If you wish to use the more detailed geology coverage, it will have the name
GEOUNITS in /usr/data/pen/data. It differs a bit from GEOLOGY in that UCODE
is a new item which identifies the actual stratigraphic unit of the rock.
I've incorporated TYPE-ID as well to be as similar as possible to the old
coverage. However TYPE-ID is defined as 2 5 B to save space. See
GEOUNITS.EXP for what everything represents. Note that MATERIAL is a
descriptive name for TYPE-ID as before, but you also have UNIT (a character
symbol map label for the geologic units) and UNIT-DESC (a longer description
of the unit).
I'm tempted to drop TYPE-ID from GEOUNITS.PAT since several units may have the
same TYPE-ID (e.g. TYPE-ID of 12 is for 'sandstone' and there are 14 different
units of sandstone in the area). Thus you can't do the same kind of RELATES
with TYPE-ID -- you'd need to do a LINEAR type RELATE. And we'd save space by
using RELATES to get at rock types from the UCODE.
What do you think?
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