This figure consists of three QuickTime movies that show progressive serial sections in three mutually orthogonal directions through oppositely concave microfolds in and adjacent to plagioclase porphyroblasts. The data for these movies was collected from parallel serial thin sections of a rock from the Robertson River Metamorphics, North Queensland, Australia. In these movies plagioclase porphyroblasts are green, and the five inclusion-foliation surfaces, which we label S1 in our paper, are variably coloured depending on their orientations. Numbers along the margins indicate true dimensions (mm). There are three plagioclase porphyroblasts present, but the large central one is of most interest.

(a) Sections of the porphyroblasts and foliations in a plane parallel to the top face of Fig. 1 in the paper, which is parallel to the X-Z plane of finite strain. (b) Sections of the porphyroblasts and foliations in a plane parallel to the left-front face of Fig. 1, which is parallel to the X-Y plane of finite strain. (c) Sections of the porphyroblasts and foliations in a plane parallel to the right-front face of Fig. 1, which is parallel to the Y-Z plane of finite strain.

We recommend starting with Fig. 11a, because it sections the microstructure in the best orientation for observing the oppositely concave microfolds. In your movie player, select "loop" or "loop back and forth" from the movie menu, and run the movie. The movie may run too fast for first-time viewers to clearly see the 3-D geometry to be illustrated. If you have difficulty, stopping the movie and operating it manually will help because it allows the speed to be controlled. Using the arrow keys on your keyboard (or mouse) you should be able to advance the movie frame by frame in either direction. The 3-D shapes of the foliations are best seen by concentrating on a single foliation surface until its shape is clear. Then, move on to another foliation surface, and so on, until the entire image makes sense. At this point you can move on to Fig. 11b & c. Figure 11b is the most difficult to see clearly, so it helps to follow individual foliation surfaces while manually running through the frames. This movie, like Fig. 11a, shows oppositely concave microfolds, and seeing them in two perpendicular sections illustrates that they are non-cylindrical, with a sort of bell shape (similar to a sheath fold). The non-cylindrical nature of these microfolds is also illustrated in Fig. 11c, where closed loops are seen in the two end foliation surfaces. These non-cylindrical, oppositely concave microfolds form by heterogeneous extension around the rigid porphyroblast during the development of S2, a process explained in more detail in the paper.