「衛星情報による古代エジプト遺跡の探査」

「衛星情報による古代エジプト遺跡の探査」
東海大学情報技術センター
惠多谷雅弘
発表要旨
エジプトの古環境と墓域構造理解に関する研究に地球観測衛星データを用
いたリモートセンシング手法を適用した結果、ナイル川西岸に位置する古都
メンフィスの葬送地域において、砂漠に埋もれた古代エジプト遺跡を発見し
た。現在までの発掘結果から、発見された遺跡はエジプト新王国時代後期（紀
元前1400年∼1300年頃）に属するトゥーム・チャペル（Tomb Chapel：ピラ
ミッド付の神殿型貴族墓）を中心とする壮大な墓域であることがわかった。
古代エジプトを対象として、衛星データによって砂に埋もれた遺跡を検出
し、考古学的検証により確認されたのは本例がエジプト学史上初めてであり、
本研究はエジプトの砂漠地帯における遺跡調査にリモートセンシングが極め
て有効であることを実証した。
資
A study for the pyramid exploration utilizing satellite data analysis and
the discovery of ancient Egyptian remains at Dahshur North
M. Etaya*, T. Sakata*, S. Yoshimura**, J. Kondo**, S. Hasegawa**
ABSTRACT
By the new archaeological observation method utilizing satellite data, an
extensive cemetery with a mud brick construction supposed to be a tomb-chapel (shrine
type tomb for nobles) of the New Kingdom period was discovered in the desert area of
the Nile west bank, Egypt.
using this new method.
It was the first discovery in the history of Egyptology
The site was pinpointed by the satellite data analysis in the
first phase of the pyramid exploration.
In this paper, the method and process
producing the discovery are described.
1. Introduction
The pyramids which represent funeral complexes of ancient Egypt were built in
the desert area of the Nile west bank between the Old Kingdom period and the Middle
Kingdom period.
Studying pyramids is one of the important subjects in Egyptology.
However there are a lot of riddles on the pyramids and even the purpose of
construction if it is king's tomb or not is still uncertain.
On the other hand, it is
reasonable to suppose that there still remain undiscovered pyramids in this area,
because there are at least three kings such as Menkauhor (5th dynasty), Neferkare
(7-8th dynasty), and Ity (9-10 dynasty) whose pyramids are missing although there is a
possibility of the pyramid building.
If we can find their pyramids in the original state,
the purpose of construction and many other unsolved riddles on the pyramids could be
revealed.
Tokai University Research & Information Center (TRIC) has carried out
archaeological observations using satellite data in various places of the world.
The
method is called "SPACE ARCHAEOLOGY", which investigates remains and
paleoenvironment from space.
Here it was intended to be used in Egyptology.
A
study for the pyramid exploration using satellite data has been carried out in
cooperation with the Egyptian Cultural Center of Waseda University since 1994.
*Tokai University Research & Information Center
**The Egyptian Culture Center of Waseda University
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料
2. The exploration target
The study area is the desert of the
Nile west bank from Abu Rawash to
Maidum known as pyramid zone. In this
study, the point we must consider is
whether there still remain undiscovered
pyramids with the original form like the
three Giza pyramids.
Kufu's pyramid of
Giza, usually called Great Pyramid, which
was built in the Old Kingdom period must
be one of the most famous monuments in
the world.
Fig.1
The target area
The scale size of Kufu's
pyramid is approximately 230m in base
length and the height is 146m.
However,
it is hard to consider that such a huge complex with the original form was buried under
the desert and has been undiscovered so far.
The pyramid was almost certainly
robbed of its original contents during the period of political instability and social unrest
which followed the weakening of the central royal power after the end of the Old
Kingdom.
In fact, collapsed or unfinished pyramids which became like a rubble
mountain or a site with only the foundation and without the upper part like the
pyramids of Sekhemkhet or Pepy I at Saqqara were prominent.
Consequently, we
focused on these collapsed or unfinished pyramids as the main exploration target in
this study.
3. Satellite data analysis
Optical satellite data and microwave satellite data were used to detect the trace
suspected to be collapsed (or unfinished) pyramid or artificial objects.
A L band
microwave image of JERS-1/SAR (Synthetic aperture Radar) and C band microwave
images of EERS-1/SAR were analyzed to find the microwave signature of cemetery's
bedrock, limestone blocks, mud bricks, and some other archaeological objects such as
pottery shards and stone fragments.
Optical satellite data of SPOT Panchromatic,
Landsat-TM and KVR-1000 were intensively analyzed to clarify the shape and other
characteristics of existing remains, especially focusing on some collapsed or unfinished
pyramid bases, ranging from Abu Rawash to Mazghuna.
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Landsat/TM
(87/FEB/08)
JERS-1/SAR
EERS-1/SAR
KVR-1000
(94/AUG/26)
(94/NOV/12)
(91/FEB/27)
Fig.2 Examples of satellite images used in this study
In SAR image, the density of the image is in proportion to the backscatter
strength of microwave.
Strong backscatter was mostly indicated in SAR image
around artificial constructions including pyramids and ancient monuments.
While C
band SAR at a frequency of 5.3GHz of EERS-1 properly showed surface undulation of
the desert such as wadi and hilltop, L band SAR image at a frequency of 1.275GHz of
JERS-1 detected the artificial constructions in the desert area more clearly.
As for L
band microwave, it has been already proved by the SIR-C (Shuttle Imaging Radar C)
examination of NASA that it penetrates into sand layer in very dried desert area.
Namely, artificial objects buried underground including pyramids and ancient
monuments could be found, though invisible to optical sensor, if it is possible to detect
their particular radar backscatter in the desert area where nothing should exist.
For
this reason, we tried to detect the artificial objects using JERS-1/SAR image.
Optical satellite images were used to clarify the shapes of existing collapsed or
unfinished pyramids and their formation. To begin with, spectral characteristics for
the pyramid complex and similar scale limestone monuments in Landsat-TM image
were examined.
Next, verification of the necessary ground resolution for these
constructions was made by SPOT image.
It were turned out that strong spectral
reflections differing from the surrounding sands were detected around the pyramid
complex and similar scale limestone monuments, and a 10m ground resolution is
sufficient to identify the pyramid complex and similar scale limestone monuments.
A
2m resolution image of KVR-1000 was used for understanding the surface shapes of
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collapsed or unfinished pyramids.
The shapes of collapsed or unfinished pyramids are
peculiar, and may be categorized into 8 types.
As a result of the satellite data analysis, 38 noteworthy points supposed to be
traces of unknown artificial constructions were detected in the target area.
Repeated
ground truths based on the result of satellite data analysis were carried out, and it was
proved that some points of them were obviously remains of the dynastic period which
have been not yet reported, though they were mostly inside other's concession area or
military controlled area.
a
b
c
d
e
f
1. Ra'djedef (4th Dyn.: Abu Rawash)
5. Senwoseret III (12th Dyn.: Dahshur)
2. Ra'neferef (5th Dyn.: Abusir)
6. Amenemhet II (12th Dyn.: Dahshur)
3. Pepy I, Merenre (6th Dyn: Saqqara)
7. Amenyqemau (13th Dyn.: Dahshur)
4. Kendjer, Unknown (13th Dyn.: Saqqara) 8. Unknown (12-13th Dyn.: Mazghuna)
Fig.3
Collapsed (or unfinished) pyramids in KVR-1000 image and the categorized types
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4. Simulation of the dynastic waterfront in the Memphite necropolis
It is also important to reveal the dynastic environment of the Nile basin, because
its necropolis formation could be determined by reconstruction of the dynastic
waterfront with the funeral complex.
from summer to autumn.
In ancient time, the Nile overflowed regularly
For this reason, the pyramids were usually built on a
hilltop of the desert area which was not flooded.
Digital Elevation Model (DEM) of the
target area was made using topographic maps in the scale of 1:5,000, and the water
level of the Nile in the dynastic period was simulated.
The resulting image shows that
the pyramids and funeral complexes in the period of the Old Kingdom and the Middle
Kingdom are mostly located on bedrock higher than 40m above sea level which was not
flooded.
5. Determination of the excavation site
Ground truths verified that at least 4 points (i.e., Site No.=26, 27, 29, 35) were
obviously remains of the dynastic period. At the sites of No.26 and 27 close to the
pyramid of Kendjer, though we knew afterward that they were already unearthed,
many surface deposits such as limestone fragments and artificial objects including 3
stone coffins have been observed. As for the site of No.29, it was obviously remains
characterized in the New Kingdom period which was not yet reported.
The site was
almost flat desert, however strong backscatter estimated to be caused by mud brick
architecture covered with thin sand or many surface deposits such as limestone
fragments, and pottery shards was detected in L band SAR image of JERS-1.
It was
quite worth discovery, because there was no example that unknown remains were
detected by SAR data in Egypt.
However the site was ignored in this study, since it
was thought that no pyramid was built in the New Kingdom period.
Consequently, the site of No.35, which is located approximately 30km south of
Cairo, 2km north-east of Snefru's Red pyramid, was determined as our excavation site.
The reasons were as follows;
a)
The high resolution optical satellite image of KVR-1000 clearly showed that
there were three circular hollows standing in diagonal line similar to the
pyramid formation of Giza.
b)
The circular hollow mostly can be seen in the center of collapsed or unfinished
pyramids, and the site was surrounded by the Old and the Middle Kingdom
monuments such as Snefru's Red pyramid and the pyramids of Senwoseret III.
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c)
Strong spectral reflection which is usually detected around the pyramid or
limestone construction was shown in Landsat-TM and SPOT images.
d)
The height was 47-50m which meets the result of the water level simulation of
the dynastic period that most pyramids or funeral complexes are located on
bedrock higher than 40m above sea level.
e)
A total of 15 shafts disturbed already and more than 150 surface deposits (i.e.,
fragments of stone blocks with reliefs and inscriptions, pottery shards, shabtis,
rings) were found in the ground truths.
6. Discovery
The site was named "Dahshur North". It was indicated on Lepsius's map, but
nothing was reported about the remains.
investigation in March, 1996.
The excavation began with preliminary
The most conspicuous discovery was a mud brick
construction, which was supposed to be a typical tomb-chapel of the New Kingdom
period with the scale of 47m in length and it was comparable with the largest example
of Horemheb at Saqqara.
The construction was unearthed on the central hilltop of the
site where the soft limestone chips were dense on the surface.
The upper part was
mostly lost, however the general plan was divided into the ramp, courts, chapel with
side rooms beside it.
Although it was not pyramid complex of the Old Kingdom and
the Middle Kingdom period, a limestone pyramidion (cap stone) about 60cm in the
height considered to be placed at the top of the tomb-chapel was also unearthed.
The shaft and the several underground chambers were revealed in the center of
the second court.
The shaft entrance was found 4m below the surface and it was
elaborately lined with the limestone blocks.
Two doorways to seven underground
chambers appeared at the bottom where it measured approximately 13m from the floor
level of the court.
In the latest excavation, an innermost underground chamber with a
huge granite sarcophagus was additionally found.
In consequence, a great number of relics exceeding 4,000 have been found so far.
Total assemblage of the finds suggested the period of the late 18th dynasty or the early
19th Dynasty, because some specific royal names (i.e., Akhenaten, Tutankhamun, his
wife Ankhesenamun, Ramessess II) were recognized from some objects.
Considering
the scale size of the tomb-chapel remains and elaborate construction of the shaft, the
owner must have been a high official connected to the royal family.
Anyhow the
excavation result is completely new in the Memphite topography because the New
Kingdom monuments had not been reported in Dahshur area.
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Water front of the Nile
at a water level of 40m
(○: pyramid)
Shadow image processed by DEM
Fig.4
The water level simulation
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(Left: JERS-1/SAR image, Right: The general view of the site No.29)
Fig.5
The remains at the site of No.29 discovered by SAR
( Enlargement of the site No.35)
Fig.6
KVR-1000 image around the sites of No.26, No.27 and No.35
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Fig.7
The general view of the site No.35 before excavation
Limestone fragments carved in hieroglyph
Fig.8
Examples of the surface deposits at the site No.35
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Fig.9
The discovered tomb-chapel
Fig.10
Plan of the tomb-chapel
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Fig.11
Pyramidion
Fig.12
Shaft A
The lid
Sarcophagus
Fig.13
The Goddess of Isis and inscriptions
The granite sarcophagus found in the innermost chamber of the tomb-chapel
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Fig.14 A group of beads (Necklace)
Fig.16
Faience ring of Tutankhamun
Relief
Fig.15
Jar sealing with the name of
Tutankhamun
Fig.17
Faience ring of Ankhesenamun
Stela
Fig.18
Some other examples of finds
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Shabti
7. Conclusion
A method of Space Archaeology was used on pyramid exploration studies, and
some remains including the site of Dahshur North have been detected and found to be
important for necropolis formation and environmental studies in a very short time.
In
this study, a total of 10 scenes of satellite data were comprehensively analyzed with the
aid of DEM data and archaeological examination data.
It is the first example in the
history of Egyptology that the site was specified by the satellite data analysis and a
successful excavation followed.
The discovery proves that satellite data is useful in
archaeological observation in the desert area as well as being a clue for the pyramid
exploration in the next stage.
References
1)
Sakata, Etaya, Yoshimura, Kondo, Hasegawa, Tsuboi, "A study for pyramids
exploration by using satellite data and the discovery of the ancient Egyptian
remains", Journal of the Japan Society of Photogrammetry and Remote Sensing,
vol.36, No.6, 1997, 41-53
2)
Yoshimura, Kondo, Hasegawa, Sakata,
Etaya, Nakagawa, Nishimoto, "A
preliminary report of the general survey at Dahshur North, Egypt", Annual report
of the collegium Mediterranistarum, 1997, 3-8
3)
Yoshimura, Kondo, Hasegawa, Nakagawa, Nishimoto, Kashiwagi, Sakata, Etaya,
"Preliminary report of excavations at Dahshur North", Annual report of the
collegium Mediterranistarum, 1998, 4-24
Satellite image
KVR-1000 : ©TRIC/Sovinformsputnik, 1999
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