(a) Upward propagation of the transverse displacement, as marked with a yellow arrow in each panel, along the spicule trace. The red and brown contours surround the areas with intensities in the top 20% and top 40% of the image, respectively. The vertical coordinates on the right are the heights, with the origin being set at the cusp position ( x = 955 5). This height definition is also adopted in the following figures. (b) Transverse oscillations at the lower section of the spicule trace are shown for a time period ranging from pre-surge through surge to post-surge, with panel (b2) for the surge phase. Yellow box, red and brown contours have the same meaning as panels in (a). Four arrays of red arrows in panels (b1), (b2), (b3), and (b4) represent the oscillations from positions in the current panel toward the positions in the next panel, respectively.