths; ponding water equivalents at Little America V; ice temperature at various deoths at both stations; and depth-inclination measurements as well as the diam-vs-depth curve at Burd Station. The future research program at Little America V is outlined.