| ADJ Datum
                                                                     | 
                                                                          | Sets active datum
                                                                     | 
                                                            
                                                                | Elevation
                                                                     | 
                                                                          | Drop down sets the active elevation for the well.
                                                                     | 
                                                            
                                                                | Active Only 
                                                                     | Check box
                                                                     | Displays formation tops with active entries only.  Useful for trimming list of tops in large multi-user projects.
                                                                     | 
                                                            
                                                                | Read Only 
                                                                     | Check box
                                                                     | When selected, the formation tops cannot be changed.  This includes manually typing in new values, picking tops in other modules, or being overwritten during import.
                                                                     | 
                                                            
                                                                | Maintenance  
                                                                     | 
                                                                          | Opens Zone Maintenance Tool, which also creates and modifies formation tops.
                                                                     | 
                                                            
                                                                |  New
                                                                     | 
                                                                          | Adds new formation top marker.
                                                                     | 
                                                            
                                                                | Define Top Aliases
                                                                     | 
                                                                          | Opens Define Formation Top Aliases Tool.  This sets how Petra will replace missing tops with other "equivalent" tops in the database.
                                                                     | 
                                                            
                                                                | Reorder/Filter
                                                                     | 
                                                                          
                                                                          
                                                                          | Reorder  opens the Order Z Data Items Tool.  This sets the desired order that tops will appear on the Fm Tops tab and in Petra's modules. 
                                                                     ·Green dot = Tops have been re-ordered
                                                                     ·Red dot = Tops have been both re-ordered and filtered.
                                                                     | 
                                                            
                                                                | Export
                                                                     | 
                                                                          | Exports the FmTops to MS Excel
                                                                     | 
                                                            
                                                                | Print
                                                                     | 
                                                                          | Prints the currently selected well's formation tops.
                                                                     | 
                                                            
                                                                | Fault Gap
                                                                     | 
                                                                          | Opens Fault Cut Tool. Petra can store fault cuts and throw to help in reconstructing the stratigraphic positioning of the lithology.
                                                                     | 
                                                            
                                                                | Filter Source
                                                                     | 
                                                                          | Opens Show Tops by Source Tool.  Formation  limits Formation Tops to only the source or sources selected.  This can be useful for only displaying or   modifying your tops in a large multi user environment.
                                                                     |