Combining layers for single coverage area

I have several groups of seismic surveys for which I am creating coverage areas. I am using
EDIT_VECTOR ATTR_VAL="<Feature Name>=%FNAME_WO_EXT%" CREATE_COVERAGE_AREAS=YES
which does almost exactly what I want. The source and receiver coordinates are in separate files, and so get read into separate layers. I then get 2 coverage areas, one for sources and one for receivers. How can I generate one area that shows the coverage of both?
EDIT_VECTOR ATTR_VAL="<Feature Name>=%FNAME_WO_EXT%" CREATE_COVERAGE_AREAS=YES
which does almost exactly what I want. The source and receiver coordinates are in separate files, and so get read into separate layers. I then get 2 coverage areas, one for sources and one for receivers. How can I generate one area that shows the coverage of both?
Comments
Thanks,
Mike
Global Mapper Guru
gmsupport@bluemarblegeo.com
Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation