Hydrocamp 2010

 

Water Column manual

 

 

 

 

By

 

Hesham Elhegazy

  

 

 

 12 Oct, 2010





 

 

Contents

1.      Locate the position of interest in the line using the vertical profile (.vert_prof): 2

2.      Open the (.merged) line in swathed: 3

3.      How to use the Water Column tool: 4

4.      Create a 3D movie for the vessel “rotating” and “moving along”: 5

 

1.      Locate the position of interest in the line using the vertical profile (.vert_prof):

 

After unraveling the data, go to the merged file

 

Use the following command to view the vertical profile of the line:

 

jview   –seis   line name.vert_prof

 

This command will open the line in vertical profile.


 

Figure 1 vertical profile

 

Position the mouse on the line. Click and drag a square to zoom in. Another window will open showing a zoomed section of the line.

 


Figure 2 Vertical profile cross section

 

Use left and right arrows on the keyboard to move through the line and see all of it.

 

When you find the area of interest, click the middle mouse button, this will show x and y values for this point.  Write down the x value, exit.

 


Figure 3 The x value in the vertical profile

2.      Open the (.merged) line in swathed:

 

 swathed   line name.merged

 

Fig.4A: Find the location of x that you wrote down in the last step by using the space bar. The X value can be seen in the window (Fig.14C)

 

Figure 4  A) The time series                                                                   B) swath side view                                                  C) heading, roll, pitch and heave window

Fig.4B: In the side view of the swath, position the mouse on it and move through the 80 pings-ping by ping- using the left and right arrows on the key board to find the exact X or sw value (Fig.5)

 

Figure 5  number of swath

3.      How to use the Water Column tool:

 

 Click the WC button located on the top left side of the swathed window (Fig.6)

 


Figure 6  Water column tool

 

Water column tool will process the pings till the ping number that you have chosen in swath window.

 


Figure 7  water column window

(Fig.8) The yellow half circle and line can be controlled using the left, right arrows and up, down arrow respectively.  When both meet in one point, you can see the frequency of this point in the frequency section of the water column window.

 


 Figure 8

 

Buttons:

 

4.      Create a 3D movie for the vessel “rotating” and “moving along”:

 

Press the 3D Widget



Figure 9  3D widget button

 

 


  Figure 10: 3D widget view

 

 

 

Use the following options to adjust the vessel and the beams position, just by positioning the mouse on the function and use left and right arrow on the key board.

 

Functions:

 

 

Buttons:

 

 

Use the “r” key on the keyboard to create rotation images, and “w” to create the drive along images.

This will create ppm images in your file.

 

Exit water column tool

 

Create a new file for the ppm’s:

  mkdir  file name

 

Move all ppm’s inside this file:

 mv  *.ppm

 

Create an animated gif for “rotation”:

convert   -loop 0  -delay 25  3dim_azi*.ppm  name.gif

 

Create an animated gif for “drive along”:

convert   -loop 0  -delay 25  3dim_scan*.ppm  name.gif

 

Open the animated gif using web browser:

web browser name  file name.gif

 

 

Figure 11  Rotating

 

 

Figure 12  Drive along

 

 

Short cuts when using the water column tool: