AN IMPROVEMENT IN ABIC-MINIMIZING DECONVOLUTION FOR CONTINUOUSLY MEASURED MAGNETIC REMANENCE DATA

Deconvolution of magnetic remanence which has been continuously measur ed along a long-core sample is improved by eliminating the disturbance of severe intensity varialion confined to a narrow laver. The deconvo lution is constrained by the smoothness of the magnetization measured by the L-2-norm of second order difference. The previous model uses a single smoothness parameter for the entire sample and the optimum smoo thness is obtained by minimizing ABIC (Akaike's Bayesian Information C riterion), while an additional parameter is introduced in the modified scheme for a layer where intensity fluctuation is strong, The modifie d deconvolution scheme was applied to 5-mm interval magnetic remanence data for two sections of ODP Hole 767B, We assumed another smoothness for the uppermost 1.5 cm of Section 767B-6H1 where the coring disturb ance is severe, For Section 767B-6H2, the Australasian microtektite la yer (108-113 cm), where the magnetization intensity shows a strong pea k, is expressed by a different smoothness parameter from other part, I n both cases the minimum ABIC was lowered and the calculated error was reduced, demonstrating the improvement of the model by incorporating additional information other than magnetic remanence data in the prior distribution of the data.