How do I specify a specific color for a specific value for velocity in seismic velocity modelling?

x=[-500 500 500 -500 -500];

y=[0 0 -20 -20 0];

fill(x,y,[0.3010 0.7450 0.9330]);

hold on;

y1=[-20 -20 -30 -30 -20];

fill(x,y1,[0.7010 0.7450 0.9330]);

y2=[-30 -30 -50 -50 -30];

fill(x,y2,[0.2010 0.7450 0.130]);

xlabel('Offset');

ylabel('Depth');

title('Velocity Model');

set(gca,'ydir','reverse');set(gca,'xaxislocation','top');

hold off

I have used this code and want to assign the valus of velocity 550 750 1000 for the rectangles respective and add a colorbar with the value of velocity

[Scott MacKenzie]

Are you sure you want to add a colorbar? Perhaps you just want to add a text label (550, 750, or 1000) to each bar. Please clarify, if you can.

[Sumana Mondal]

I want this type of figure

Answer 1

[Scott MacKenzie]

I think this is more or less what you are after. The code includes an example of adding text and a rectangle. You can customize these as per your data and needs.

y = 180:10:340;
c = repmat(y',1,6);
p = pcolor(flip(c));
p.FaceColor = 'interp';
p.LineStyle = 'none';
colormap jet;
cb = colorbar;
cb.Label.String = 'S Velocity (m/s)';

ax = gca;
ax.YDir = 'reverse';
ax.XTickLabel = num2cell(10:10:60);
ax.YTickLabel = num2cell(1:8);
ax.XLabel.String = 'X (m)';
ax.YLabel.String = 'Z (m)';

% examples of adding text and rectangle
text(3.6, 8, 'Example text', 'horizontalalignment', 'center', 'fontsize', 18);
rectangle('position', [2 9 3 2]);