The Iranian-Italian Joint Expedition in Khuzistan started work in the area of Hung-e Azhdar, a small village located at the entrance of a valley in the Bakthiari Plateau, about 17 km north of the modern city of Izeh.
This project has been developed within the framework of a Memorandum of Understanding, signed between the Iranian Center for Archaeological Research (ICAR) of the Cultural Heritage, Common Handicrafts and Tourism Organization of the Islamic Republic of Iran (ICHTO) and the Centro Ricerche Archeologiche e Scavi di Torino per il Medio Oriente e l’Asia (CST). Other institutions involved in the project, as partners of the CST, were the Dipartimento di Ingegneria del Territorio, dell’Ambiente e delle Geotecnologie del Politecnico di Torino (DITAG), and the Dipartimento di Scienze Antropologiche, Archeologiche e Storico-Territoriali dell’Università di Torino (SAAST).
The Expedition is financed by the Fondazione CRT of Turin and the Ministry of Foreign Affairs of the Italian Republic .
Laser scanning of the Hung-e Azdhar rock relief and preliminary survey of the surrounding area (March 4 - 12, 2008).
The aim of the Expedition was the acquisition by laser scanning of a Parthian rock relief, depicting a scene of homage or investiture (?), and carved on the surface of a large boulder close to the southern slopes of the valley. This relief is is about 5.40 m long and 2.10 m high, while its lower edge is about 1.50 m from the soil. The sculpted surface covers about 11 m2 and ranges from about 1 to 15 cm in depth. The sculpted scene shows a bearded horseman followed by an attendant and four standing men. This rock relief is of special interest within the art of ancient Elymais, since the iconography and the style of the figures in the scene are very different: whilst the four standing men in the right half of the relief are depicted in a frontal position and in Iranian dress, the horseman and his attendant in the left half are the only figures among the whole set of Parthian rock reliefs to be depicted in profile. Because of these contradictions, the chronology and the interpretation of the scene are still under discussion and completely change the historical framework of the sculpture and of the commission of the relief: some scholars refer the execution of the horseman and his attendant to the conquest of Elymais made by Mithradates I in 140-139 BC, or rather in the following decades; others refer the standing figures to a production –or to an addition (?)– at the request of a local ruler of the 2nd-3rd century AD. The Hung-e Azhdar rock relief has been already surveyed with traditional methods in the past years. These researches provided a number of photographs and drawings which, even when of high quality, do not allow for a more in-depth examination. For this reason, the present project aimed to increase information by the use of a laser scanner.
This technology can allow to conduct a detailed examination of the sculpted surface and a precise measurement of the carving’s depth in different points of the scene, and so shed new light on the carving techniques of all the represented figures. The erosion of the surface could also be detected, updating the acquired information with further periodic scanning, in order to make comparison with previous data. The sculpted surface of the boulder has been divided into 34 squared sectors, each of 60x60 cm. About 15,000 markers were placed on the surface, at a distance of no more than 5 cm one from the other, in order to allow the scanner to recognize its position in a 3D model. Each sector has been separately scanned with a high definition handyscan 3D (model HZ), perpendicularly moved at about 15-20 cm from the rock surface: 34 frames have been acquired as digital files at the highest resolution (1,95 mm), and an overlap band has been saved between adjacent sectors, with a 10% tolerance.
The scanner never touched the surface during operation. Images with a pthotogrammetric digital camera (model Kodak DCS PRO 14m) have also been acquired in order to update the information provided by the laser scanning: 22 frames have been photographed twice, at a distance of 5,3 and 1,3 m (for details). Vertices have been located on the ground by a GPS receiver (model Topcon Hiper PRO) and by traditional topographic method, while 70 ground control points, placed on the sculpted surface, have been located by a total station (model Topcon Get 3005N), in order to define a network for further topographic surveys. This allowed to relate the numerical and tridimensional nature of the acquired information to a known reference system.
The acquired frames have been merged and elaborated in the laboratory of the DITAG, and allowed to create a 3D digital model of the rock relief consisting in 7.692.104 points, with an accuracy of 0.2 mm approximately. The images acquired by the digital photogrammetric camera have been elaborated to obtain a digital orthophoto and “Solid Images” of the scanned surface. Solid Images are digital images where all pixels contain x, y and z coordinates, providing information in a known reference system, so that it is possible to measure angles, distances and areas. These are high resolution RGB files (non orthorectified), integrated by a numerical matrix of the same resolution, containing tridimensional data of the scanned surface.
A specific software (SirIO) has been created for the analysis of these data. This software allows to manage all the elaborated files –the 3D model, the orthophoto and solid images– on a unique digital platform: traces of tools on the sculpted surface, differences in the depth of the carving, and the natural conformation of the rock have to be examined in order to verify whether in the two halves of the sculpted scene, besides the evident contradictions in iconography and style, there are also differences in the carving technique and evidence of re-sculpting. Because of the lack of no detailed surveys in the Hung-e Azhdar valley, a preliminary archaeological survey of the surrounding area was also planned, with the purpose of discovering traces of further archaeological remains. A small area of about 4.400 m2, very close to the boulder carrying the reliefs, has been surveyed, revealing the presence of pottery, broken in sherds, and very few fragments of bones, gathered with rubble in small groups of different size. These groups surround the boulder in all direction: they have irregular shape and seem to belong to a disturbed archaeological context. At least 19 small groups of sherds and rubble have been recognized.
Laser scanning of the Hung-e Azdhar, Hung-e Yaralivand, Hung-e Kamalvand rock reliefs, topography of the valley of Hung-e Azhdar and trial trenches near the boulder of Hung-e Azhdar
(February 9 - March 2, 2009)
The Iranian-Italian Joint Expedition in Khuzistan started the 2nd campaign in the area of Hung-e Azhdar, in order to develop the research begun in the 1st campaign (2008).
Members of the Expedition were Mr. Jafar Mehrkian (ICAR, archaeologist and co-director), Mrs. Yalda Sourani (ICAR, architect), Mr. Mehdi Faragi (ICAR, archaeologist), Mr. Neamatollah Salashoor (archaeologist), Mr. Mojtaba Shokrollahi (photographer) and Mr. Ali Reza Ismaili (technician), for the Iranian side, Mr. Vito Messina (CST, archaeologist and co-director), Mr. Paolo Ardissone (DITAG, archaeologist and topographer), and Mrs. Cristina Bonfanti (DITAG, architect), for the Italian side. Supervisor of CST was Prof. Antonio Invernizzi. Supervisor of the DITAG was Prof. Fulvio Rinaudo.
The aims of the Expedition were:
– the acquisition by laser scanner of the natural surface of the Hung-e Azhdar rock relief and of the sculpted surface of the Hung-e Yaralivand and Hung-e Kavalvand rock reliefs;
– the topography of the valley of Hung-e Azhdar;
– the opening of trial trenches near the sculpted boulder of Hung-e Azhdar.
1. Laser scanning of the Hung-e Azhdar, Hung-e Yaralivand, Hung-e Kamalvand rock reliefs
1a. Previous situation
The preliminary survey of the Hung-e Azhdar, Hung-e Yaralivand and Hung-e Kamalvand rock reliefs revealed the presence of targets for photogrammetry on the rock surface of all the sculpted reliefs. These are rectangular targets made of paper that have been fixed to the rock surface by a strong glue.
These operations do not pertain to the present project and the relevant targets have been previously fixed on the rock. The presence of these targets has been reported to local Authorities by the Iranian co-director before starting our operations. During the preliminary survey of the Hung-e Azhdar rock relief clear traces of rainwater erosion have been detected on the surface: these are originated particularly by a long crack on the upper part of the boulder, that works as a natural pipe for the water flowing from the top of the boulder when it rains.
1b. Laser scanning
Acquisition by laser scanner lasted 4 days. The natural surface framing the sculpted relief of Hung-e Azhdar has been scanned with a resolution of about 1 mm. The acquired surface will be merged with the information provided by laser scanning of the sculpted surface, completed during the 1st campaign, in order to upgrade the 3D digital model of the boulder.
The rock relief of Hung-e Yaralivand depicts two standing men in frontal position, each dressed in a tunic with trousers. The lower part of each tunic is bell-shaped and the feet of the figures are turned in profile. The right figure has his left hand at his hip, while the left figure has his right to his hip. This relief is interpreted as a scene of investiture where the right man is investing a prince with his authority (Mathiesen, 1992, 123-124).
The sculpted surface of the rock relief of Hung-e Yaralivand has been divided into 9 squared sectors, each of about 60x60 cm. Markers were placed on the surface in order to allow the scanner to recognize its position in a 3D
model. These markers are circular spots with a diameter of about 5 mm that have been completely removed after acquisition. Each sector has been separately scanned with a high definition handyscan (model HZ), a self-positioned hand-held scanner, perpendicularly moved at about 15-20 cm from the rock surface. The scanner never touched the surface during operation.
The rock relief of Hung-e Kamalvand has been acquired with the same technique and the sculpted surface has been divided into 9 square sectors each of about 50x50 cm. It depicts a standing figure wearing a long belted robe and facing a horseman proceeding to right. An Elymaean inscription runs on the upper part of the scene: “Phrates the priest, son of Kabnuskir” (Hinz, 1963, 171). It is generally assumed that this inscription refers to the horseman (Kawami, 1987, 72-73) and claims to a royal descent, while the standing figure remains unidentified. But it is possible that the inscription
refers to the standing figure rather then to the horseman. According to T.S. Kawami (ibid., 73) this relief may depict a member of the Kamnaskired dynasty who retained some power perhaps religious, rather then political, in the Izeh valley.
The acquired frames of all reliefs have been merged in the laboratory of DITAG, with an accuracy of 0.2 mm approximately. Images with photogrammetric digital camera (model Kodak DCS PRO 14m) have also been acquired, that will update the information provided by the laser scanning. These have been elaborated in Turin, in order to obtain digital orthophotos and “Solid Images” of
the scanned surface. Solid Images are digital images where all the pixels contain x, y, z coordinates, providing information in a known reference system so that it is possible to measure angles, distances and areas. Control points on the sculpted surface of the reliefs have been acquired by total station, in order to locate the merged frames in the same reference system. The accuracy of the grid has been verified by triangulation and intersections of the control points.
1c. Elaborated data
The complete 3D digital model of the Hung-e Azhdar sculpted relief and of the natural surface of the boulder is composed by 7.712.000 points, and is rendered by the software SirIO.
The 3D model of the Hung-e Yaralivand rock relief consists of 2.467.745 points, the 3D model of the rock relief of Hung-e Kamalvand consists of 2.378.347 points.
The preliminary elaboration of the data acquired in Hung-e Yaralivand revealed traces of an inscription on the upper part of the sculpted scene, that was no visible by the nude eyes: indeed, this inscription has been deeply eroded and only scanty traces of some letters are detectable. It is an Elymaean inscription in Aramaic language of the south Mesopotamian group very similar to the well known inscription in Hung-e Kamalvand. This inscription has not yet been detected by other previous surveys and is still unpublished. The correct and final reading will be provided afterward by Prof. F. Pennacchietti (University of Turin) and Dr. Marco Moriggi (University of Catania).
2. Topography of the valley of Hung-e Azhdar
A main network of 6 vertices has been fixed by total station (model Leika) following the valley ground: 5 of these vertices have been also acquired by GPS receivers (model Topcon Hiper PRO). Starting from these vertices a further network consisting of 2462 ground control points (GCP) has been fixed by total station on the ground and on the slopes of the valley: these points have been acquired in reflector mode (360° prism) and with reflector lens in order to define elevation by various levelled sections. Vertices and GCP have been acquired in a known reference system.
The relevant map shows that the valley ground is at an elevation of 836-837 m above the sea level (ASL), approximately, and that the investigated area is at an elevation of about 842 m ASL, on the southern slope of the valley (maps 1-3). The area of archaeological interest covers about 4.200 m2 around the sculpted boulder and is located between 3533070-3533130 N and 392610-392690 E m UTM (corresponding approximately to LL: 31°55’43.58’’ N, 49°41’40.96’’ E coordinates).
3. Trial trenches near the boulder of Hung-e Azhdar
3a. Previous situation
The area selected for trial trenches is located at the foot of the mountains surrounding the valley of Hung-e Azhdar, south from the sculpted rock relief depicting the scene of homage or investiture, and extends for about 140 m2. Here the ground slightly slopes towards the centre of the valley and a number of huge boulders, collapsed in antiquity from the mountains’ cliffs, stand over the present surface or are partially wedged in it. This area, denominated Area 1, was partially surveyed during the 1st campaign, revealing clear traces of unauthorized excavations. The first remark has been confirmed by a preliminary reconnaissance during the present campaign: at least 5 irregular holes and 1 trench were still visible on the ground near and far from the boulder, with loose earth heaped in small mounds beside each hole. This situation deeply disturbed the archaeological context.
3b. Trial trenches in Area 1
Three small test-trenches (two of 4 m2 and one of 6 m2) have been opened and proceeding with the excavation two of these trenches have been unified in one trench of about 17 m2. These trenches, denominated HeA 1 001, HeA 1 002 and HeA 1 003, are close to the sculpted boulder: trench HeA 1 001 is about 3,5 m southeast of the boulder, trench HeA 1 002 is at its foot, on its western half, and trench HeA 1 003 were about 5 m south, almost in the centre of Area 1, but have been widened up to 1,5 m from the sculpted surface.
Trench HeA 1 001 is a squared trench of 2x2 m, where the surface seemed untouched in modern times: here excavations started from the surface’s elevation of 842.208 m ASL. The presence of two huge stones hindered the prosecution of the works, while a further stone is of particular interest because it seems to have been placed on purpose, as it covers a layer containing potsherds that continues beyond the excavations’ limits. A gravel layer was reached below the potsherds layers: this covered a layer containing only stones at an elevation of 841.203 m ASL.
Trench HeA 1 002 is a square of 2x2 m as well. Here a modern unauthorized trench
deeply disturbed the archaeological context. In this trench a number of iron arrowheads and a ring with an engraved male head were found, but their pertinence is uncertain because of the modern hole. The same gravel and stones layers of trench HeA 1 001 have been reached at an elevation of 841.258-841.138 m ASL. Trench HeA 1 003 is the largest of Area 1, since it has been widened up to 5x3 m towards trench HeA 1 002 and unified with it, starting from a 1x2 m trench. Surface in this area revealed 4 modern holes that disturbed the underlying context.
For this reason, potsherds were no clearly stratified on the whole area, even if at least 3 main levels have been recognized in proximity of the eastern excavation limit. A number of arrowheads have been found in the northern part of the trench, close to the limits of trench HeA 1 002, together with fragments of handmade terracotta figurines representing horses. In this area, which is the nearest to the sculpted boulder, structures made in undressed stones have been unearthed close to
the surface and also at a deeper level, but, since their remains continued beyond the excavation limits, they have not been completely cleared. Structure SU 11 is the closest to the surface, being at an elevation of 842.178 m ASL, and it consists of quite large stones gathered together in a quadrangular shape. This structure has been partially destroyed by the modern trench cutting the archaeological layers of trench HeA 1 002. SU 11 lies on structure SU 12, which is almost unknown because it is widely hidden below it. Structure SU 13 is the most ancient of them, being partially covered by SU 12. It has a rectangular shape and it is made of undressed stones smaller than those of the upper structures, probably cut for this purpose. Three corners of structure SU 13 have been cleared, showing that it recalls a small platform of 1.3x2.2 m, following the same orientation of the surface of
the boulder and being less than 2 m from it. Potsherds were found in situ between the stones of the structures: they belong to a particular class of organic temper with dark core which indicates incomplete oxidation.
All trenches have been covered.
Hung-e Azhdar, Hung-e Yar alivand, Tang-e Sarvak
(April 10 – May 7, 2010)
The Iranian-Italian Joint Expedition in Khuzistan conducted the 3rd campaign in Hung-e Azhdar, Hung-e Yar alivand, Tang-e Sarvak. Members of the Expedition were Mr. Jafar Mehrkian (ICAR, archaeologist and co-director), Mrs. Yalda Sourani (ICAR, architect), Mr. Mehdi Faragi (ICAR, archaeologist), Mr. Neamatollah Salashoor (archaeologist) and Mr. Loghman Karimi, Ebrahim Ahmedian, for the Iranian side, Mr. Vito Messina (CST-SAAST, archaeologist and co-director), Mr. Paolo Ardissone (DITAG, archaeologist and topographer), and Mrs. Cristina Bonfanti (DITAG, architect), for the Italian side. The Expedition was supported in Izeh by the Ayapir Cultural Heritage CHB.
The aims of the Expedition were:
- excavation at Hung-e Azhdar: during the 2nd campaign, 3 small trenches have been opened in front of the sculpted boulder of Hung-e Azhdar. The excavation revealed archaeological remains in disturbed layers and the presence of superimposed structures made in undressed stones, which have been partially unearthed;
- laser scanning at Hung-e Azhdar: a portion of the Parthian rock relief has been selected to be re-scanned with the purpose of detecting the erosion of the sculpted surface;
- laser scanning at Tang-e Sarvak: laser scanning of the Parthian rock relief of Tang-e Sarvak, known as relief II (or IIA), has been scheduled as practice for the Iranian scholars participating to the training course “Geomatics and Archaeology” held in Turin from January 18th to 29th, 2010.
Operation on the field has been planned in Tehran from April 10th to 14th, 2010, with the full support of the ICAR, and started on April 17th.
1. Excavation at Hung-e Azhdar
1a. Unearthed structures
The topographic surveys carried out in the 1st and 2nd campaigns revealed that a step of about 80 cm separated the small area in front of the Parthian rock relief by the valley: this area was named Area 1, the outer area was named Area 2.
Both Areas 1 and 2 were disturbed by unauthorized trenches opened in modern times (at least 7 in Area 1, several in Area 2), that were already surveyed during the 1st and 2nd campaigns. For this reason, the archaeological context is unclear in many points of the investigated area, even if small parts have been found untouched during excavation.
Excavation in Area 1 exposed about 100 m2 and allowed to brought to light 2 structures in undressed stones, which revealed different phases. The largest structure develops for about 9 m and is oriented East-Westward. The stones were aligned on two parallel rows and formed a front opened to the N, containing a filling of loose earth, stones and rubble (SU 15, SU 16), which creates a sort of terrace in front of the valley. This low terrace risen for about 30 cm from the supposed floor’s level and the stones aligned on its front were both uncut and cut in regular shape, the latter being probably reused on purpose. On this terrace a row of stones was laid to create a sort of step of about 30 cm with the same orientation (SU 14).
This terrace was superimposed on an older structure, probably smaller, that was partially discovered during the 2nd campaign (SU 8). This has the same orientation, is built with smaller stones and was laid on a layer of rubble that revealed no potsherds. Below this layer, there is a thick layer of sediment that contained no potsherds as well and has been perforated in different points up to 1 m in dept (SU 32).
This terrace is aligned with the step separating Area 1 from the rest of the valley (Area 2), which was created placing two big boulders of regular shape (SU 6-HeA 1 001 and SU 18) against the boulders collapsed from the mountain's cliffs and laid on the natural slope of the valley.
At the foot of the sculpted boulder there is a rectangular platform already discovered during the 2nd campaign, which revealed 3 phases (SU 11, 12 and 13). This is also built in undressed stones and is not oriented on the same direction of the terrace, being aligned with the sculpted surface of the boulder. As a vast part of these platforms were cut by a modern unauthorized trench, the upper platforms (SU 11 and 12) were removed in order to clear the most ancient of them and collect stratified pottery: a portion of these structure was indeed untouched.
In Area 1, 2 deep trenches were opened in order to reach the deeper layers: the first trench, is a square measuring 1x1 m, which was opened into the disturbed point of the terrace, the second is a rectangle, measuring about 1,5x2 m, which was opened in the eastern part of Area 1, close to one of the stones creating the step which separates Area 1 from Area 2 (SU 18). Both of these trenches were covered at the end of the excavation.
In front of the platforms (SU 11, 12 and 13) several arrowheads were discovered during the 2nd campaign. During the present campaign further arrowheads were found loose in surface or in the layers close to the surface, while other objects such as small bronze bells and terracotta figurines, broken into fragments, were discovered near the 2nd platform (SU 12).
The tempers of the collected potsherds revealed that a peculiar class of pottery, characterized by a dark core temper, largely prevails on the others.
1b. Proposed restoration
The more recent structure unearthed in Area 1 is preserved for almost all its extension. For this reason both co-directors decided to propose its restoration instead of covering the whole excavated area. It is very clear that the front develops following a straight line, so it is possible to restore it by placing stones of the same size of those in situ and integrating the filling by loose earth in its upper part and by stones or rubble in its lower part. At the same time, the step originating by SU 4 can be integrated by a row of uncut stones in order to recreate the original layout of the structure: in this way, the terrace can be clearly visible to visitors and the archaeological context in front of the Parthian rock relief can be better understood.
2. Laser scanning at Hung-e Azhdar
Laser scanning at Hung-e Azhdar was planned with the purpose of verifying the erosion of the sculpted surface after 2 years from the first acquisition. A single box of about 50x50 cm corresponding to the head of the horse represented in the left half of the scene has been acquired by handy-scan at the same resolution of the former acquisition (2008). This portion of the relief was selected because is particularly exposed to rainwater erosion. The data acquired will be elaborated in the laboratory of DITAG.
3. Laser scanning at Tang-e Sarvak
Laser scanning at Tang-e Sarvak was planned as practice of the training course "Geomatics and Archaeology" held in Turin from January 18th to 29th, 2010. The rock relief selected for acquisition is the so-called relief II (or IIA), representing a scene of investiture. The sculpted surface has been divided into 32 square sectors of about 50x50 cm and acquired by handy-scan at a resolution of 1.17 mm. Both the operations of acquisition and preliminary elaboration of the data were executed by the participants to the course, supervised by specialists of the Polytechnic of Turin. The acquisition lasted 5 days in the period from April 26 to 30, 2010.