Figure F41. Photomicrographs from sediment containing diagenetic "green bands." (A) Plane-polarized light and (B) cross-polarized light images of clayey nannofossil ooze with foraminiferal tests (arrow) containing authigenic smectite clays (note that black dendritic areas are epoxy used to impregnate the soft sediment); the bottom half of each image is within a "green band." (C) plane and (D) polarized light photomicrograph of a burrow in clayey nannofossil ooze filled with volcanic glass. Burrow (arrow; glass is isotropic) shows authigenic smectite (saponite) filling pore spaces and part of foraminifer test.