Identifying distribution of lithologies

[m.bates]

Is there a way of showing boreholes in which a particular type of sediment is present. I am working on a large set of boreholes (c.580) some of which contain peat that is defined as separate units in the lithology table. Is there any way that I can get the software to show me the distribution of those holes with peat (or any other lithology type) on top of say a surface of an underlying stratigraphic unit.

Secondly this data set has been divided into 9 stratigraphic units for correlation. Can I create solid models that for example only show the oldest stratigraphic unit or show only the 3 oldest units?

Thanks,

martin (geoarchaeologist)

[Molly]

In the current version of RockWorks (2004) there is no way to activate only those borings that list a particular lithotype or stratigraphic unit.

One option, for stratigraphy, might be to use the File / Transfer tool to view in the Geological Utilities datasheet a listing of all of your boreholes and the elevations for each unit - those with blanks don't have that unit defined. You can sort that listing there (right-click/Rows/Sort), delete applicable rows, and generate point maps using the Map / EZ Map tool so show locations where such-and-such formation(s) are present.

(Borehole queries based on lithology or stratigraphy will be available in RockWorks2006, which will be released next spring. It will be database-based (MDB), offering a variety of such data queries.)

Re: your second question, yes. Using the Stratigraphy / Model tool, the program will generate a 3-dimensional view of the units' tops and bases (as surfaces with side panels) - you can interactively turn these units and pieces on/off in the RockPlot3D window. For sections, profiles, and fences, you can trick the program into not displaying specific surfaces by creating another version of your stratigraphy table, with those units missing. This assumes you've already created a stratigraphic model AND that the Interpolate Surfaces setting in those dialogs is UNchecked.

If you prefer an actual solid model rather than a stratigraphy model (see the Help messages for a discussion of the difference) you can insert a check in the Save Model check-box, and a MOD file will be saved on disk as the stratigraphic surface model is built. In this solid model, the voxels are assigned a "G" value based on the "G" value you declared for each unit in the stratigraphy table. This solid model can be filtered using the tools in the Geological Utilities Solid / Filter menu.

Molly