This stop is ~200 m from the pluton margin, where it is in contact with the Meguma Formation. The Meguma is made up of metamorphosed interbedded turbidite sandstones and shales. The pluton margin is apparently less contaminated with local wall rocks that interior portions, despite the fact that xenoliths are abundant. This apparently means that in the margins the xenoliths were frozen in place without complete assimilation. Thin section photos are shown here.
Tiny xenolith, probably of the Meguma Formation. The long axis is approximately vertical in this section.
Several xenoliths of Meguma Formation, with their long axes vertical. This is suggestive of orientation of the xenoliths by magma flow parallel to vertical walls.
Cluster of xenoliths in a coarse-grained clump. This is may be a cluster of xenoliths frozen into coarse-grained part of the pluton margin or roof, which was later detached, transported, and laid to rest in the surrounding more biotite-rich and finer-grained host rock. Alternatively, this may be one of the "breccia pipes/dykes" mentioned in the guidebook. I missed that part of the presentation on the outcrop.
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