For the past several weeks, Spirit has been examining
spectacular layered rocks exposed at "Home Plate." The rover has
been driving around the northern and eastern edges of Home
Plate, on the way to "McCool Hill." Before departing, Spirit
took this image showing some of the most complex layering
patterns seen so far at this location. The layered nature of
these rocks presents new questions for the rover team. In
addition to their chemical properties, which scientists can
study using Spirit's spectrometers, these rocks record a
detailed history of the physical properties that formed them. In
the center of this image, one group of layers slopes downward to
the right. The layers above and below this group are more nearly
horizontal. Where layers of different orientations intersect,
other layers are truncated. This indicates that there were
complex patterns of alternating erosion and deposition occurring
when these layers were being deposited. Similar patterns can be
found in some sedimentary rocks on Earth. Phys