Plats of Miami Circle Excavations

THE WEST TRENCH EXTENSION is an exploratory trench extended westward from the Main Basin-Circle perimeter. It confirms continuance of the smaller random-size and randomly-distributed holes, but with some tendency to diminish in frequency. On its North Wall face near the opening to the Circle, could be seen a broken sub-surface pipeline; further down this same face - a sand-fraction sample for grain analysis was taken. Natural dips and worn depressions mark the surface here just as as in the Main Circle area and the opposing East Trench Extension. The so-called "Riggs Line" (Solstice Sighting Line) is indicated by a (fortuitous?) line-up of two holes. This line "extends" across the Circle and was picked up in the East Trench Extension (which see). Black indicates excavated features.

THE EAST TRENCH EXTENSION, as its counterpart to the west, is an exploratory probe which confirms continuance of holes and one rather large "sub-basin" to the East beneath the midden. Visible in my plat is the crossing at depth of a 9-inch intact sanitary soil line (bell-ended), in (another?) dug trench (outline). There is a large, deep natural basin just west of this line and just beyond it, is the locus of one test hole percussively formed with replicated tools in the field. Near the opening from the Circle proper, expanses of laminate on the surface of the Oolite were visible at the time of exposure. "Solstice Line" as per previous caption. Plotting order-of-validity is hand-stretched tapes, supplemented by minimal instrument leveling.

THE MAIN CIRCLE PLAT has been derived from photometric measurements and projections. The true shapes of the basins, to the extent possible, have been painstakingly preserved; data for the SE quadrant generally of slightly lower order, as well as possibly some disputed placements where the basins cross or lie in the easternmost footing (?) trench. There is some tendency for basins in the NW quadrant to show a "neck" or narrow extension projecting to the west. This section also flanked on its immediate exterior side by a "row" of "solution pits" or as they have been called, "postholes". A similar run may be seen along the outer periphery of the basins in the SSE sector. The small "solution pits" and secondary holes (all types) within and adjoining the excavated area around the Circle were not plotted <2.5 in. Beyond that, shadow artifacts occur. At this level, some shadow depressions are inescapable. Dashed (green) lines delineate (east to west): modern (<60 years) an empty footing or drain trench; a footing wall (left intact by us) and at the south boundary, the intrusive septic tank. Red denotes cobbles found in situ in the basins as uncovered; there is a greater tendency for these to occur in the SE quadrant. Hachuring denotes vague depressed areas in the Oolite surface.