The Mallakastra Regional Archaeological Project
Geosciences 2002
M. E. Timpson and S. B. Yazvenko
The geoscience program
for 2002 had two primary goals: 1) to follow-up on palynological investigations
initiated in 1999 and 2000, and 2) to integrate soil and geological observations
with the archaeological survey program in the Margelliç area. Additional
activities that developed through the course of the field work included the
initiation of a lithic source study of the volcanic mill stones recovered
from a variety of site locations over the course of the project and site-specific
soil/geological observations at a number of sites that were the object of
archaeological
site-collection activities.
Palynological Research
Palynological research focused on three areas that were initially examined
in 1999 and 2000. The object of this year’s work was to recover cores
from sites closer to Apollonia than the lagoon at Nartë (where an 11 m. deep
core had been taken in 2000), and to ensure that critical developmental periods
in the history of the area of Apollonia were covered by cores: in particular,
the time of the foundation of the Greek colony, the transition from Greek to
Roman rule, and the period of the Ottoman conquest. New cores were collected
from the former marsh at Mbrostar, the extant wetland complex at Roskovec,
and the small lagoon at Kërrnicë, west of Povelc, near the shore of the Adriatic. Test
coring at Mbrostar and Roskovec in 2000 yielded promising dates and sufficient
pollen concentrations to warrant further study, provided an appropriate coring
device could be utilized. A core collected from Kërrnicë in 1999 demonstrated
that deposition in this area had been extremely rapid over the last 500 years. We
returned this year with a Hiller coring device that facilitated the collection
of vertically intact cores in the heavy-textured, partially drained sediments
at Mbrostar and the floating peat and lacustrine sediment sequence at Roskovec.
Mbrostar
The former wetland complex at Mbrostar has been drained for agriculture by
a series of open ditches up to 1.5 m deep. Due to the effects of drainage,
we used a Dutch soil auger to core approximately 1.3 meters below the base
of one of the larger drainage canals before collecting any pollen samples. Sediments
below this depth did not appear to be influenced by oxidation resulting from
drainage activities. We collected a 3-meter-long core (extending from
2.75 to 5.75 m below the current land surface) from a location approximately
1 kilometer east of the location that was sampled in 2000. A number of
zones in this year’s core contained well-preserved plant remains that were
sampled for
14C dating. The lower portion of the core will
be dated using bulk sediment samples due to the lack of visible plant remains. Test
coring conducted in 2000 yielded a
14C date of about 2000 BP (uncalibrated)
from a sample about 3 meters below the present land surface. Since the
core collected this year begins at about the same depth, we expect the new
core to yield data covering a portion of the late Holocene (ca. 2000 - 4000
BP, based on the sedimentation rate determined from the 2000 core). Although
we will not have any data covering the last 2000 radiocarbon years, the core
will allow us to correlate local variation in vegetation communities with the
same time period in the Nartë core (which should provide a regional picture
of paleoecological conditions). The core will also provide a “snap-shot” of
the ecology of the Seman River floodplain during this period, adding to the
information already provided by Eric Fouache’s research (Fouache et al., 2001).
Roskovec Test
cores from Roskovec collected in 2000 yielded stratigraphically correct dates
of 1425 AD cal. (at 2.5 m below the surface) and 105 AD cal. (at 3.6 m below
the surface). Based on these dates, it was apparent that further coring
in this location, with the right equipment, could yield a picture of the paleoenvironment
over a relatively long period of human occupation in the vicinity of Margelliç. The
local record from the core at Roskovec, like the core at Mbrostar, can also
be correlated with the regional record from Nartë. The wetland at Roskovec
consists of a floating mat of peat overlying a sequence of clay-rich lake deposits. The
4.3-meter-long core retrieved in 2002 was located within a meter of one of
the test cores collected in 2000. Pollen and
14C samples were
collected from the lower part of the peat mat and throughout the sequence of
clayey lake deposits. Several high-quality organic materials were sampled
for
14C dating, including two mineral-peat-mineral sequences, indicating
that the lake dried up and became a marsh (like it is today) at least twice
during the time period covered by the core. These environmental changes
may be related to paleoclimate or anthropogenic effects, but at this early
stage of analysis these are only hypotheses.
Kërrnicë
In 1999, a 4 to5 meter-long core was recovered from the lagoon at Kërrnicë. Carbon
dating of sediment from the base of this core yielded a date of 1445 to 1645
AD (calibrated). This date range covers at least a portion of the Ottoman
period in the Apollonia area. Based on this result, and the fact that
the 1999 core has deteriorated in storage, we decided to collect an additional
core from Kërrnicë. Initial coring was begun on the west side of the
island located at the northern end of the lagoon, in close proximity to the
core collected in 1999. The first meter of this core consisted of very
sandy mud deposits, that are not favorable for pollen preservation. The
core terminated at about 1.8 meters on a relatively dense sand layer. We
abandoned this core and began probing the lagoon for a more suitable core location. Extensive
test probing indicated that the sand layer that terminated core 1 was rather
continuous throughout the lagoon at a depth of 1.8 to 2.5 meters. Based
on this information, we chose a second core location approximately 15 meters
off the southern tip of the island in 1.5 to 1.7 meters of water. We
recovered a 2.5 meter-long core from this location. The sediments consisted
of dark gray, reduced estuarine muds (silty clays). Plant remains collected
for dating should yield reliable
14C dates for much of the length
of the core. The bottom date will be based on a bulk sediment sample
due to the lack of visible plant remains. Although the 2002 core from
Kërrnicë is only about half as long as the core collected in 1999, it is possible
it may represent the same time interval as the 1999 core due to the highly
variable nature of sedimentation in the Kërrnicë area. Rapid and variable
sedimentation conditions in the Kërrnicë area could result in very low pollen
densities, thereby reducing the reliability of the analyses. If pollen
densities are too low, palynological analysis of the core may prove useless. Additional
paleoecological data can be recovered from this core through the analysis of
the diatom remains. Diatoms are microscopic zooplankton whose skeletons
are composed largely of silica. These organisms live in marine, brackish,
and freshwater environments and are excellent indicators of water chemistry
and aquatic environment. If the pollen yield from samples collected at
Kërrnicë is too low for reliable palynological analysis, it would be more useful
to examine the diatom record. If both records can be investigated, a
clearer interpretation of the paleoenvironment of the lagoon would result. With
the completion of fieldwork in 2002 we feel reasonably confident that we will
have at our disposal pollen analyses for the Neolithic and later periods from
Nartë, and for the past two millennia or more from the cores taken this year
from locations closer to the site of Apollonia
.
Soils and Geology Near Margelliç
Figure 1
The archaeological survey area surrounding Margelliç is underlain
by sedimentary rocks dating to the Pliocene and Miocene. These rocks
were deposited at a coastal margin in near-shore and offshore environments. The
village of Rusinja is underlain by an upper Miocene deposit that consists
of mudstones,
sandstones, and gypsum deposits [Figure 1]. The
first area surveyed by Teams M and L is separated by a geologic contact between
this Miocene deposit and an unnamed Pliocene deposit that underlies a part
of the citadel of Margelliç. The contact between these two geologic
units continues northward and extends to the large reservoir north of the
village
of Kuqari. The main village of Kuqari is underlain by rocks of the
Rrogozhina Suite, an upper Pliocene deposit consisting of conglomerates,
sandstones, marls,
and calcareous mudstones, and straddles the contact between the Rrogozhina
Suite and the unnamed Pliocene deposit mentioned above. The village
of Margelliç is underlain by Rrogozhina Suite rocks and is located
close to the contact between the Rrogozhina and the unnamed Pliocene deposit. The
citadel at Margelliç straddles two Pliocene deposits, the unnamed
unit that appears to consist largely of marls and fine-grained sandstones
(based on personal
observations of road cuts), and the Rrogozhina Suite. The Rrogozhina
Suite is the same group of sediments that underlie the Apollonia survey area. The
village of Patosi (Mustafa Matohiti) is underlain by the unnamed Pliocene
deposit. These
rocks extend westward to just east of the village of Rrërësi where
the deposits transition back to the Rrogozhina Suite. Southwest of
Rrërësi, the Rrogozhina
Suite transitions to an older Pliocene formation, the Helmesi Suite. This
formation is composed of mudstones, siltstones, and sandstones. Two days
were spent walking with the archaeological survey teams in areas north and
west
of the villages of Margelliç and Patosi (Mustafa Matohiti) to assess
the soils and landforms in that part of the survey area. The initial
survey area around Rusinja was not examined this year due to scheduling conflicts.
The
ridges and valleys below Patosi (Mustafa Matohiti), covered by Team M, consist
of soils formed in residual bedrock of the unnamed Pliocene formation and
alluvial fill material deposited in the larger stream valleys [Figure2].
Figure 2
The soils on the ridge tops and side slopes are moderately
eroded, with most agricultural activities occurring on red-colored B-horizons. Footslopes
and valley bottoms have received significant quantities of sediment from higher
lying areas. Artifact distributions in this area have been impacted by
both erosional and depositional processes. Smaller artifacts are likely
to have been transported down slope and buried by subsequent depositional events,
whereas larger artifacts may be left behind on ridgetops as an erosional lag. Careful
interpretation of the artifact distributions in this area is required, because
even small concentrations in upland areas may be significant. Given the
degree of deposition in the valleys, surface survey is unlikely to identify
much evidence of past occupation in these locations (see the archaeological
report for the results of survey in this area). The highly dissected ridges
north of Margelliç, surveyed by Team L, are underlain by Pliocene Rrogozhina
Suite rocks. This area was once covered by thick, Terra Rossa soils,
as evidenced by scattered remnants on ridge tops and side slopes [Figure 3].
Figure 3
Soils and geology in this area are similar to the Terra
Rossa soils surrounding Apollonia. The majority of Terra Rossa soils
formed in coarser-textured deposits (sandy and gravelly sediments) that contained
abundant crystalline limestone fragments (as at Kryegjata B and the quarry
at Radostina). Road construction for early oil field development has
resulted in accelerated erosion that has denuded large portions of this survey
area [Figure 4].
Figure 4
A few, isolated
patches of intact soil (A-horizons were 15 to 20 cm thick) were noted in
this area, but most soils were truncated, with modern vegetation growing
directly
in eroded B-horizons [Figure 5].
Figure 5
Erosion and deposition have
influenced the distribution of artifacts in this area too. Erosion
of the ridge tops has transported artifacts down slope, but it has also led
to
deposition of significant (0.6 - 1 m) amounts of red soils on lower lying,
shoulder and backslope positions, thereby masking artifacts in these locations
[Figure 6].
Figure 6
So, there are two
geomorphic factors affecting artifact distributions in this part of the
Margelliç survey
area; loss of soil from the ridetops, carrying artifacts down slope, and
deposition of eroded sediment in lower relief portions of shoulder and
backslope areas
masking in situ artifacts in these locations. These observations
are consistent with survey results presented in the archaeological report.
Mill Stone Analyses
In an effort to determine the probable source of the volcanically-derived mill
stones recovered from a number of sites over the last 4 survey seasons, we
initiated a small museum study this year (see the archaeological report for
artifact details). The stones were likely imported to the Apollonia area,
because no volcanic formations occur in the Malakastra region. The mill
stones could have been imported from the Italian mainland, Sicily, or possibly
Greece. Samples were collected from each of the highly vesicular, volcanic
mill stones for mineralogical, petrographic, and geochemical analyses at the
University of Cincinnati. The geochemistry and mineralogy of the Italian
volcanic regions have been widely documented, and Runnels (1990) has documented
mill stones from the Aegean, so we should be able to identify the likely source
of these artifacts.
Archaeological Site Collection
Additional soil and geological observations were made at four locations where
site collections were made by the archaeological teams. These included
Site 35, an Ottoman period site in the Peshtan Valley; Site 40, a Hellenistic
period site on a ridge top south of Shtyllas and northwest of Site 34; Site
39, a concentration of Paleolithic artifacts near Kraps; and Site 26, a Hellenistic
period site on the ridgetop above the village of Shtyllas. Site 35 is located
toward the nose of a spur ridge running westward from the spine of the Cakran
ridge. It is underlain by bedrock of the Pliocene Rrogozhina Formation. The
soils are remnant Terra Rossa formed in medium-textured (gravelly sands and
silts) sediments. The area that was surface collected has been subject
to slight to moderate erosion. The flatter portions of the ridgetop have
only lost a small amount of the original soil, whereas the more sloping shoulder
and backslopes have likely lost all of the original A-horizon and some portion
of the upper B-horizon. The existing soils are intensively cultivated,
so artifact distributions and densities have likely been affected by plowing. Site
40 is located on a highly eroded ridgetop and side slope underlain by fine-grained
sandstones of the Rrogozhina Formation. Cementation of the sandstones
is highly variable, ranging from barley cemented to highly consolidated. The
more weakly cemented rocks and the soils formed from them are susceptible to
erosion from water and wind. The site area has been heavily overgrazed,
further exposing the soil to erosive processes. It is likely that much
of the site has been washed down slope to the west. Site 39 occupies a high,
strath terrace of the Gjanice River and the adjoining spur that trends northeast
southwest from a higher lying north-south trending ridge. The terrace
is underlain by Miocene-aged rocks consisting of sandstones, mudstones, and
siltstones. The high ridge to the east of the site consists of Pliocene-aged
Helmesi Suite rocks of similar composition. The present land owner told
us that a portion of the terrace had been excavated for fill to create the
dam for the reservoir that is located just south of the site. It is impossible
to say how much of the original terrace surface may have been removed for this
purpose. He also informed us that he plows the fields that span the terrace
and the spur ridge to a depth of 30 cm twice a year with a tractor. It
seems unlikely that artifacts recovered from the western-most portions of the
site are
in situ. Analysis of the site collection data will need
to account for the disturbances noted above. Site 26 is located on a
ridgetop above the village of Shtyllas. The ridge is capped by a gravel
and cobble conglomerate of the Pliocene-aged Rrogozhina Suite. The slopes
below the summit are underlain by fine-grained sandstones and marly siltstones
of the same formation. The summit has been disturbed by construction
of a water tower and military bunker complex. The slopes are covered
by 50 to 100 year old olive trees that are interspersed in a matrix of
low-growing herbaceous vegetation both of which serve to stabilize the current
landscape. Erosion of the summit and side slopes is generally moderate,
although some high traffic areas have been seriously disturbed. Interpretation
of the site collection data should include the effects of landscape position
and erosion. References Cited Fouache, E., G. Grunda, S. Mucaj, and P. Nikolli.
2001. Recent geomorphological evolution of the deltas of the Rivers Seman and
Vjosa, Albania. Earth Surf. Proc. and Landforms 26:793-802. Runnels, C. 1990.
Rotary querns in Greece. Journal of Roman Archaeology 3:148-153.