HG 238.80-238.90 Thin Section

Dark brown sediment with clasts ranging from small to medium in size and sub-angular to angular. Contains lineations and grain stacking throughout the sample. Rotation and comet structures can also be seen. Rotation structures can be seen around mainly the sub-angular clasts. Patches of clay can also be seen throughout the sample.

HG 367.80-367.90

Dark grey sediment with clasts that range from small to medium. The clasts are mainly sub-rounded. Lineations are abundant with minor amounts of rotation structures and comet structures. Grain crushing can also be seen throughout the sample.

HG 493.80-493.90

Coarse brown sediment, with clasts ranging from small to large in size. Clast shape ranges from sub-angular to rounded. Lineations and grain crushing are common throughout the sample. It also contains comet structures and a few rotation structures. Many of the larger clasts are also fractured.

HG 64.80-64.90

Dark brown sediment with clasts ranging from small to large in size. The clast shape ranges from angular to sub-rounded. Many of the larger clasts are fractured. Grain crushing is abundant throughout the sample. A few lineations can also be seen throughout the sample.

The crystal and molecular structure of 18-Crown-6 HgC12 and 18-Crown-6 Cdc12

Hg(18-Crown-6)C12 and Cd(18-Crown-6)C12 are isostructura1, space group Cl~ Z = 2. For the mercury compound, a = 10.444(2) A° , b = 11. 468(1) A° , c = 7.754(1) A° , a = 90.06(1)°, B = 82.20(1)°, Y = 90.07(1)°, Dobs = 1.87, Dca1c = 1.93, V = 920.05 13, R = 4.66%. For the cadmium compound, 000 a = 10.374(1) A, b = 11.419(2) A, c = 7.729(1) A, a = 89.95(1)°, B = 81.86(2)°, Y = 89.99(1)°, Dobs = 1.61, Dcalc = 1.64, V = 906.4613, R = 3.95%. The mercury and cadmium ions exhibit hexagonal bipyramidal coordination, with the metal ion located on a centre of symmetry in the plane of the oxygen atoms. The main differences between the two structures are an increase in the metal-oxygen distance and a reduction in the metalchloride distance when the central ion changes from Cd2+ to Hg2+. These differences may be explained in terms of the differences in hardness or softness of the metal ions and the donor atoms.