APPENDIX C

Basic Features of the GAR Program

The GAR software allows you to see any of the gas element analysis results for an entire hole. It also is capable of plotting the C1/C2 and the C1/C2+ ratios. Also, the data is available to GAR the minute it is uploaded into the database, so that you can use GAR as a warning tool for undesirably low ratios of C1/C2.

To access GAR, double click on the GAR icon, enter chem104 for the Username and Password, and select Janus as Host. The screen shown in Figure AF1 will appear.

Selecting Data to Be Plotted

GAR uses a standard graphical user interface. However, not all of the features in this screen can be accessed by using the keyboard. A mouse is necessary for any of the graphical controls that allow you to control the scales, resolution, or position of the plots.

Graph Area

The graph area is capable of displaying any of the results from gas element analysis for an entire hole. You will notice the y-axis of the graph area is labeled "Depth (mbsf)" (Fig. AF1). The y-axis is the depth of each data point, given in meters below seafloor (mbsf). The x-axis is the measurement, as given by the by the gas analysis.

The graph area has a several sets of controls placed around it. These controls allow you to select the data to be displayed, modify program operation, and manipulate the display or plot. The graph controls, placed to the left of the graph, are explained in the following section. The operation controls, placed on the lower left corner of GAR's screen, are explained in the section after that.

Graph Controls

The graph controls allow you to select the data you wish displayed on the graph (Fig. AF2).

To select the data to be plotted, follow these steps:

  1. Select the hole for which you wish to obtain a plot. This is done by clicking on your selection from the list of holes with the mouse. You will notice the "*Current*" option in the list of holes. This option automatically finds what the current hole is in the database. This may or may not be the first hole in the list, depending on whether the ship is drilling at a previously visited site.
  2. Select the data type you wish to display. This is done by clicking on your selection from the list of data types.

One of the display types available is the "Element Table." This table will display the actual numbers as shown in Figure AF3. The resulting table shows one sample per row, and after the sample ID, it shows the depth and a column for each of the elements. Unfortunately, there is not enough room on the screen to display all the information. By default, the program will display the top left portion of the table. To the right and below the table, there are scroll bars that you can use to see the rest of the information. To do this, click on the scroll bar with the mouse, hold the mouse button down, and move the mouse in the direction you would like to see more data.

Modifying Program Operation and Alarms

GAR allows you to specify several things about how it operates. These include the frequency with which it should update itself from the database, the level of the selected gas element below which it should give a warning, and the ratio below which it should give an alarm.

Update Interval

Every so often, GAR updates itself from the database. This prompt lets you determine how often this should happen. In the example shown in Figure AF4, the user has chosen an update interval of 600 s. This means that every 10 min, GAR will query the database for the data the user has chosen to display. If any new data has been added or any changes made during those 10 min, GAR will receive the updated data. GAR will update the displayed graph or element table.

Warning Level

When GAR gets the requested data from the database, it checks every value against the number in the Warning Level prompt. If any value for the displayed data goes below the Warning Level value, GAR will display a small yellow message on the top right of the graph, and it will cause the computer to beep. Please note, if you want GAR to warn you of a low C1/C2 ratio, you must select C1/C2 to be displayed. The data displayed is what gets checked against the warning level.

Alarm Level

This works exactly like the Warning Level. However, if any of the data goes below the Alarm Level, GAR will display a bigger red message in the middle of the graph and it will start beeping continuously. Again, you must select the C1/C2 display if you want GAR to give an alarm for low C1/C2 ratios.

Exiting GAR

To exit GAR, click on the exit button located at the bottom corner of the operation controls.

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