Study of the texture and fabric in the Taylor Dome ice core.

DI PRINZIO, CARLOS LEONARDO

Ohio University Athens Ohio USA

Jornada; Ohio University Meeting; 2004

Ohio Univestity

A fully automated digital instrument for fabric analysis developed by Hansen and Wilen (2000) increases the quality and the quantity of c-axis fabric data from ice cores. The new data permit different mechanical and physical process in the ice cores to be studied statistically. Software tools are applied to analyze the textures and the fabrics in vertical and horizontal samples from Taylor Dome ice cores in the range 0 to 600 meters.The results show that the grain size increases with depth until the Holocene- Wisconsin boundary. The grain size distributions are very similar among all samples in the Taylor Dome ice core and the evolution of grain size in this depth range is consistent with the normal grain growth process.The samples exhibit correlation among nearest neighbors but their values are lower than the correlation in the GISP2 ice. Recrystallization is not particularly active, possibly because the temperature of the ice cores is lower than –40oC (Alley, 1998). Hence, the results suggest that grain growth is the dominant mechanism to change the size of the grains. The samples exhibit a distinct band in the Schmidt Plot indicative of the stress state in the ice. On average, the maximum elongation direction of the crystal grains is oriented perpendicular to the band in the plot. The results from Taylor Dome are compared with other ice cores in order to understand the different mechanical processes in the ice.