State Archaeological Investigation of Brickell Point (8DA12)
Report: Week 5, 11/8 through 11/12

Prepared by Ryan J. Wheeler, Archaeologist
Bureau of Archaeological Research, 11/13/99

Many of the projects begun on October 18 are complete or nearing completion. The preliminary results of these projects are presented below:

THEMATIC MAPS
Information obtained from the auger tests and examination of earlier trenches and excavation profiles across the site was used to produce a series of five thematic maps of the property.

Field Map
The first of these is the field map, which was used to plot auger tests and other excavations, as well as earlier excavations and the location of some of the footer removal trenches. This map was constructed from the 12 foot grid data provided by the Miami-Dade County survey crew and other measurements made during the project.

Present Surface Contours
The second map used the elevation data for the 12 foot grid coordinates to draw the present surface contours of the property. These contours reflect the fact that the surface of the property has been radically altered by leveling and construction. Many of the contours correspond to the footer trenches or spoil piles, or other activities associated with the 1998 demolition of the Brickell Point apartment buildings.

Surface Contours of Miami Oolite Formation
This map shows what the property would look like if all construction fill and midden deposits were stripped away. The 0.50 m contour interval corresponds with the historic shoreline of the Miami River. This interpretation is supported by a photograph in the collections of the Historical Museum of Southern Florida, which shows the construction of the concrete bulkhead sometime between 1918 and 1925. Dredge fill was added behind this bulkhead, and this material was observed in the profile of Footer Trench 11. This map also shows that the Miami Circle feature occupied one of the higher points on the property.

Surface Contours of Midden Deposit
This map shows what the property would look like if all the construction and dredge fill were removed, exposing the surface of the midden deposit. What is most obvious from this map is that the surface of the midden has been altered sometime in the past, as considerable portions of midden have been removed, while other areas have extremely thin midden deposits. Despite these modifications, the Miami Circle feature occupies the highest elevation at the site. Note that the site boundary shown on this map is based on data about the distribution of the midden and the limestone, since significant features are present in the bedrock in areas with little or no extant midden deposition.

Midden Thickness
This map shows the current distribution and condition of the intact midden deposits at the Brickell Point site. Note that while many parts of the site contain only thin deposits, between 0 and 20 cm in thickness, there are considerable areas that have between 40 and 60 cm of intact black earth midden deposits. These are mostly present along the downward slope of the old shoreline, as the projected cross-section shows. The thicker midden is probably preserved in this area because it is capped and protected by the dredge fill deposited earlier in the twentieth century. Later clearing and leveling operations probably removed thicker deposits on the southern half of the site.

Summary
While several of these maps document alteration and destruction of portions of the site, it is apparent that significant deposits of midden still remain intact. The current plot indicates that approximately 35 % of the property is covered with midden deposits. The data collected to produce these maps indicate that almost all areas that have the original limestone surface contain solution features and cut holes that contain intact midden deposits. It is estimated that the Brickell Point site occupies about 71 % of the property.

EXCAVATION AROUND SEPTIC TANK
The septic tank chosen for examination was associated with Building 3 of the Brickell Point apartments, and was the northernmost of two tanks. It is one of 14 septic tanks installed in 1950 to serve the Brickell Point apartments; in 1970 the tanks were bridged and filled and the septic system modified and the buildings connected to the city sewer system. This tank is roughly 70 feet west of the septic tank associated with the Miami Circle feature. The septic tank was located with the mechanical auger after consulting the 1970 plan of the Brickell Point apartment's septic system. The tank was exposed with a backhoe. The septic tank had been filled in 1970 with white sand and rubble; much of the area around the tank has a deposit of this material as well. The trench dug for the original installation of the septic tank was apparent when the surface was cleared. The inflow pipe for this tank comes from the west, makes a sharp turn and enters the north end of the tank; the original outflow has been replaced by a bridge pipe and exits the south end of then tank.

Unit West of Septic Tank
Two units have been excavated adjacent to the west and east sides of the southern end of the septic tank. The western unit is 1.5 meters along its north-south axis and 1 m wide. Fill was removed from the top of the unit by backhoe and by hand. This unit does not contain any evidence of the trench dug for the septic tank, which is visible to the east in plan view. Five levels were dug here, each being 10 cm except the last level, which encountered the irregular limestone bedrock after 4 or 5 cm. A total of around 45 cm of midden was excavated and screened through 1/16" mesh. Several decorated sherds were encountered, including Opa Locka Incised, which dates to Glades IIa (A.D. 750-A.D. 900). The other decorated sherd has not been identified, but may be related to Safety Harbor or Fort Walton types. The limestone surface was covered with a layer of Lucine clam shells and other shells-in some places these are cemented to the limestone along with bone and other midden material. Several small holes were found in the limestone surface, but no large basins, like those that form the Miami Circle feature, were encountered. The limestone surface was preserved under the midden, and there was no evidence of contemporary disturbance. A 50 x 50 cm column sample was taken from the SW portion of this unit and retained for future analysis. Other finds from this unit include bone artifact fragments, shell artifact fragments, plain pottery, and a considerable collection of faunal material, including the auditory bulla of a whale.

Unit East of Septic Tank
The 1 x 1 m unit excavated to the east of the septic tank had considerable evidence of tree root disturbance. Consultation of a plan of the property made in the 1990s indicates that a 42 inch tree was located in this area. This unit only had 30 to 35 cm of midden before the bedrock was reached. Like its counterpart to the west, this unit produced a sherd of Opa Locka Incised. The trench dug for placement of the septic tank is very obvious in the western part of this unit, and was excavated separately. The trench fill consists of compact sand, crushed limestone, and concrete block fragments. At least one hole in the limestone has been noted here. The eastern portion of this unit is still underway.

Summary
While excavations in this area are still continuing, it is important to note that no evidence for another circle, like the one already excavated and dubbed the "Miami Circle," has been found. Presumably this evidence would consist of the large basins and associated holes that compose the circular feature. We placed our excavations in areas that would have encountered these basins had they been associated with the septic tank that we have examined. Instead we found the trench cut through the midden and the underlying limestone for placement of the septic tank, with intact midden deposits to the sides and intact limestone bedrock under this.

"VALLEY OF THE HOLES"
At the present an area 4.5 meters north-south by 2.2 meters east west has been uncovered (about 10 square meters). Thirty-three (33) distinct features have been identified here, including two (2) large basin-like troughs or depressions, four (4) "double" or connected holes, four (4) sets or pairs of holes placed close together, twenty-one (21) single holes cut in the limestone, and what appear to be two (2) aborted or abandoned holes.

The former features are interesting since they give some indication of the aboriginal process of making one of the cut holes. These are circular depressions, chopped into the surface of the limestone, and then apparently abandoned with no further modification.

Close examination of the cut holes in this area indicate that many (if not all) have a thin (1 to 2 mm) indurated crust on the limestone surface extending down into the hole. This is in contrast to the unaltered limestone surface around the holes, which has an indurated crust ranging from 8 to 10 mm. In some places near the cut holes, this crust has been broken or spalled off in antiquity, perhaps when the cut holes were originally made.

Cut hole feature "R" is a good example of the "double" holes encountered in this area. The brown, disturbed layer at the surface of the limestone contained a sherd of whiteware or white ironstone, probably dating to the late nineteenth century. The midden removed from the double holes cut in the limestone did not contain any historic material, and was tightly packed in the hole. At 12 cm below the surface of the limestone a sherd of Opa Locka Incised pottery was found. The bottom of the hole was filled with concreted midden. In all, the hole was probably around 25 cm in depth. Like many of the other holes, the sides were straight until around 10 cm below the limestone surface, from here the paired holes tapered gradually to the bottom, with a slight ridge separating the two holes.

Several interesting artifacts from this area include examples of Opa Locka Incised and Miami Incised pottery sherds; both of these types date to Glades IIa (A.D. 750-A.D. 900). Other Opa Locka Incised sherds were encountered in the excavations around the septic tank described above. Other artifacts include fragments of bone tools and modified shark tooth tools, as well as an interesting stone bead. This bead has flattened ends and slightly bulging sides, an off-center countersunk hole, is 6 mm high, 20 cm wide, and appears to be made of a non-local mineral, perhaps galena (lead sulphide). The surface is a shiny, metallic gray color, and the distinct cleavage of this mineral is notable. Galena deposits are found in southeastern Missouri, the Missouri-Kansas-Oklahoma area, and in Illinois and Wisconsin. Like the basalt axes found during excavations of the Miami Circle, this bead points to participation in long-distance exchange.

NINETEENTH CENTURY MATERIAL
Several areas across the site have produced nineteenth century artifacts, including glass bottle fragments, square cut nails, whiteware sherds, and occasional glass trade beads.

This material is usually found in a matrix of brown, redeposited midden, which often includes aboriginal pottery sherds, and degraded bone and shell. This layer is usually thin, ranging from 1 cm to 8 cm in thickness. We have encountered this layer in many of our excavations, either below the fill and above the limestone, or on top of the intact midden deposits.

In the "Valley of the Holes" this layer occurs below a compact layer of fill and limestone cobbles (both Miami Oolite and Anastasia Coquina limestone) and above the limestone bedrock. This layer intrudes slightly into the very top of some of the cut holes in this area. For example, cut hole "Q" had the base of a green glass bottle pressed into the sediment in the top of the hole-nothing below this contained any historic material.

This brown layer extended well into a trough-like depression, labeled "V." Material removed from the disturbed portion of this unit includes cut nails, whiteware sherds, green bottle glass, coal slag, and two faceted Russian blue bead.

Temporally this material probably dates from circa 1840 through 1890, and may be associated with the Brickell occupation of the property. The material probably became incorporated in the site in its current form during some leveling and clearing event that mixed the aboriginal midden with the historic material and then spread it thinly over large portions of the property.

SUMMARY
The results presented above compare well with and complement the report prepared by Brent Weisman, George Luer and Herschel Shepard, as well as information about previous excavations provided by Robert Carr (Archaeological and Historical Conservancy) and John Ricisak (Miami-Dade County Historic Preservation Division). The information about the extent of the site and the extent of the midden deposit help to put the Miami Circle feature in the context of this northernmost portion of the Brickell Point site (8DA12). Significant deposits of midden, ranging between 40 and 60 cm occur in some parts of the site, with thinner deposits elsewhere; in all, the midden deposits were found across 35 % of the property. The limestone surface, occupying roughly 71 % of the property, contains cut holes and solution features that are also filled with intact midden deposits. The discovery of cut holes across the property, and the high concentration of these holes in some areas, are similar to the post mold patterns found at many sites in the Glades Area. The apparent randomness of these holes probably reflects the style of aboriginal architecture in this area, and the occupation of the site over many generations. No distinctive patterns of the cut holes, like those of the Miami Circle feature, have been identified, though they may be present. The deposits examined during this investigation of the site date to the Glades IIa (A.D. 750-A.D. 900) and Glades IIb (A.D. 900-A.D. 1100) periods, with some indications of the nineteenth century occupation of the property. Radiocarbon dates associated with the Miami Circle are considerably earlier.