shotsubup.m

基于matlab的反演程序,用于地球物理勘探中射线追踪及偏移成像程序.

% Subtract traveltimes of shot i from j
% i, j = shot numbers
% r = shot location vector
% reclocation = receiver location matrix (shot, rec)
% shotpick = fb pick matrix (shot, rec)
% step = interpolation interval 
function [start1, end1, tdiff1, start2, end2, tdiff2] = shotsubup(i,j,r,reclocation,pickuphole,step)

%traveltime difference between adjacent shot records;

p1 = NaN;
p2 = NaN;

endx = r(j);
startp1x=min(reclocation(i,:));
startp2x=min(reclocation(j,:));
startx = max(startp1x, startp2x);
step=1;
xloc=startx:step:endx;
p1=interp1(reclocation(i,:),pickuphole(i,:),xloc,'linear');
p2=interp1(reclocation(j,:),pickuphole(j,:),xloc,'linear');

tdiff1=p1-p2;
start1 = startx;
end1 = endx;

endp1x=max(reclocation(i,:));
endp2x=max(reclocation(j,:));
endx = min(endp1x, endp2x);
startx = r(i);
xloc=startx:step:endx;
p1=interp1(reclocation(i,:),pickuphole(i,:),xloc,'linear');
p2=interp1(reclocation(j,:),pickuphole(j,:),xloc,'linear');

tdiff2=p2-p1;
start2 = startx;
end2 = endx;