Archeologists from Geo-Marine, Inc., were subcontracted through Prewitt and Associates, Inc., of Austin to conduct National Register of Historic Places evaluative testing at archeological site 41TR170, located in Tarrant County, Texas. This work (Geo-Marine project number 30353.06.02) was conducted for the Environmental Affairs Division of the Texas Department of Transportation under contract/work authorization 57524SA006. The archeological remains are located on and in the alluvial terrace of the Clear Fork of the Trinity River, within the proposed 130-meter-wide right-of-way of State Highway 121 in southwestern Fort Worth. The work was conducted to comply with Section 106 of the National Historic Preservation Act of 1969, as amended (Public Law 89-665); the Department of Transportation Act of 1966 (Public Law 89-670); and the Antiquities Code of Texas, as incorporated into Title 98, Chapter 191, of the Natural Resources Code of Texas of 1977, as amended. The work was conducted under Texas Antiquities Permit Number 3699 issued by the Texas Historical Commission.

A three-stage field tactic was used during the testing of the site. Stage 1, conducted between March 15 and 29, 2005, consisted of archeological monitoring of the mechanical excavation of 28 backhoe trenches, followed by geomorphological field studies of the trench profiles. Trenches were placed both north and south of a relic channel of the Clear Fork of the Trinity River; the present channel was formed in the late 1960s by river-straightening channelization efforts. Efforts were made to ensure archeological sampling of all feature- and artifact-bearing areas previously identified in trenches dug during the 2000 archeological survey. The second stage, which occurred between March 21 and April 29, 2005, involved the manual excavation of 10 test units to depths of 2 meters below surface using standard 10-centimeter-thick levels. The purpose of this phase was to assess the reliability of the backhoe trench monitoring activities and to locate occupation zones worthy of further excavations. The third stage of field investigations was conducted between May 2 and June 3, 2005, and consisted of the mechanical stripping of the overburden above target occupation surfaces and the manual excavation of three block excavations, each 9 square meters, to a depth of 40 centimeters below surface. Upon completion of the fieldwork, a fourth stage comprised a limited analysis to document the nature of the recovered assemblage and to make National Register recommendations about the site, and a final stage was to design a plan for further study or analysis that would then be based on the results of an interim report.

The geomorphic investigations, coupled with the processing of eight radiocarbon dates, ascertained that the upper 2 meters of the Clear Fork sediments date to the past 2,900 years. All trenches contained evidence of the regionally dominant West Fork paleosol that is buried under a thin layer of recent alluvium. Beneath the West Fork paleosol were grayish and yellowish clayey strata, and stringers of pea-sized gravels could be correlated to many of the trenches onsite. The substrate for a series of trenches dug into the south edge of the site encountered cemented gravels that likely date to the Pleistocene age. These gravels extend above the Holocene alluvial sediments onsite and provide some minor relief above the floodplain. Although some bioturbation has blurred boundaries between the West Fork paleosol and more recent sediments, the degree of sediment movement is not as pronounced as observed in many other parts of Texas.

The excavations generally documented a series of low-density, highly stratified occupations that could not be correlated with any great assurance. The site context and integrity of deposits are generally excellent. Nevertheless, the paucity of remains in most areas is generally insufficient to provide data necessary to address many regional research questions. Site 41TR170 is not unique in this regard, because many sites within the Trinity River basin seem to be short-term specialized logistical extractive activity areas rather than campsites. Two areas of 41TR170, however, seem to be exceptions to low-density, brief occupations and contain a range of features unlike any previously encountered or recorded in the Clear Fork of the Trinity River.

In an area located about 60 meters north of the relic river channel, Block 2 exposed part of a deeply buried (180–220 centimeters below surface) ashy zone with abundant charcoal flecks and burned clay daub that occasionally retained impressions of sticks and small posts. Three burned rock features (small pits, scattered rocks, and rock dump concentrations) were found within this ashy zone, but they were not associated with the genesis of the ash. Bone preservation in this zone was good (numbering 121 specimens), but only one stone tool and four pieces of manufacture/maintenance debris were found. Based on the stratigraphic position and the recovery of one unclassified dart point, this feature is possibly Transitional Archaic in affiliation. Indeed, four radiocarbon dates from two features and the top and bottom of the ashy zone reaffirm that the occupation dates between A.D. 540 and 710 (two sigma dates, tree-ring calibrated), and relates to the Transitional Archaic period. The genesis of the thick ashy zone is problematic and not well understood. The radiocarbon dates suggest that the 40-centimeter-thick ashy zone did not develop instantaneously but rather apparently accumulated over a span of about 180 years (ca. 1,270 and 1,450 years ago). Even though a few rock features and some relatively high density of bone are preserved in this ashy sediment, the low density of remains suggests that the deposit cannot be considered an occupation midden. The age range also suggests that this is not a burned architectural structure. The formation process resulting in a 40-centimeter-thick ashy zone remains unknown.

In an area almost 150 meters south of the relic channel, an extensive area of burned rock covering at least 12-x-12 meters was encountered. Noncontiguous Blocks 1 and 3 were opened to explore the variability of burned rock features and ascertain the kinds of remains present. The recovery of two dart points (a Trinity and a Yarbrough) at comparable depths of 90 to 130 centimeters below surface suggests that this area along the edge of the Pleistocene gravel terrace was repeatedly occupied during the Late Archaic period. Among the burned rock features revealed in Block 3 was one large incipient burned rock oven with a pit measuring 2.54 meters in diameter surrounded by a discard ring of burned rocks that were only some 20 centimeters thick. Another cluster of burned rock more deeply buried in the sediments suggests multiple occupations. In adjacent Block 1 were two smaller (possible) pit ovens about 1 meter in diameter, an elongated pile of rock stored for reuse, a few rake-off piles or dumps, and one area of fitted burned rock that might have served as a large griddle-like feature. Tools and chipped stone debris were moderately abundant in Block 1, but rare in Block 3. Bone preservation in this area was very poor, although several hundred fragments of scattered freshwater mussel shell were present. Analysis of shell umbos or hinges indicates that about 59 shells were present in Block 1 and only 50 hinges in Block 3; none were concentrated into discrete discard features. The size, density, and morphological variability of the burned rock features are unlike anything previously seen in the Trinity River basin. Four radiocarbon dates from Blocks 1 and 3 suggest that the series of occupations date between A.D. 540 and 780 (2-sigma dates, tree-ring calibrated). Indeed the radiocarbon dates indicate that the activities resulting in the accumulation of dense burned rock features exposed in Blocks 1 and 3 are culturally contemporaneous with the activities occurring in the thick ashy zone located some 170 to 210 meters apart, even though they undoubtedly represent multiple reuse of the area. The two areas may not have been occupied simultaneously, for the low artifact density suggests that comparable groups of people from the Transitional Archaic period made the distinctly different occupational signatures in the two areas.

The testing phase of work at 41TR170 has documented considerable variability in feature forms during the Transitional Archaic period for the Trinity River basin. Test probes also strongly suggest that many more burned rock features occur parallel to the Pleistocene gravel terrace. In this regard, the testing has not exhausted the information potential related to the spatial patterning in activities by these people. However, the associated stone, shell, and bone artifact assemblages are relatively meager. Similarly, extensive flotation has failed to find any macrobotanical remains other than a single nutshell and small amounts of wood charcoal. Efforts to retrieve lipids samples from the burned rock feature proved to be successful, but the results were not very helpful in providing insight into the diversity of feature activities. Although examination of more burned rock features may stumble on examples of cooking accidents that preserve ancient foodstuff, the current robust level of testing suggests that the information content from the site is relatively limited. For this reason, even though the site is of considerable interest from a regional perspective, the site seemingly does not have the potential to make further contributions to the knowledge of the region. Thus, site 41TR170 fails to meet the standards of Criterion D or any other significance standard required for assessing National Register eligibility. Site 41TR170 is recommended as not eligible for National Register inclusion, and no further archeological investigations are recommended.

Licensing Statement

This is a work for hire produced for the Texas Department of Transportation (TxDOT), which owns all rights, title, and interest in and to all data and other information developed for this project under its contract with the report producer. The report may be cited and brief passages from this publication may be reproduced without permission provided that credit is given to TxDOT and the firm that produced it. Permission to reprint an entire chapter, section, figures or tables must be obtained in advance from the Supervisor of the Archeological Studies Branch, Environmental Affairs Division, Texas Department of Transportation, 125 East 11th Street, Austin, Texas, 78701.


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