J. Grotzinger

4) Matrix lam_Spheroid Halos.  This MI Image shows, in the upper left,
    how the inferred grains might be arranged in planes (lines in this
    2D view) to create the lamination observed in the Pancam images.
    This MI image also shows a zone around two spheroids in the upper
    right corner in which the granularity of the matrix is modified.
    In the upper spheroid the grain size of the matrix is increased.
    This change in granularity might represent a "reaction rim",
    produced as a result of fluid interaction within the adjacent
    matrix during growth of the spheroid.