

   MMeeaassuurreemmeennttss oonn PPeettrroolleeuumm RRoocckk SSaammpplleess

        data(rock)

   FFoorrmmaatt::

        A data frame with 48 rows and 4 numeric columns.

         [,1]     area      area of pores space, in pixels out of 256 by 256
         [,2]     peri      perimeter in pixels
         [,3]     shape     perimeter/sqrt(area)
         [,4]     perm      permeability in milli-Darcies

   DDeettaaiillss::

        Twelve core samples from petroleum reservoirs were sam-
        pled by 4 cross-sections.  Each core sample was mea-
        sured for permeability, and each cross-section has
        total area of pores, total perimeter of pores, and
        shape.

   SSoouurrccee::

        Data from BP Research, image analysis by Ronit Katz, U.
        Oxford.

