Operation 43

Patterns underlying the arrangement of buildings in Op. 43 are difficult to discern. The five largest edifices in the area (Strs. 1C-1, 1C-2, 1C-4, AK, and AJ) define a patio immediately south of the central, and largest, depression. Structure AL and rock concentration (RC.) AM may be outliers of this aggregate. Otherwise, buildings are scattered without apparent patio foci between the northwestern and central declivity and east of the southeastern depression. Distinguishing structures from slight undulations in the terrace surface proved difficult when Op. 43 was mapped. We tended, therefore, to take a conservative approach, designating as structures only those surface-visible features that were characterized by relatively clear wall lines. Excavations conducted in 1995 and 1996 amply revealed the error of our ways, uncovering edifices that had been missed during the initial survey. Despite these additions to the architectural corpus, the perceived distribution remains the same; i.e., a patio-focused group in the south composed of relatively substantial buildings contrasted with a scattering of much smaller constructions concentrated on the margins of the depressions.

Investigations within Op. 43 concentrated on the two largest depressions (the central and southeastern examples) and their immediate environs. Work conducted in 1995 (Subops. 43A/G, directed by C. Wells) focused on the central declivity and its western margins. Four buildings (Str. 1C-1 and three edifices not mapped as distinct structures) on the western and southern edges of the depression were excavated along with 35, 1x1m, test pits sunk into the declivity, for a total of 164m2 cleared. Work resumed in Op.43 during 1996, this time centered on the southeastern depression (Subops. 43I-M, supervised by B. Shade). Two previously unrecognized buildings, located within the extensive rock concentration on the declivity's eastern border, were revealed at the same time that 33 test pits, each measuring 1x1m, were dug cross-cutting the depression. A total of 67.5m2 were cleared as a result of the 1996 investigations. C. Wells provides a detailed account of his 1995 research in the environs of the Central depression (1996). The interpretations that follow differ slightly from the views expressed in that report, but do not challenge his essential findings.


Structure AO (Figures **-**) [1 section, 1 plan {1:100}, 1 plan {1:10}; D96-96]

Structure AO appeared on the surface as a slightly denser concentrations of stones within an extensive, diffuse distribution of rocks on the eastern margin of the southeastern depression. The building is situated well upslope within the declivity, near the latter's eastern lip. Structure AN is 7.1m to the north, also on the declivity's eastern edge. Fully 8.5m2 was cleared in revealing the entirety of Str. AO (Subop. 43L), excavations being pursued to a maximum depth of 0.68m below modern ground surface outside construction. A single building phase was recognized in the course of this work directed by B. Shade.

Time Span 1

Stratum 1, a dark grayish-brown (10YR-4/2), moderately hard-compacted clay, is the only soil level identified in Subop. 43L. This earth layer underlies construction by at least 0.6m; its base is outside excavation limits. Recovery of significant quantities of artifacts, especially sherds, from those portions of S.1 below architecture implies a substantial human presence in the immediate area predating Str.AO-1st's erection.

Time Span 2

Structure AO-1st is a surface-level edifice the perimeters of which were originally defined by U.1-4, walls composed of a mixture of unmodified stones and cut tuff blocks set on end. Unit 1, the western perimeter construction, is fashioned exclusively of tuff blocks, U.3, on the south, of tuff cobbles, U.2, on the north, from a mixture of blocks and cobbles, while U.4, on the east, seems to have been made exclusively of cobbles. When uncovered, the U.1-4 stones were in various stages of falling outwards, giving the building a splayed appearance. Contained within these bounds is a cobble pavement (U.5). Unit 5 would have rested roughly 0.2m below the tops of the upright U.1-4 stones and covered an area roughly 0.8m on a side. This version of Str. AO-1st measures 1.1x1.2m and is aligned approximately 16 degrees.

Subsequently, the building was expanded eastward through the construction of U.6 and the extension of U.2 and 3. The addition's perimeter walls are built exclusively of cobbles set on end, while the flooring of river-worn stones noted above continues eastward within these walls. Unit 4 may have remained standing at this time, effectively creating two side-by-side diminutive enclosures within Str. AO-1st; the new "room" covers ca. 0.35x0.8m. The building now measures 1.2x1.5m and retains the previous orientation.

All stones in Str. AO-1st construction are set in a brown mud mortar. The four measured cut-blocks have the following dimensions: 0.2x0.4x0.48m, 0.15x0.36x0.37m, 0.14x0.28x0.37m, and 0.18x0.31x0.4m. Cobbles average 0.2x0.25m in size. Only one fragment of obsidian was found within Str. AO-1st, artifacts being more commonly encountered around the building's perimeter.

The significance of U.4 and 9, located southwest of U.1, remains uncertain. The former is a massive cobble wall, 0.72m high by 1.02m wide, that did not continue across the 1m width of the Subop. 43K northeast-southwest axial trench; it was exposed solely in the northwest trench wall. Unit 4 is backed over the 0.7m separating it from U.1 on the northeast by a fill composed of densely packed, flat-laid medium to small cobbles set in a dark brown clay matrix (U.9). Unit 9 covers U.1, extending from the latter's top to an undetermined point below that wall's base (continuing at least 0.15m below the bottom of U.1). Construction of U.4 and 9, therefore, predates the raising of U.1. It may well be that these entities are parts of a ca. 1.7m wide terrace intended to bolster Str. AN-2nd's downsloping side and to create an elevated living/working space perched above the depression's upper ascents. Unit 1, the building's southwestern footing, would then have been set on to U.9 fill, retained by U.4. Working within this interpretive framework, we would attribute U.4's spotty preservation to post-abandonment disruptive processes, e.g., erosion and/or stone-robbing.

All Str. AN-2nd architectural components are fashioned of unmodified river cobbles bound together with a brown mud mortar. No horizontal courses were noted and only U.2 possessed rocks that were generally placed with their naturally flatter aspects oriented outwards (to the southeast in this case). Overall, Str. AN-2nd conveys an impression of casual construction. Rock sizes average between 0.15x0.2m to 0.22x0.24m.

The changes in construction and orientation noted in U.5, coupled with its relation to U.3, suggests that the former construction was added late in Str. AN's occupation sequence, linking it to possibly three previously distinct buildings to the north (each corresponding to a shift in U.5's construction and alignment). The presence of the steps/terraces on the north implies that the entire structure was a platform by this point. The absence of any comparable modifications on the southwest and southeast directly linked to Str. AN-1st suggests that the builders were concerned with creating a united front for their new edifice on the side not facing the declivity. The sporadic use of cut blocks in U.5 supports the notion that Str. AN-1st's eastern flank was intended to be its formal, "public," facade.

Units 10 and 6 are the southwestern and southeastern elements of a casually constructed terrace built further into the depression from Str. AN-1st, probably to slow erosion on the downsloping side where the building was most vulnerable to this process. Units 6 and 10 are each ca. 0.5m wide by 0.2m high. Unit10 is backed on the northeast by a fill composed of cobbles set in a dark brown earth matrix (U.12); U.6 and its immediate environs were insufficiently cleared to determine the nature of the fill intervening between this construction and U.7, ca. 2.5m to the northwest. Unit 4 would have still risen a reconstructed 0.43m above the U.10/12 terrace. Unit 6 and 10's full lengths were not revealed. Unit 10 may well have continued northwest, fronting and preserving the downsloping flanks of the newly united Str. AN-1st, the northeast face of which is fronted by U.5. Units 6 and 10 are built of medium-size river cobbles (averaging 0.18x0.25m), set in a brown mud mortar, and positioned without attention to horizontal courses or the placement of naturally flatter aspects. The latter is oriented roughly 341 degrees, the former being aligned 77 degrees.

Structure AN-1st, therefore, rises 0.31m and 0.63m high on the northeast and southwest, respectively, measures approximately 6.2x7.2m (excluding U. 6 and 10), and is variably aligned from 333-8 degrees. Access to the summit was formalized over the northern part of the eastern flank by the addition of two low risers constructed from a mix of cut blocks and cobbles. We do not know the nature of summit architecture, though it seems likely that it consisted of perishable, probably bajareque, walls raised above an earthen floor.

The Southeast Depression covers ca. 25x38m and ranges in depth from 1.1-1.35m. This basin-shaped declivity is irregularly shaped and bounded by slopes that ascend gradually to the terrace summit. Two perpendicular trenches were laid out to bisect the depression across its approximate center; Subop. 43I extends 42m from the terrace summit on the north to roughly 4m north of the declivity's southern edge (oriented 10 degrees); Subop. 43J intersects Subop. 43I, extending 33m from the west to east depression margins (oriented 280 degrees). Blocks measuring 1x1m were excavated at intervals within these trenches, spacing determined by the nature of encountered deposits and our desire to reconstruct the depression's original profile. Most commonly, two adjacent blocks were dug simultaneously to get a better sense of the stratigraphy and facilitate excavation at increasing depths. A total of 15 blocks were dug to depths of as much as 1.58m below modern ground surface in Subop. 43I, 13 blocks being dug to a maximum depth of 1.51m below ground level in Subop. 43J. In addition to these excavations, five 1x1m blocks were excavated in Subop. 43K, 4.4m southwest of Str. AN, in the quadrant defined by the northern and eastern arms of Subops. 43I and J. These contiguous tests were sunk to maximum depths of 1.9m below modern ground surface to evaluate the unusual stratigraphic relations and dense artifact deposits encountered on the depression's northeast margin. These investigations were intended to: 1.) establish when this portion of the terrace summit had been excavated; 2.) reconstruct the shape and dimensions of the original depression; 3.) and, provide data from which inferences concerning the declivity's function might be made.

Time Span 1

Stratum 1 is a yellowish-brown (10YR-5/3) clay containing variable quantities of sand and, occasionally, sand and gravel lenses. This earth level was exposed to a maximum thickness of 0.76m in block B5 (Subop, 43I) near the declivity's center and was encountered at the base of every excavation carried to sufficient depth within the depression (S.1's base, however, lies outside excavation limits). Though not culturally sterile, artifact frequencies within this entity are considerably lower than those characteristic of overlying soil layers. Some of these items almost certainly percolated downwards through the permeable barrier separating S.1 from the soils covering it. Recovery of Middle Preclassic ceramic diagnostics from S.1, predating by at least a millennium the earliest material unearthed elsewhere in the Southeast Depression, suggests that there was an extensive human presence in the immediate area when this layer was deposited. Most Middle Preclassic ceramics derive from the western and northeastern margins of the depression outside the deepest portion of the ancient excavation. This distribution may reflect the localized nature of early habitation and/or loss of portions of the settlement when the depression was originally dug.

Lenses 0.05-0.16m thick of dark brown (10YR-4/3) clay flecked with white inclusions are incorporated in S.1 near the depression's northern edge (S.5; recorded in blocks B8/9, Subop. 43I). These layers are exposed for no more than 0.42m long and appear more commonly as isolated deposits embedded in S.1. Their significance is uncertain.

No comparable deposits were recorded elsewhere within the Southeast Depression, though S.6 and 7, exposed in block B20 of Subop. 43I, represent another artifact rich trash deposit located approximately 11m north of the declivity's northern edge. Stratum 6, a grayish brown to dark brown (10YR-5/2 and 4/2) ashy soil covers S.1 by 0.29-0.32m and, in turn, grades into S.7, a dark gray (10YR-4/1) ash 0.67-0.8m thick. No soil level intervenes between S.7 and current ground surface. Strata 6 and 7 appear to be remnants of a trash deposit that sealed S.1 by at least 0.96-1.08m (see Subop. 43G).

Strata 6-7, on the one hand, and S.8-9, on the other, are exposed in two areas separated by ca. 23m of unexcavated terrain. Inclusion of both sets of soil levels in the same time span is based, therefore, on their similar stratigraphic relations to S.1, directly overlying this deposit, and the predominance of ceramics diagnostic of the same time period in these widely separated middens (LCLII).

These slight soil variations are not recorded elsewhere in the Southeast Depression excavations, hinting at a localized soil formation processes operating near the declivity's center. It may be that deposition of S.2-4 coincides with the trash accumulation represented by S.6-9. There is insufficient stratigraphic data to confirm or deny the contemporaneity of these processes. The two episodes are placed in different time spans because it was convenient to distinguish between what seem to be two different processes, i.e., purposeful trash deposition and the incidental inclusion of cultural material in soils gradually washing into the Southeast Depression. Whether this potentially significant behavioral distinction also has temporal meaning remains uncertain.

Middle Preclassic diagnostic ceramics comprise a very minor component of materials assigned to TS.1. These sherds, dating to the earliest known valley occupation, most likely washed in from deposits predating S.1 and 2. Items indicative of Late Classic II and, to a lesser extent, I occupation are more common in S.1 and the lowest portions of S.2.

Structure 43-1-2nd, therefore, would have been a surface-level building the rooms of which are defined by cobble footings (U.2-4, 6-7, 10, and 14) 0.15-0.41m high and 0.24-0.56m wide (U.4, the southern foundation, was not fully exposed). This edifice would have contained three relatively large enclosures whose floors are generally surfaced with earth. The eastern room is bounded by U.2-4 and 6, covers approximately 8.7m2, and, contrary to the norm, is partially paved with cobbles (in its southwest corner, U.17). Immediately to the west, two enclosures are located in a north-south line, the northernmost covering ca.3m2 and containing a ca. 0.26m high shelf (U.18) in its southwest corner that measures 1.4m long by 0.5m wide. The southern room encompasses at least 4m2, its southern flank lying beyond excavation limits. Movement among rooms was virtually unimpeded and at least one capacious (0.8m wide) doorway located in the building's north wall provided access to the interior. Structure 43-1-2nd measures a reconstructed 5x6m and is oriented ca. 273 degrees, 30 minutes.

Structure 43-1-1st was created when the northern entryway was sealed, foundations converted into basal facings, and what had been room interiors filled with a dark gray (10YR-3/N; U.12) clay identical to S.2. Unit 12's upper surface probably served as the unpaved summit floor. The structure now stood 0.2-0.4m high, tops of footings that previously divided the interior into distinct enclosures fulfilling the same role on the platform's summit. Addition of U.15 and 16 at this time served to further subdivide summit space, creating a warren of four interconnected cubicles (Rooms I-IV) separated by cobble footings, 0.18-0.36m high by 0.24-0.4m wide, that likely supported bajareque upper walls (U.5-7, 15, and 16). The easternmost room (Room I) runs the full-north-south width of the building, measuring 0.8x4.3m, and was entered through a 1.35m gap between U.4 and 15 in its southwest corner. Said doorway provides direct access to Room II, an L-shaped cubicle that covers approximately 2.3m2 and was accessed through a 0.4m passage on the north formed by the offset lines of U. 5 and 6 (the U.17 floor lies buried beneath Room II). This narrow breach links Rooms II and III, the latter being a more commodious L-shaped room containing ca. 5.5m2. The U.18 shelf may continue to rise 0.05-0.1m above the summit in Room III's southwest corner. Room IV, directly west and south of Room III, was entered through a 0.6m wide passage between U. 6 and 16 that linked these two cubicles. The southern side of Room IV was not clearly defined, the enclosure covering 1.25m east-west by (minimally) 2m north-south. Time restrictions limited investigation of the building's southern flank, and the manner in which U.4 articulates with U.10, the western facing, remains uncertain.

Built against the platform's west flank are two surface-level cubicles (Rooms V and VI) that use U.10 to delimit their eastern side. The cobble foundations outlining Rooms V and VI (U. 8/9 and U.11/13, respectively) are fairly substantial, measuring 0.2-0.38m high by 0.3-0.55m wide. Room V, the northern of the two adjoining enclosures, covers ca. 1.2m2 and could be accessed through a 0.4m wide doorway set in the north wall; Room VI, its southern neighbor, was entered through a 0.55m wide door in its northwest corner and encompasses only 0.6m2. The relatively late temporal placement of Rooms V and VI within the construction sequence is based on the tenuous argument that, if they had been contemporary with the Str. 43-1-1st's surface-level version, they would have been connected to the latter's interior through doors set into U.10. The orientation of known passageways leading outward weakly implies that the adjacent building's interior was already filled in by the time Rooms V and VI were constructed.

In addition to these more-or-less clear construction elements, there are subtle indications that Room III's southern arm (between U. 15 and 16) once contained a shallow pit (F.1). Feature 1 is identified by a localized concentration of stones that diverge from surrounding tumbled architectural debris in being consistently tilted down west-to-east and resting 0.18m below the reconstructed summit surface. No other signs of a pit outline were noted nor is the soil contained within F.1 distinct from the surrounding fill, or S.2, which covers it. Consequently, F.1 is only tentatively identified as a concavity measuring 0.34m across and 0.18m deep. The density of stone found within the putative depression's bounds, coupled with their consistent orientation, suggests that the rocks in question played some role in whatever purpose F.1 might have served. What that function was, and whether the feature is contemporary with Str. 43-1-1st's principal use period or postdates it, remain unknown.

Structure 43-1-1st stands 0.2-0.4m high, retains its earlier orientation and measures, by the conclusion of TS.3, 6x6.2m (including Rooms V and VI). The summit supports four rooms covering 2.3m2, 2.5m2 (minimum), 3.4m2, and 5.5m2, the only built-in furniture being a low stone shelf located in the northern enclosure (Room III). The two surface-level rooms raised against the platform's western flank encompass 1.2m2 and 0.6m2; both lack built-in furniture.

Located 0.2m north of Str. 43-1-1st's northeast corner is a partially uncovered complex consisting of a circular feature and low cobble wall (U. 21 and 20, respectively). Unit 21 is a curved cobble wall ca. 0.1m high and 0.2m wide that defines the southern half of what is probably a circle with an interior diameter of 0.85m. The circle's interior is surfaced with earth. Extending 1m south from the arc's east side is U.20, a comparably tall cobble wall measuring ca. 0.35m across. Units 20 and 21 are not linked to Str. 43-1-1st, though their elevations suggest that the two entities are contemporary. The U.20/21 complex seems to have been part of a surface-level construction the form and dimensions of which are unknown.

Unit 1, therefore, has a diameter of roughly 5m and was raised over a gradual ascent of ca. 0.36m over 4.2m from east to west (indicated by differences in the basal elevations of U.1's eastern and western foundations). The construction is delimited by relatively narrow (0.2-0.75m across) footings on all sides save the south. The, maximally, 2m wide southern portion of U.1 may have served as more than a simple foundation for perishable upper walls, possibly as a shelf. Access to the interior may have been achieved by traversing U.3 and/or stepping over and across the particularly low and narrow eastern and western U.1 wall segments. Unit 1's earthen-floored interior contains large quantities of artifacts, especially pottery sherds, and encompasses roughly 6m2. This space may have been dug down below ground surface in antiquity. This interpretation is suggested by the distribution of tumbled stone architectural debris within this area (F.2). Feature 2 rocks tilt down from U.1's margins towards the interior, many of them coming to rest at level below the flanking walls (especially notable on the west). Many of the F.2 cobbles were even found sitting atop S.1. There is no evidence of post-abandonment processes that might have produced the observed distribution of F.2 stones. We tentatively surmise, therefore, that the floor of U.1's earthen interior was submerged roughly 0.12m below ancient ground level. The putative floor, like the rest of the building, retained the east-to-west ascent of the surrounding terrain, rising a reconstructed 0.25m over a horizontal distance of 3.54m. The general incline noted in U.1's construction approximates the ascent attested to in underlying S.1, implying that the slope over which that ash deposit was laid down remained relatively unchanged between TS.1 and 2.

Units 5-7 define the south, east, and north flanks of a ca. 0.1m high, cobble-faced platform that projects approximately 2.2m east from U.1's northeast edge. This construction vaguely resembles a right triangle, its southern and eastern facings (U.5 and 6) meeting to form a nearly 90 degree angle while the northern flank (U.7) slopes in from the northeast corner westward to its junction with U.1. The low, earthen-floored platform thus formed is wider (1.3m across) on the east than where it joins U.1 on the west (narrowing to 0.6m across). Unit 5 is aligned 96 degrees while U.7 is oriented 76 degrees.

Units 8-10 are three cobble walls that come as close as 0.2m north of U.1 and 0.4m north of U.7. Unit 8 is 0.9m long, 0.2m wide, and is aligned 338 degrees. Units 9 and 10 are two parallel constructions 0.2m east of U.8, consisting of cobble walls less than 0.2m apart. Unit 9, the northern of the two entities, is 1.85m long by 0.65m wide, its southern neighbor running 2.1m long but is only 0.2m wide. Both U.9 and 10 are oriented 76 degrees, paralleling U.7, 0.4m to the south. All three units are 0.08-0.15m high. Units 8-10 are probably foundations incorporated within a complex of surface-level constructions filling in the seemingly open space between Strs. 43-2-1st and 43-3-1st. The form of these edifices, and whether the uncovered elements are parts of the same or distinct construction, remain unknown.

Structure 43-2-1st, therefore, is a circular building measuring ca. 5m across, defined by low cobble footings, and containing a 2m (maximally) wide cobble shelf on the south. The earthen-floored interior of this entity may have been sunk 0.12m below ancient ground surface, this space being accessed across a stone floor recessed into the southern foundation/shelf and/or by stepping over the particularly narrow eastern and western portions of the encircling walls. Two constructions extend eastward from the circle's eastern limits; a ca. 0.1m high, 0.6-1.3m wide, by 2.2m long platform and a cobble wall, located 1.6m south of the platform, that is 0.4m wide, 0.2m high, and 0.6-0.8m long. Lying immediately north of this complex are the remnants of one or more surface-level constructions. All architecture uncovered in Subop. 43B consists primarily of medium-size cobbles set in a brown mud mortar and with their naturally flatter aspects oriented outwards (the U.1 stones have flat face looking both towards the exterior and earthen-floored interior). Cut blocks are scattered throughout U.1; the southern flank of the indent on U.1's west side is faced with masonry blocks.

Units 5, 6, and the room all cluster around enigmatic U.4. Unit 4, occupying the narrow space between U.1 and 5, consists of two adjoining cut stone blocks, slanting down at ca. 45 degree angles from east to west and north to south, converging on their downslope margins. The larger of the two rocks (0.1x0.4x0.42m) is on the east, the smaller (0.09x0.23x0.29m) on the north. A large (0.25x0.41m), flat-laid cobble rests on U.4's eastern margin. Unit 4's base is 0.16-0.41m below, its top 0.04-0.34m above, the bases of neighboring TS.2 constructions. These discrepancies imply that U.4 extends down into a depression around which U.1, 5, and 6 were built. The absence of S.1 at appropriate depths in the putative pit defined by U.4 on the east suggests that this ashy soil level was partially removed during U.4's construction. Unit 4 is subsequently filled with S.2, architectural debris fallen from Str. 43-3-1st (F.2) coming to rest at depths no lower than 0.18m below U.4's top (equivalent to the uppermost points of the two masonry blocks). Though far from clear, U.4's reconstructed depth is 0.28m and it may have measured as much as 1m across east-west by 0.8m north-south.

Structure 43-3-2nd is more a collection of (probably) related but not architecturally integrated small surface- and subsurface-level constructions clustered within an area measuring at least 4x5m. The components were raised over a gradual east-to-west ascent, no effort apparently having been made to level ground surface prior to erecting U.1-7 and F.1 (Feature 1's base, the westernmost TS.2 construction, is 0.53m above that of U.1 on the east). The most distinctive feature of the complex consists of the three (possibly as many as four) stone arcs resting on and containing cobble pavements. Though the three best preserved examples are similarly built and have comparable dimensions (0.66x0.76m, 0.62x0.84m, and 1.4x1.6m), they vary in which way they face and whether or not they are integrated within a larger construction. An earthen-floored room (covering 1.3x1.8m on its interior), delimited by low cobble foundations, incorporates one of the arcs into its western foundation; the other semi-circular entities are scattered to the west and north. All of these elements, in turn, surround what seems to have been an earthen pit defined by three rocks two of which are cut stone blocks that slant down into the depression from the east and north. No distinctive soils or other rocks mark the declivity's boundaries, the depression's dimensions of 0.8x1m across and 0.28m deep being inferred from its few surviving stone components and the position of contemporary architecture and later construction debris.

All TS.2 stone architecture was built using medium to large cobbles (0.14x0.21m to 0.4x0.52m), bound together with a brown mud mortar, and set in a single line. Two cut blocks are incorporated into U.4 and a single masonry fragment was recorded at the U.2/3 junction. In general, some effort was devoted to orienting the naturally flatter aspects of river-worn stones towards the interior of the southern room and the arcs.

Structure 43-3-1st is a surface-level room that overlaps, and is built slightly west (upslope) from, Str. 43-3-2nd. The former apparently began as a single compartment demarcated by cobble foundations that are 0.25-0.4m wide by 0.1-0.2m high (U.8-11). All perimeter walls, save the southern, conform to a common alignment (359/89 degrees; the southern foundation (U.10) is oriented 113 degrees). The enclosure's earthen-floored interior could be attained by passing through a 0.6m wide gap in the eastern footing (U.11). The room itself covers 1.6x3m (measured across the center) and may have contained a bench/shelf built against its south wall. Evidence for the latter construction consists solely of a ca. 0.12m high cobble wall (U.14) that currently describes a sinuous course as it runs between the western and eastern foundations (U.9 and 11). There is no sign of a stone paving backing U.14 on the south and identification of this entity as a bench/shelf facing is admittedly tentative. If it did serve this function, the construction would have been 1.6m long by 0.6-1.4m wide.

Subsequently, Str. 43-3-1st was expanded downslope (eastward) through the addition of U.12 and 13. The latter is a casually built footing that describes a winding course from its corner with U.12 on the north to its junction with U.11 ca. 0.35m north of the latter's southeast corner. Units 11 and 12 are 0.2-0.25m wide by 0.07-0.32m high and enclose an irregularly shaped room that is 3m north-south (measured along U.11) by 0.5-1.2m east-west. A portion of U.6's stone floor may have been incorporated into the enclosure's interior, though this is far from certain. No built-in furniture or other architectural elements were noted in this eastern extension nor is it clear how the building was entered now that the doorway in U.11 no longer faced the exterior. The U.12/13 addition diverges in orientation from the original structure's alignment; the former is sighted 280/188 degrees (not including U.13's sinuous southern portion).

Unit 15 is a wall fragment (uncovered over only 0.8m northwest-southeast) that measures approximately 0.55m across and stands a preserved 0.08m high. Located ca. 0.3m southwest of Str. 43-3-1st's southwest corner and aligned 313 degrees, U.15 is probably part of a foundation for a surface-level construction the remainder of which extends beyond excavation limits.

Structure 43-3-1st, by TS.3's conclusion, is a surface-level edifice defined by low cobble foundations that delimit two long, relatively narrow earthen-floored rooms. The western enclosures encompasses ca. 1.6x3m and may have contained a 0.12m high bench/shelf raised against its southern wall. The eastern cubicle is irregularly shaped, due in large part to the curving portions of its eastern footing, and measures 3m long by 0.5-1.2m wide. Structure 43-3-1st, altogether, covers (maximally) 3.8x4m and is aligned 359 (west) and 188 degrees (east). Like its predecessor, Str. 43-3-1st was raised over an east-to-west ascent; U.13's base on the east is 0.41m lower than that of the western-most building component (U.9). Remnants of at least one more surface-level construction were revealed within 0.3m of Str. 43-3-1st's southwest corner.

Time Span 3 architecture closely resembles constructions dated to TS.2; i.e., foundations and facings (U.14) composed of single to, at most, two rough courses of medium to large cobbles (0.1x0.16m to 0.4x0.45m) set in a brown mud mortar. Some effort was made to place the naturally flatter aspects of stones facing outwards and into room interiors, though this tendency is more strongly attested to in Str. 43-3-1st's original western room than it is in the eastern addition.

Units 1 and 2 are backed by a fill composed of medium to small river cobbles set in a very dark gray clay matrix indistinguishable from S.2 (U.5). Only ca. 0.1m of U.5 was exposed behind (east) of U.2; the deeper probe into U.5 west of U.1 revealed that this fill directly overlies S.1 here. As noted earlier (TS.1), S.1 slopes up east-to-west under the platform and it looks like Str. 1C-1-1st's builders took advantage of this rise to reduce the labor required to raise the edifice. At least some superstructure architecture (U.3 and 4) was erected on S.1's level top while U.5 was packed in only where it was needed over the eastern ascent to level the summit.

Unit 3 is a 2.43m long, 0.6m wide, by 0.43m high (above U.5's inferred top) stone wall that runs approximately east-west near the center of Str. 1C-1-1st's summit. Abutting this wall on the north is a much smaller, more casually built entity that is 0.3m wide by 0.18m high (U.4). Unit 4 was only traced for 0.65m north of U.3. These two elements probably represent a bench (U.3) to which a wall foundation was later added (U.4) to subdivide whatever room(s) may have lain north of U.3.

Structure 1C-1-1st, therefore, is a 0.35-0.48m high stone-faced, earth-and-stone-filled platform built over an east-to-west rise in underlying S.1. The building encompasses 8.79m east-west (exclusive of the projections) and is aligned 6-12 degrees. The earthen-floored summit encompasses 5.63m east-west and may have contained a 0.43m high bench along with a raised work area on the east. The bench appears to have been backed on the north by at least two rooms divided by a low cobble foundation. No comparable enclosures were noted on the south. Limited summit clearing, restricted, largely, to a 1m wide (north-south) trench cut across the platform's approximate north-south axis, revealed very little of superstructure form, however.

All standing architecture, save for U.4, is built, primarily, of unmodified cobbles, principally limestone, set in a brown mud mortar. Some effort was made to orient the naturally flatter faces of these rocks outward. One masonry block was incorporated into U.3's south facing and schist slabs were occasional noted in U.2. Rock sizes range from 0.14x0.2m to 0.35x0.4m, the single cut block measuring 0.1x0.35x0.44m. Unit 4 is built with smaller cobbles (0.05x0.11m to 0.11x0.2m) that were not chosen for their naturally flat faces.

Time Span 3

Deposition of S.2 resumed after Str. 1C-1-1st's abandonment, eventually creating a layer that is at least 0.34m thick (the S.½ interface was not revealed). Stratum 3, a black (10YR-2/N),moderately fine-textured, hard-compacted, root-rich clay covers S.2 by 0.1-0.18m. A dense concentration of stones dislodged from final-phase architecture is embedded in S.3 and the upper portion of S.2, extending at least 1.14m east and west of construction (F.1). Feature 1 is also found above Str. 1C-1-1st's summit, denser on the west between U.2 and 3 than on the east between U.1 and 3.


The Central Depression (1 plan {1:100}, 2 sections {43E, 43F}; D95-78]

A series of 30 test pits, each measuring 1x1m, were dug along the summit of the depression's southeast side (Subop. 43E) and extending from that flank to the declivity's approximate center (Subop. 43F; 15 probes in each suboperation). Suboperations 43E and 43F are oriented 40 degrees, more-or-less parallel to the depression's southeast flank, and 130 degrees, respectively. Each suboperation measures 2m across, composed of two adjoining, parallel rows 1m wide and 15m long. A 1m gap was left between each excavated pit in these rows, two 1m2 tests in adjoining rows never being dug. Instead, the excavated pits alternate by row. The probes were carried down to maximum depths of 1.49m and 1.3m below modern ground surface in the declivity's center and on the southeast margin, respectively. The purpose of this work, overseen by C. Wells, was to determine whether the Central Depression was created by human action in antiquity, date that creation, and ascertain something of the declivity's original form.

Time Span 1

Stratum 1, a light beige, fine-textured, moderately hard-compacted clay with numerous small micaceous inclusions, was revealed only in the depression's center at 0.57-1.3m below current ground surface (Subop. 43F, Block 15). This earth level is at least 0.9m thick, its base lying beyond excavation limits, and appears to be culturally sterile. A similar layer was revealed at the base of excavations in the Southeast Depression (Subop. 43I, 43J, and 43K, S.1), though the latter stratum did contain some artifacts. A very few sherds diagnostic of the Middle Preclassic were recovered from later deposits within the Central Depression. They hint at an early occupation somewhere in the vicinity and may have derived from S.1, all other soils yielding much later materials. There is no direct confirmation of this association, however.

Time Span 2

Stratum 1, as revealed in Subop. 43F, Block 15, appears to have been cut into. The level descends rapidly, dropping as much as 0.73m over 0.9m south-to-north. The basin defined by this descent measures, over 1m across (its northern limits lying beyond our excavations) and is 0.43-0.73m deep (the eastern side may be lower than its western counterpart or we may simply have not dug far enough in the former direction to encounter the eastern margin). Erosion does not seem to have created or significantly affected the southern slope, given that this ascent is both steep and well-defined. In addition, ancient pottery sherds were found lying directly atop the ascent, indicating that the cut had been made in antiquity. It seems reasonable, therefore, to argue that the prehistoric inhabitants of La Sierra and/or its immediate environs dug out at least a portion of S.1, probably to obtain the micaceous clay that makes up this layer. Almost certainly, the pit identified in Subop. 43F, Block 15 was only a particularly deep probe dug near the center of the much larger excavation that created the Central Depression. Unfortunately, time constraints meant that Subops. 43E and 43F were not pursued to sufficient depths elsewhere to encounter S.1 and determine the extent of the original mining operation.

Time Span 3

Following cessation of digging, the Central Depression gradually filled in with soil and artifacts. Stratum 2, a brown (7.5YR-3/3), micaceous, fine-textured, moderately hard-compacted clay with small white inclusions, fills in the ancient pit. This earth level is as much as 1.08m thick where it overlies the lowest point in the basin cut into S.1. Stratum 2 was also exposed on the southeast margins of the Central Depression in Subop. 43E. Here, the level has an irregular upper surface (its base was not revealed), first rising 0.11m over 0.6m southwest-to-northeast, then running more-or-less level for an additional 1.1m in this direction, before dropping 0.17m and then 0.2m in two abrupt descents over the next 5.7m southwest-to northeast. Stratum 2 thereafter maintains a relatively even upper surface for another 6.3m; beyond this pont to the northeast, excavation was not pursued to sufficient depths to reveal S.2. Digging in Subop.43F also picked up S.2. Here, the layer ascends 0.28m in an unbroken slope for 4m from the depression's southeast margin towards the center. Stratum 2 abruptly ends at this point, only reappearing 11m further to the northwest in Block 15. The significance of the above-noted undulations is unclear (but see below). Given the clarity of the S.1 pit outlines, it appears that deposition of S.2 began soon after that excavation was abandoned.

Artifacts are generally sparse in S.2. The largest collection (46 sherds and 5 bajareque fragments) comes from within the S.1 pit. There are no clear signs that S.2 contained cultural material where it was exposed elsewhere in Subops. 43E and 43F.

Time Span 1

No clear soil distinctions were noted within S.1, this level consisting of a "pale yellow" (5Y-7/4), fine-textured, very loosely compacted ash throughout. Slight variations, based primarily on the nature of inclusions, were noted in the deep Block 3 probe into S.1. A 0.12m thick level marked by more carbon, white ash, and bajareque than noted elsewhere in S.1 was recorded at 1.18m below ground surface. A very similar entity, though with less bajareque extends up 0.15m from the excavation floor, its base lying beyond Block 3's limits. Approximately 0.3m separates these two components of S.1. Otherwise, there is no evidence for a break in S.1's depositional history nor does the nature of the trash change appreciably. Artifact densities in Subop. 43G blocks are uniformly high in all but the northwestern most pit (Block 2), ranging from 1,635-3,098 pieces per 1m3 (the Block 2 artifact density is 975 items per 1m3). Block 3 yielded comparable figures of 3,940 pieces per 1.75m3. Though artifact yields declined somewhat with depth, there was no clear sign that the bottom of the deposit lay close by. A total of 831 artifacts were recovered from the lowest 0.25m3 dug in Block 3. There was a tendency, however, to find diagnostics of older periods (in this case, Late Classic II ceramics) underlying those of later periods (Late Classic III) within S.1. This pattern may suggest, along with S.1's great depth, that the trash deposit was in use over a long interval (see also descriptions of S. 6 and 7 in Subop. 43I, Block B20 in the section dealing with the Southeast Depression).

Chronological Summary

Occupation in Op. 43 was probably initiated during the Middle Preclassic, evidence for habitation pertaining to this period being found near both the Southeastern and Central Depressions, though especially on the western and northeastern margin of the former. No architecture or other clear features are associated with this interval. The next signs we have of settlement in the area date to Late Classic I and, especially, Late Classic II. Material pertaining to these spans is found underlying construction throughout the investigated portion of Op. 43, usually associated with an ashy, artifact-rich soil. There are hints that certain relatively humble surface-level buildings were raised at this time (most likely in Late Classic II), especially Strs. 43-Sub1, 43-Sub2, and Str. 43-3-2nd. More impressive was the initial excavation of the Central and Southeast Depressions that seems to be attributable to these industrious La Sierrans. Whatever else they may been involved with, Late Classic I and II occupants of southern La Sierra were engaged in tasks that required considerable amounts of clay and generated large quantities of artifacts (especially pottery sherds) and ash. Late Classic III occupation is widespread throughout the Op. 43 zone and all excavated buildings, save those noted above, were erected now. Activities dating to this interval also generated their fair share of ash (as seen in Subop. 43G) and artifacts, especially concentrated within and around the Central Depression. Some portions of the latter declivity may have been dug at this time, though the excavations do not seem to have been as deep or extensive as those carried out in Late Classic I/II. Early Postclassic use of the Op. 43 area is suggested by the recovery of a few ceramics diagnostic of this period intermixed with Late Classic III materials. No free-standing constructions, or modifications to extant buildings, can be dated to the Early Postclassic. The paucity of such late remains implies that occupation throughout Op. 43 was sparse at this time. Late Postclassic markers are absent from analyzed collections while there is limited evidence indicating Historic occupation in the immediate environs of Str. AO-1st on the eastern margin of the Southeast Depression. No surviving Historic period architecture or other features were noted.