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Petra - Blue Chapel & Ridge Church

The Ridge Church The Blue Chapel Ridge Church (left)

Figure 3.54

View of the Ridge Church to the east with the Phase III floors; photo by Neal Bierling, Phoenix Data Systems

Bikai et al (2020)

Restored Blue Chapel (right)

Figure 2.89

View to the southeast; photo by Neil Bierling

Bikai et al (2020)


Introduction
Introduction

The Blue Chapel (aka Building 2 of the Lower Sector) is located partly up the slope of a ridge in Wadi Musa behind the Petra Church (aka the Byzantine Church). The Ridge Church in Sector 1 is located on the top of that slope. ACOR carried out excavations and restoration works there over twelve seasons between 1994 and 2002. Patricia M. Bikai, then assistant director of ACOR, was the overall project director, and Virginia Egan was project assistant director. The North Ridge Project continued under the direction of Megan Perry and S. Thomas Parker, focusing on areas east and north of the churches ( ACOR Jordan website).The Blue Chapel is so-named because of its blue granite columns.

Petra - Introduction Webpage

Maps, Aerial Views, and Plans
Maps, Aerial Views, and Plans

Maps

  • Fig. 2 - Location Map from Jones (2021)

Aerial Views

  • The 3 churches in Google Earth

Site Plans

General Site Plans

Normal Size

  • Fig. 1.1 - Plan of the 3 churches from Bikai et. al. (2020)
  • Fig. 2.1 - Plan of Ridge Church and Blue Chapel from Bikai et. al. (2020)
  • Fig. 3.1 - Wall and feature locus numbers of Ridge Church and Blue Chapel from Bikai et. al. (2020)

Magnified

  • Fig. 1.1 - Plan of the 3 churches from Bikai et. al. (2020)
  • Fig. 2.1 - Plan of Ridge Church and Blue Chapel from Bikai et. al. (2020)
  • Fig. 3.1 - Wall and feature locus numbers of Ridge Church and Blue Chapel from Bikai et. al. (2020)

Phase by phase Site Plans

Normal Size

  • Fig. 3.3 - Plan of Phase I from Bikai et. al. (2020)
  • Fig. 3.28 - Plan of Phase IIA from Bikai et. al. (2020)
  • Fig. 3.30 - Plan of Phase IIB from Bikai et. al. (2020)
  • Fig. 3.48 - Plan of Phase III from Bikai et. al. (2020)
  • Fig. 3.102 - Plan of Phase IV from Bikai et. al. (2020)
  • Fig. 3.121 - Architecture from Phase V Subphase 1 from Bikai et. al. (2020)
  • Fig. 3.123 - Architecture from Phase V Subphase 2 from Bikai et. al. (2020)
  • Fig. 3.137 - Architecture from Phase V Subphase 3 from Bikai et. al. (2020)
  • Fig. 3.147 - Architecture from Phase VI from Bikai et. al. (2020)

Magnified

  • Fig. 3.3 - Plan of Phase I from Bikai et. al. (2020)
  • Fig. 3.28 - Plan of Phase IIA from Bikai et. al. (2020)
  • Fig. 3.30 - Plan of Phase IIB from Bikai et. al. (2020)
  • Fig. 3.48 - Plan of Phase III from Bikai et. al. (2020)
  • Fig. 3.102 - Plan of Phase IV from Bikai et. al. (2020)
  • Fig. 3.121 - Architecture from Phase V Subphase 1 from Bikai et. al. (2020)
  • Fig. 3.123 - Architecture from Phase V Subphase 2 from Bikai et. al. (2020)
  • Fig. 3.137 - Architecture from Phase V Subphase 3 from Bikai et. al. (2020)
  • Fig. 3.147 - Architecture from Phase VI from Bikai et. al. (2020)

Chronology
Phasing

Phase Period Dates Plans Figures/Photos Discussion
I Nabatean 1st century BCE to 1st century CE Fig. 3.3
Discussion

  • Petra's North Ridge contained a segment of the 1st c. B.C. to 1st c. A.D. occupation within the Nabataean capital. The upper sector of the ridge provided virtually unimpeded views of both the city center and the city's back entrance through Wadi Abu `Ullayqa. Because of this strategic importance, the Nabataean military may have utilized the top of the ridge and built a structure at its highest point. - Bikai et al (2020:40)

II Late Roman 1st to mid 4th century CE Fig. 3.28
Fig. 3.30
Discussion

  • First to mid-4th-c. A.D. occupation on Petra's North Ridge remains surprisingly enigmatic. A number of walls post-dating the Phase I architecture and in use during Phase III could have been constructed during this phase. Likewise, as noted earlier, some Phase I walls in area 23 and in areas 1, 3, 4, and 28 may have been constructed during this period. In many cases, establishing a definite date of many post-Phase I and pre-Phase III North Ridge features remains difficult. - Bikai et al (2020:41)

  • This sequence of construction is what was observed in the Petra Church (Fiema et al. 2001: 14). Walls that eventually were incorporated into the church complex were first constructed during this phase. Similar to the North Ridge, almost no artifacts or occupation layers attributed to this phase were identified. Fiema also suggests the scant evidence for Late Roman activities to the clearing and subsequent restoration of the area, presumably instigated by destruction related to the A.D. 363 earthquake (Fiema et al. 2001: 18). - Bikai et al (2020:46)

III Early Byzantine Fig. 3.48
Discussion

  • The Early Byzantine period on the North Ridge saw the conversion of the Nabataean and Late Roman structures at the top of the ridge into the Ridge Church and significant modification to the buildings that would eventually become the Blue Chapel complex (see plan Fig. 3.48). Around the time of the construction of the church, a small installation was constructed in area 34 to the south of the church. 2 - Bikai et al (2020:47)
    Footnotes

    2 Eusebius mentions the founding of churches in Petra in the early 4th c. A.D. (see Schick in Fiema et al. 2001)


  • The Early Byzantine period on the North Ridge heralded the emergence of Christianity as the major imperial religion. In conjunction with this change, the Nabataean buildings at the top of the North Ridge were converted into the Ridge Church complex that included a small building honoring a prominent individual within Petra (figs. 3.100-101). This individual, a member of the military, was commemorated for protecting the city. The information provided by the inscription in the tomb provides a further link between the North Ridge and the military and may suggest that the military constructed the Ridge Church - Bikai et al (2020:57-58)

  • The mid-4th to early 5th-c. construction boom across the western sector of the North Ridge, including the area of the Petra Church, could have been a response to structural damage from the substantive A.D. 363 earthquake. Fiema (Fiema et al. 2001: 18) suggests that the Late Roman complexes in the Petra Church area were robbed of desirable architectural elements and backfilled to prepare the area for new (post-A.D. 363) construction. While no similar evidence for extensive back-filling of Late Roman structures exists on the North Ridge, an architectural disjuncture does appear after the Late Roman phase. Only a few earlier walls are incorporated into Early Byzantine, and eventually, Late Byzantine structures. Presuming the A.D. 363 earthquake caused this shift, architectural modifications on the North Ridge during the Early Byzantine phase likely postdate the mid-4th century - Bikai et al (2020:57-58)

IV Late Byzantine mid 5th - 6th centuries Fig. 3.102
Discussion

  • Expansion of the ecclesiastical buildings on Petra's North Ridge continued during the Late Byzantine period, from the mid-5th-6th centuries (see plan Fig. 3.102). The Ridge Church and the Blue Chapel were renovated during the mid-6th c. with construction of elevated bemas and modification of the apses. The religious visibility of the North Ridge after initial construction of the Ridge Church increased substantially with the construction of the Petra Church lower on the slope in the mid-5th c. (Fiema et al. 2001: 53). The Petra Church construction seems also to correspond with the initial building of the church and chapel at the monastery on Jebel Haroun (Mikkola et al. 2008: 116). The mid-6th c. saw renovation of both of these ecclesiastical structures (Fiema et al. 2001: 77, 80, 91; Mikkola et al. 2008: 133), along with renovation of the Ridge Church and the Blue Chapel - Bikai et al (2020:59)

  • Lower Sector [i.e. Blue Chapel] - Wooden benches were built along the northern, western, and southern perimeter of the chapel. Small rectangular niches for attaching the bench were identified in the walls and floor (figs. 4.44-46, 51); one of the wall niches contained remnants of a peg used to attach the bench to the wall. 14C dating of that piece suggests the bench was constructed between CAL A.D. 530 and 640 [95.4% (2σ) calibrated age ranges, relative area under distribution 0.978 (Stuiver and Reimer 1993)]. Another sample of charcoal from locus 1148, probably from the burning of church furnishings by later occupants (figs. 3.134-35), dates to CAL A.D. 527-651 [95.4% (2σ) calibrated age ranges, relative area under distribution 0.801 (Stuiver and Reimer 1993)], approximately the same date range as the bench peg recovered from within the Blue Chapel. The nature of the architectural renovations of the Blue Chapel point to a mid-6th-c. date for these modifications. - Bikai et al (2020:63)

  • The Late Byzantine period saw a peak in ecclesiastical activity on the North Ridge, and perhaps Petra as a whole. In the early part of this phase, the Blue Chapel building 2 was converted into a triapsidal structure, which included construction of an elevated bema, an elaborate ambo, a thronos, a rectangular synthronon, and wooden benches along the aisles. 14C analysis of remnants of the bench installation and of the architectural features of the church imply this conversion occurred in the mid-6th c. A.D. This is concurrent with renovations of the two other ecclesiastical structures on the North Ridge: the Ridge Church and the Petra Church. The Ridge Church now contained floor and wall mosaics, an elevated bema, and marble furnishings. - Bikai et al (2020:64)

V-1 Early Islamic
Subphase 1
6th - 8th centuries CE Fig. 3.121
Discussion

  • The Early Islamic period on the North Ridge is categorized by occupation of the former ecclesiastical structures by 6th—8th-c. residents of Petra, ending with extensive earthquake destruction in the 8th c. A.D. - Bikai et al (2020:64)

  • At some point in the 7th c. A.D., the Ridge Church and Blue Chapel complex on the North Ridge were abandoned, as was the Petra Church (see plan Fig. 3.121). In most cases, a thin, ca. 10-30 cm layer of sand built up within the buildings' rooms, although some areas saw what appears to be almost immediate occupation by the remaining residents of Petra.

    Upper Sector [Ridge Church]

    The Ridge Church and surrounding area on top of the ridge were left abandoned during this period. Sandy soil layer locus 607 built up within the plaza in front of the Ridge Church and sandy deposits loci 900 and 901 filled in the water channel (locus 902) cut into the plaza. Compact silt and clay also covered the stairs leading up to the Ridge Church plaza (loci 930, 931, and 1223).

    Lower Sector [Blue Chapel]

    Building 1

    Building 1 saw a short period of abandonment in many sectors, resulting in the deposition of sandy soil layers locus 967 in area 14, and the lower levels of locus 1245 in area 15, locus 1236 in area 16, and locus 1244 in area 18. These semi-compact deposits contained few artifacts. Areas 11 and 17, however, contained evidence for domestic occupation directly upon the floor level (see fig. 3.39). These layers contain 6th—8th-c. A.D. storage jars and other vessels and cooking debris. Therefore these rooms either may have seen the earliest inhabitation of this period in the complex, or Subphase 2 residents cleared the floor of Subphase 1 deposits before occupying these areas.

    Building 2

    The rooms within building 2 displayed little activity during this subphase of the Early Islamic period besides accumulation of raw materials such as marble.

    ... Several explanations can be proposed for the abandonment of these structures; these will be discussed in Chapter 9. The date of the abandonment, however, remains speculative. Ceramic lamps from these strata date no later than the 1st-3rd centuries A.D. (Barrett 2008) and clearly are secondary deposits. Perhaps destruction of the Petra Church by fire in the late 6th c. made the Blue Chapel complex unnecessary. Local officials did not attempt to rebuild the Petra Church (Fiema et al. 2001: 94), which may indicate a decrease in Petra's population due to the dwindling economic base and the gradual collapse of the infrastructure, particularly the water system. Before the Blue Chapel complex was abandoned, the structure was cleared of portable artifacts except for some glass objects left in area 20. This period of abandonment could have lasted at most 100 years before the post-Byzantine period residents of Petra began to occupy the structures, as described below [Early Islamic Subphase 2].
    - Bikai et al (2020:64-65)

V-2 Early Islamic
Subphase 2
6th - 8th centuries CE Fig. 3.123 Fig. 3.134
Fig. 3.135
Fig. 3.136
Fig. 3.122
Discussion

  • The Early Islamic period on the North Ridge is categorized by occupation of the former ecclesiastical structures by 6th—8th-c. residents of Petra, ending with extensive earthquake destruction in the 8th c. A.D. - Bikai et al (2020:64)

  • Subphase 2 - After a short period of abandonment of the North Ridge during Early Islamic Subphase 1, many Petra residents made use of the empty structures for domestic and other activities (see plan in Fig. 3.123). The post-Byzantine occupants of the North Ridge left behind thick layers of occupational debris and concentrations of burnt soil, likely from cooking fires, within the structures. Additionally, they explored the hillside for tombs to loot, even pulling up the floor slabs within the Byzantine-period structures in their search. Tombs opened by this population soon filled with occupational debris and architectural fragments from the nearby structures. - Bikai et al (2020:66)

  • Lower Sector - Building 2 - Ashy Deposits beneath fallen columns

    The Blue Chapel also contained much evidence of human domestic activity, such as burning and ash from small cooking fires, animal bones, and storage and cooking vessels (Fig. 3.134). ... The large amount of cooking occurring in this room suggests the roof had partially collapsed, providing some ventilation. Loci 1064, 1065, 1091, and upper levels of 1055 and lower levels of 1050 in the central aisle, loci 1089, 1091, and 1148 in the southern aisle, loci 1091 and 1178 in the northern aisle, the upper levels of loci 1094 and 1183 in the bema area, and upper levels of locus 1172 under column drums that fell during Early Islamic Phase 3 all contained a large amount of occupational debris (Fig. 3.135 and 3.136 - see also Fig. 3.122).

    ... Occupation of at least part of the Blue Chapel complex likely ceased due to earthquake-related structural instability and collapse in the mid-8th century. A date provided by 14C analysis of an animal bone recovered from immediately underneath a fallen column (drum no. 2; Fig. 3.136) in the Blue Chapel indicates that the animal died between A.D. 658 and 782 CAL [95.4% (2σ) calibrated age ranges, relative area under distribution 0.942 (Stuiver and Reimer 1993)]. The column presumably fell shortly after this animal's death and consumption by the buildings' occupants. Two earthquakes during this period affected the Petra region, according to earthquake chronologies constructed by Russell (1985) and Guidoboni (1994): the A.D. 672 earthquake that impacted Gaza, Ashkelon, and Ramle along the Mediterranean coast [JW: a dubious event1], and the massive A.D. 748/9 seismic event(s) that affected northeastern Egypt through northern Mesopotamia. Evidence from the Blue Chapel suggests that the A.D. 748/9 earthquake, which strongly affected Petra, likely was responsible for initial collapse of the columns.
    - Bikai et al (2020:68-70)
    Footnotes

    1 Russell (1985) characterizes this earthquake report as follows:

    According to Amiran (1950-51: 226) [JW: an error-prone catalog], an earthquake in 672 damaged Gaza, Ashqelon, and Ramle. This is the same description given by Robinson for this event (1865: 325-26). Both scholars referred to volume 16 of Karl Ritter's Erdkunde (1852) for documentary support. But Ritter did not explicitly note ancient documentation for this event (1852: 64, 70), and none has yet been located. Since there is sufficient reason to doubt that a localized earthquake would have occurred in the vicinity of the Ramle/Lydda or Balah/Gaza epicenters at this time, the future use of this date will have to be supported by explicit reference to the ancient text or texts that, presumably, document this event. There is currently insufficient evidence to adequately evaluate its occurrence.
    Guidoboni et al (1994) do not list an earthquake in 672 CE and an article by Guidoboni (1994) is not listed in the reference section of Guidoboni et al (1994) or Guidoboni and Comastri (2005). There is no 672 CE earthquake in the catalog of Ambraseys (2009) as well.

V-3 Early Islamic
Subphase 3
6th - 8th centuries CE [JW: and maybe later] Fig. 3.137 Fig. 3.139
Fig. 3.138
Fig. 3.141
Fig.3.142
Fig. 3.143a
Fig. 3.143b
Fig. 3.144a
Fig. 3.144b
Fig. 3.145
Fig. 3.146
Discussion

  • The Early Islamic period on the North Ridge is categorized by occupation of the former ecclesiastical structures by 6th—8th-c. residents of Petra, ending with extensive earthquake destruction in the 8th c. A.D. - Bikai et al (2020:64)

  • SUBPHASE 3

    From the 8th c. A.D. on, the abandoned structures suffered extensive damage from repeated earthquakes
    (see plan Fig. 3.137). The North Ridge appears to have experienced some human activity, but this presence is difficult to date.

    UPPER SECTOR

    Unfortunately, extensive shifting of debris to clear the plateaus for agriculture during the Late Islamic/Modem phase inhibits understanding the sequence of building deterioration on the North Ridge. As a result, almost no evidence of this subphase exists at the top of the North Ridge, except for a small area of compact sand and building debris in area 33 (loci 904, 925, and 1205) and in areas 6 and 7 (locus 1221). Some of the debris that collected in the Ridge Church courtyard (area 3) attributed to Phase VI might date to this phase as well (e.g., loci 201, 207, 209, 307=418).

    LOWER SECTOR

    Building 1

    Some evidence of this subphase exists within in the area of building 1 despite Phase VI preparation of this plateau for agriculture. Locus 1108 from area 11, loci 969, 1004, 1009, and 1010 from area 14, loci 1016, 1113, 1118, and the upper levels of 1245 in area 15, loci 1231 and 1233 in area 16, loci 1034, 1036, 1043, 1044, and 1118 in area 17, and loci 1016, 1017, 1018, 1024, 1025, 1242, and 1243 from area 18 all contained tumble from post-earthquake building collapse (Fig. 3.139). In addition, soil layers loci 961 and 962 built up above the "street" area north of building 1's wall 909 (Fig. 3.138).

    Building 2

    Building 2 contains the most evidence for Early Islamic Sub-phase 3 building collapse on the North Ridge. Thick (1-1.5 m) layers of building tumble were discovered in the stairway in area 19 (loci 1052, 1057, 1071, and the upper levels of 1114, and 1115); the entry hall in area 24 (loci 1109 and the upper levels of 1130; fig. 3.140); area 20 (loci 973, 1027, and 1177); the atrium (area 23, the lower level of loci 1037 and 1125 and loci 1039, 1041, 1140, 1145, and 1165 in the southern half of the room, the middle levels of locus 1132 and loci 1173, 1176, 1189, 1190, 1201, 1207, 1220, 1225, and 1228 in the northern half of the room); and the Blue Chapel (area 25, the upper levels of loci 1048, 1050, and 1087 and loci 1062, 1063, and 1088 in the central aisle, the upper levels of locus 1087 and loci 1088, 1103, and 1153 in the northern aisle, loci 1087, 1088, and 1147 in the southern aisle, and locus 1088 in the bema). Many architectural features appeared to have fallen in one destructive episode, such as the cornice along the western and northern walls of the entry hall, as well as the vault of the area (Figs. 3.141 and 3.142), and the columns in the Blue Chapel (Figs. 3.143, 3.144, 3.145, and 3.146). Additionally, clear evidence for collapse of the second story was discovered within area 20. A number of floor slabs probably from the upper floor were noted ca. 0.50 m from the room's floor level in loci 973, 1177, and the upper levels of 1030.

    SUMMARY

    At some point after the North Ridge structures were abandoned during the late 6th or early 7th c., they began to be used for domestic activities. Occupants selected these areas for cooking and food preparation, leaving behind numerous broken 6th-8th-c. water storage jars and other ceramic vessels, animal bones, and burnt debris. Residents slightly modified the structures for their new purpose, including constructing a kitchen area in the Ridge Church complex and blocking off rooms in building 1 of the Blue Chapel complex. The Blue Chapel complex residents found little in the way of built-in furnishings in the abandoned structure and did not construct anything other than the walls mentioned above, unlike in the Petra Church (Fiema et al. 2001: 95). These individuals also discovered that many of the 1st c. A.D. tombs underlying the structures contained a wealth of raw materials, and Tomb 2, directly to the south of the Ridge Church, was opened and rifled during this period.
    - Bikai et al (2020:70-71)

VI Late Islamic to Modern post 8th century CE Fig. 3.147
Discussion

  • Post-8th-c. human activity on the North Ridge is rather ephemeral and not easily datable. There is nothing indicating a permanent population until the modern era. The evidence for post-8th-c. occupation consists mainly of agricultural terracing and possibly the construction of retaining walls within the Blue Chapel complex and Petra Church (see plan in Fig. 3.147). A small series of terraces also was constructed within areas 6, 7, 8, and 9 above the Nabataean and Byzantine staircase. Additionally, building rubble was cleared from an area demarcated by the still-standing columns within the central portion of the Atrium in building 2, possibly for agricultural purposes. These activities culminated with clearing of the North Ridge and the area of building 1 for placement of Bedouin tents and agricultural fields and the construction of terraces in the modern era. - Bikai et al (2020:73)


  • SUMMARY

    The Blue Chapel and Ridge Church were not likely reoccupied extensively following the repeated rounds of earthquake-related collapse. Evidence for human activity on the North Ridge from this phase includes agricultural terracing and the construction of walls within area 23.

    Establishing the date when these activities occurred, however, remains difficult. Few diagnostic ceramics have been recovered from these strata, and extensive clearing of the area during the past 200 years has obliterated the stratigraphic integrity of many areas. Apparently, occupants of the North Ridge either lived elsewhere or led a primarily nomadic lifestyle, as little evidence for domestic occupation was recovered, with the exception of ashy debris in areas 7, 9, and 33. Extensive occupation of the North Ridge presumably resumed in the 19th c. with the construction of small windbreaks and agricultural terraces, in addition to extensive clearing of plateaus created by the ancient structures for Bedouin tents or agricultural plots.
    - Bikai et al (2020:73)

Phase III - no evidence for 363 CE earthquake

Bikai et al (2020:41) surmise that cleaning and restoration after the 363 CE earthquake may have removed evidence of one of the 363 CE Cyril Quakes.

Phase V-1 Earthquake ? - Late 6th century CE

Jones (2021:Table 1) notes that early 7th century Phase V-1 abandonment reported by Perry in Bikai et al (2020:58,64) could have been caused by a late 6th century earthquake.

Phase V-3 CE earthquake - mid 8th century CE

Maps, Plans, and Figures

Maps, Plans, and Figures

  • Fig. 3.1 - Wall and feature locus numbers of Ridge Church and Blue Chapel from Bikai et. al. (2020)
  • Fig. 3.123 - Architecture from Phase V; Subphase 2 from Bikai et. al. (2020)
  • Fig. 3.137 - Architecture from Phase V; Subphase 3 from Bikai et. al. (2020)
  • Fig. 3.136 - Fallen column underneath which an animal bone provided a 14C date - from Bikai et. al. (2020)
  • Fig. 3.140 - Rock tumble from Bikai et. al. (2020)
  • Fig. 3.141 - Earthquake collapse of cornice and vault stones from Bikai et. al. (2020)
  • Fig. 3.142 - Vault stones re-used as building elements from Bikai et. al. (2020)
  • Fig. 3.143a - Fallen Columns from Bikai et. al. (2020)
  • Fig. 3.143b - Fallen Columns from Bikai et. al. (2020)
  • Fig. 3.144a - Punctured Floor from Bikai et. al. (2020)
  • Fig. 3.144b - Punctured Floor from Bikai et. al. (2020)
  • Fig. 3.145 - Percussion fractures on a column drum from Bikai et. al. (2020)
  • Fig. 3.146 - Chipped column base from Bikai et. al. (2020)

Discussion

Archaeoseismic evidence comes from Lower Sector Building 2 in the Blue Chapel. Perry in Bikai et al (2020:69-70) reports the following:
Occupation of at least part of the Blue Chapel complex likely ceased due to earthquake-related structural instability and collapse in the mid-8th century. A date provided by 14C analysis of an animal bone recovered from immediately underneath a fallen column (drum no. 2; fig. 3.136) in the Blue Chapel indicates that the animal died between A.D. 658 and 782 CAL [95.4% (2σ) calibrated age ranges, relative area under distribution 0.942 (Stuiver and Reimer 1993)]. The column presumably fell shortly after this animal's death and consumption by the buildings' occupants. Two earthquakes during this period affected the Petra region, according to earthquake chronologies constructed by Russell (1985) and Guidoboni (1994): the A.D. 672 earthquake that impacted Gaza, Ashkelon, and Ramle along the Mediterranean coast [JW: a dubious event1], and the massive A.D. 748/9 seismic event(s) that affected northeastern Egypt through northern Mesopotamia. Evidence from the Blue Chapel suggests that the A.D. 748/9 earthquake, which strongly affected Petra, likely was responsible for initial collapse of the columns.
Footnotes

1 Russell (1985) characterizes this earthquake report as follows:

According to Amiran (1950-51: 226) [JW: an error-prone catalog], an earthquake in 672 damaged Gaza, Ashqelon, and Ramle. This is the same description given by Robinson for this event (1865: 325-26). Both scholars referred to volume 16 of Karl Ritter's Erdkunde (1852) for documentary support. But Ritter did not explicitly note ancient documentation for this event (1852: 64, 70), and none has yet been located. Since there is sufficient reason to doubt that a localized earthquake would have occurred in the vicinity of the Ramle/Lydda or Balah/Gaza epicenters at this time, the future use of this date will have to be supported by explicit reference to the ancient text or texts that, presumably, document this event. There is currently insufficient evidence to adequately evaluate its occurrence.
Guidoboni et al (1994) do not list an earthquake in 672 CE and an article by Guidoboni (1994) is not listed in the reference section of Guidoboni et al (1994) or Guidoboni and Comastri (2005). There is no 672 CE earthquake in the catalog of Ambraseys (2009) as well.

Perry in Bikai et al (2020:470) noted the following:
Occupation within the Ridge Church and the Blue Chapel complex halted during the 8th c.: in the Blue Chapel complex, this occurred concurrent with or immediately before significant collapse of part of these structures. The pattern of collapse, particularly evidence for the dramatic tumble of the columns in the Blue Chapel, would point to a seismic event as the cause (figs. 3.140-46; 9.9). Ceramic evidence and a 14C date of carbonized animal bone found directly under one of the columns (fig. 3.136) implicates the sizeable earthquake of A.D. 748/749 that has been documented extensively in the region. The Petra Church suffered a similar fate, marked by collapsed stone in the interior of the basilica, the atrium, and surrounding rooms from a half a meter to three meters deep on top of occupational debris (Fiema 2001: 105), which Fiema (2001: 115-18) attributes to an A.D. 672 seismic event [JW: Dubious event - see footnote above]. This was followed by further collapse in the church and in the baptistery from the A.D. 748/749 earthquake. The Jabal Haroun church and chapel experienced significant destruction also attributed to a mid- to late-7th c. earthquake (Mikkola et al. 2008: 136). These structures were rebuilt, only to be damaged again in the 748/749 earthquake (Mikkola et al. 2008: 148), after which only the chapel was used for ecclesiastical purposes (Mikkola et al. 2008: 157). No evidence for an earlier phase of destruction dating to the late 7th c. was discovered in the Blue Chapel complex. However, continuous seismic events after the 8th c. caused additional damage to the abandoned, collapsed Blue Chapel complex structures. This damage included the collapse of a cornice along the western and northern walls of the Blue Chapel entry hall and the collapse of part of the upper story (see figs. 3.141-42).
Perry in Bikai et al (2020:70-71) identified archaeoseismic evidence from "one apparent destructive earthquake" in Phase V subphase 3 deposits in Building 2 of the Lower Sector (i.e. the Blue Chapel). This "one apparent destructive earthquake" appears to be a mid 8th century CE earthquake.
Building 2 contains the most evidence for Early Islamic Sub-phase 3 building collapse on the North Ridge. Thick (1-1.5 m) layers of building tumble were discovered in
  • the stairway in area 19 (loci 1052, 1057, 1071, and the upper levels of 1114, and 1115)
  • the entry hall in area 24 (loci 1109 and the upper levels of 1130; fig. 3.140)
  • area 20 (loci 973, 1027, and 1177)
  • the atrium (area 23, the lower level of loci 1037 and 1125 and loci 1039, 1041, 1140, 1145, and 1165 in the southern half of the room, the middle levels of locus 1132 and loci 1173, 1176, 1189, 1190, 1201, 1207, 1220, 1225, and 1228 in the northern half of the room)
  • the Blue Chapel (area 25, the upper levels of loci 1048, 1050, and 1087 and loci 1062, 1063, and 1088 in the central aisle, the upper levels of locus 1087 and loci 1088, 1103, and 1153 in the northern aisle, loci 1087, 1088, and 1147 in the southern aisle, and locus 1088 in the bema)
Many architectural features appeared to have fallen in one destructive episode, such as
  • the cornice along the western and northern walls of the entry hall, as well as the vault of the area (figs. 3.141 and 3.142)
  • the columns in the Blue Chapel (figs. 3.143 a&b, 3.144 a&b, 3.145 and 3.146)
Additionally, clear evidence for collapse of the second story was discovered within area 20. A number of floor slabs probably from the upper floor were noted ca. 0.50 m from the room's floor level in loci 973, 1177, and the upper levels of 1030.

Phase VI earthquakes - after mid 8th century CE

Maps, Plans, Sections, and Figures

Maps, Plans, Sections, and Figures

  • Fig. 3.1 - Wall and feature locus numbers of Ridge Church and Blue Chapel from Bikai et. al. (2020)
  • Fig. 3.137 - Architecture from Phase V; Subphase 3 from Bikai et. al. (2020)
  • Fig. 3.139 - Section showing earthquake debris in area 18 from Bikai et. al. (2020)

Discussion

Perry in Bikai et al (2020:70) noted that from the 8th c. A.D. on, the abandoned structures suffered extensive damage from repeated earthquakes. Perry in Bikai et al (2020:70) also noted that locis from areas 11, 14, 15, 17, and 18 in Building 1 of the Lower Sector all contained tumble from post-earthquake building collapse (fig. 3.139).

Seismic Effects
Phase V-1 Earthquake ? - Late 6th century CE

Effect Location Image(s) Description(s)
Collapse and Debris Blue Chapel
Building 2
Area 25
Probes 5&7


Fig. 3.122
Discussion

  • PHASE V. EARLY ISLAMIC

    SUBPHASE 1

    LOWER SECTOR

    Building 2 (Blue Chapel)

    The rooms within building 2 displayed little activity during this subphase of the Early Islamic period besides accumulation of raw materials such as marble. Sandy soil layers loci 1066, 1067, 1068, and 1076 built up within the stairway in area 19, locus 1134 within the entry hall, the lower portions of loci 1191, 1045 and 1165 within the atrium, and the lower portions of loci 1030 and 1180 within area 20. Decorative elements, likely from the chapel, were found in these layers, such as a polycandelon fragment in the entry hall (NPR catalogue no. 142), and a complete glass lamp (NPR catalogue no. 146) and a small iron cross (NPR catalogue no. 147) in area 20. Loose sand (locus 1171) also clogged the drain under the atrium (locus 1185), and silt (locus 1182) filled the drainage channel (locus 1184) leading south from the atrium. In addition, sandy subsoil covered the aisles, bema, and apses of the Blue Chapel (loci 1055, 1069, 1070, 1074 and 1099.03 within the central aisle, locus 1090 within the southern aisle, loci 1099.14 and 1179, within the northern aisle, locus 1164 in the southern apse area, locus 1094 above the elevated bema, and loci 1087, 1099.02, 1183, and the lower portion of locus 1172 in scattered areas of the chapel; see fig. 3.122). Finally, sand was deposited to the south of the Blue Chapel in area 21 (locus 1248). The abandonment layers from the Blue Chapel and area 20 contained quantities of broken glass from the chandelier pieces and other glass vessels being stored in this room. It probably was during this period that some individuals ransacked the Blue Chapel, for many pulpit and chancel screen fragments were discovered in these strata.

    Several explanations can be proposed for the abandonment of these structures; these will be discussed in Chapter 9. The date of the abandonment, however, remains speculative. Ceramic lamps from these strata date no later than the 1st-3rd centuries A.D. (Barrett 2008) and clearly are secondary deposits. Perhaps destruction of the Petra Church by fire in the late 6th c. made the Blue Chapel complex unnecessary. Local officials did not attempt to rebuild the Petra Church (Fiema et al. 2001: 94), which may indicate a decrease in Petra's population due to the dwindling economic base and the gradual collapse of the infrastructure, particularly the water system. Before the Blue Chapel complex was abandoned, the structure was cleared of portable artifacts except for some glass objects left in area 20. This period of abandonment could have lasted at most 100 years before the post-Byzantine period residents of Petra began to occupy the structures, as described below.
    - Perry in Bikai et al (2020:64)

  • POST BYZANTINE PETRA

    The ecclesiastical presence at Petra did not last beyond the late 6th c. or early 7th c. A.D., although the monastic complex on Jabal Haroun continued to have a sacred function into the late 8th to early 9th century (Mikkola et al. 2008: 159). Only a couple of decades after the first series of renovations in the Petra Church, another set of decorative changes was being installed in the late 6th century. Unfortunately, a fire destroyed the structure (and resulted in the carbonization of the Petra papyrus archive stored in a room adjacent to the sanctuary), and the church was never rebuilt (Fiema 2001: 94). In the next few years, the Ridge Church and the Blue Chapel complex also were cleared of most liturgical and other material objects and left abandoned. This period of inactivity is marked by a thin layer of sterile windblown sand that covered many of the floors in these structures. The reason for the abandonment of these two other ecclesiastical structures may be linked to the destruction of the Petra Church, which provided the impetus to shut down formal ecclesiastical presence in Petra. In addition, evidence from the church and chapel on Jabal Haroun show a period of significant destruction and fire, which is attributed to earthquakes ca. 551 and 559 (Mikkola et al. 2008: 119). Could this tremor have destabilized the other ecclesiastical structures within Petra in the mid-6th c., resulting in their abandonment? This would provide even less reason for recovery of the Petra Church after its fire. Unlike the churches within Petra, the complex on Jabal Haroun, important due to its association with Aaron/Haroun, was rebuilt (Mikkola et al. 2008: 119).

    The Ridge Church and Blue Chapel complex remained largely intact after their abandonment and provided shelter for domestic activities beginning in the late 6th to early 7th centuries. Some structures were modified for this purpose, such as the construction of the kitchen installation in the Ridge Church plaza (area 26) and a small table and bench installation in area 28 near the Ridge Church. Similar modifications were made to the Petra Church during the same period (Fiema 2001: 95, 98) and in the main church on Jabal Haroun after it went out of ecclesiastical use in the mid-8th century (Mikkola et al. 2008: 149-50).
    - Perry in Bikai et al (2020:468-469)

Phase V-3 CE earthquake - mid 8th century CE

  • Archaeoseismic evidence all comes from the Blue Chapel (Lower Sector Building 2)
Effect Location Image(s) Description(s)
Fallen Column Area 25

a fallen column (drum no. 2)
Fallen Columns Area 25

View to the West
View to the East
Orientation and identification of Fallen Columns Area 25

Drawing shows orientation of Fallen Columns in the Blue Chapel as well as their numerical identification (1-11)
Percussion Fractures on Column Drum Area 25

Drum 2 with percussion fractures around its edge, caused by the column drums rocking during an earthquake - Bikai et al (2020)
Fractured Column Drum Area 25

Column drum 9 and the northwest base
Damage to the Bema Floor Area 25

View to the East
View to the South
thought to be caused by fall of column drum 3
Rock Tumble Area 24

includes fallen door lintel
Collapse of cornice and vault stones with courses preserved Area 24

along the western and northern walls of the entry hall
Re-used Building elements Area 24

along the western and northern walls of the entry hall. Bikai et al (2020) suggested that these re-used building elements were taken from the collapse of the vault.
Second Storey Collapse Area 20

clear evidence for collapse of the second story was discovered within area 20. A number of floor slabs probably from the upper floor were noted ca. 0.50 m from the room's floor level in loci 973, 1177, and the upper levels of 1030. - Perry in Bikai et al (2020:70)
Thick (1-1.5 m) layers of building tumble Stairway in Area 19

loci 1052, 1057, 1071, and the upper levels of 1114, and 1115
Thick (1-1.5 m) layers of building tumble entry hall in area 24

loci 1109 and the upper levels of 1130
Thick (1-1.5 m) layers of building tumble Area 20

loci 973, 1027, and 1177
Thick (1-1.5 m) layers of building tumble Area 23
the atrium

lower level of loci 1037 and 1125 and loci 1039, 1041, 1140, 1145, and 1165 in the southern half of the room, the middle levels of locus 1132 and loci 1173, 1176, 1189, 1190, 1201, 1207, 1220, 1225, and 1228 in the northern half of the room
Thick (1-1.5 m) layers of building tumble Area 25

upper levels of loci 1048, 1050, and 1087 and loci 1062, 1063, and 1088 in the central aisle, the upper levels of locus 1087 and loci 1088, 1103, and 1153 in the northern aisle, loci 1087, 1088, and 1147 in the southern aisle, and locus 1088 in the bema

Phase VI earthquakes - after mid 8th century CE

Effect Location Image(s) Description(s)
Earthquake debris Blue Chapel
Building 1
Areas 11, 14, 15, 17, and 18

  • locis from areas 11, 14, 15, 17, and 18 in Building 1 of the Lower Sector all contained tumble from post-earthquake building collapse. - Perry in Bikai et al (2020:70)

Deformation Maps
Phase V-3 CE earthquake - mid 8th century CE

Deformation Map

modified by JW from Fig. 3.137 (Phase V-3 plan) of Bikai et al (2020)

Intensity Estimates
Phase V-1 Earthquake ? - Late 6th century CE

Effect Location Image(s) Description(s) Intensity
Collapse and Debris Blue Chapel
Building 2
Area 25
Probes 5&7


Fig. 3.122
Discussion

  • PHASE V. EARLY ISLAMIC

    SUBPHASE 1

    LOWER SECTOR

    Building 2 (Blue Chapel)

    The rooms within building 2 displayed little activity during this subphase of the Early Islamic period besides accumulation of raw materials such as marble. Sandy soil layers loci 1066, 1067, 1068, and 1076 built up within the stairway in area 19, locus 1134 within the entry hall, the lower portions of loci 1191, 1045 and 1165 within the atrium, and the lower portions of loci 1030 and 1180 within area 20. Decorative elements, likely from the chapel, were found in these layers, such as a polycandelon fragment in the entry hall (NPR catalogue no. 142), and a complete glass lamp (NPR catalogue no. 146) and a small iron cross (NPR catalogue no. 147) in area 20. Loose sand (locus 1171) also clogged the drain under the atrium (locus 1185), and silt (locus 1182) filled the drainage channel (locus 1184) leading south from the atrium. In addition, sandy subsoil covered the aisles, bema, and apses of the Blue Chapel (loci 1055, 1069, 1070, 1074 and 1099.03 within the central aisle, locus 1090 within the southern aisle, loci 1099.14 and 1179, within the northern aisle, locus 1164 in the southern apse area, locus 1094 above the elevated bema, and loci 1087, 1099.02, 1183, and the lower portion of locus 1172 in scattered areas of the chapel; see fig. 3.122). Finally, sand was deposited to the south of the Blue Chapel in area 21 (locus 1248). The abandonment layers from the Blue Chapel and area 20 contained quantities of broken glass from the chandelier pieces and other glass vessels being stored in this room. It probably was during this period that some individuals ransacked the Blue Chapel, for many pulpit and chancel screen fragments were discovered in these strata.

    Several explanations can be proposed for the abandonment of these structures; these will be discussed in Chapter 9. The date of the abandonment, however, remains speculative. Ceramic lamps from these strata date no later than the 1st-3rd centuries A.D. (Barrett 2008) and clearly are secondary deposits. Perhaps destruction of the Petra Church by fire in the late 6th c. made the Blue Chapel complex unnecessary. Local officials did not attempt to rebuild the Petra Church (Fiema et al. 2001: 94), which may indicate a decrease in Petra's population due to the dwindling economic base and the gradual collapse of the infrastructure, particularly the water system. Before the Blue Chapel complex was abandoned, the structure was cleared of portable artifacts except for some glass objects left in area 20. This period of abandonment could have lasted at most 100 years before the post-Byzantine period residents of Petra began to occupy the structures, as described below.
    - Perry in Bikai et al (2020:64)

  • POST BYZANTINE PETRA

    The ecclesiastical presence at Petra did not last beyond the late 6th c. or early 7th c. A.D., although the monastic complex on Jabal Haroun continued to have a sacred function into the late 8th to early 9th century (Mikkola et al. 2008: 159). Only a couple of decades after the first series of renovations in the Petra Church, another set of decorative changes was being installed in the late 6th century. Unfortunately, a fire destroyed the structure (and resulted in the carbonization of the Petra papyrus archive stored in a room adjacent to the sanctuary), and the church was never rebuilt (Fiema 2001: 94). In the next few years, the Ridge Church and the Blue Chapel complex also were cleared of most liturgical and other material objects and left abandoned. This period of inactivity is marked by a thin layer of sterile windblown sand that covered many of the floors in these structures. The reason for the abandonment of these two other ecclesiastical structures may be linked to the destruction of the Petra Church, which provided the impetus to shut down formal ecclesiastical presence in Petra. In addition, evidence from the church and chapel on Jabal Haroun show a period of significant destruction and fire, which is attributed to earthquakes ca. 551 and 559 (Mikkola et al. 2008: 119). Could this tremor have destabilized the other ecclesiastical structures within Petra in the mid-6th c., resulting in their abandonment? This would provide even less reason for recovery of the Petra Church after its fire. Unlike the churches within Petra, the complex on Jabal Haroun, important due to its association with Aaron/Haroun, was rebuilt (Mikkola et al. 2008: 119).

    The Ridge Church and Blue Chapel complex remained largely intact after their abandonment and provided shelter for domestic activities beginning in the late 6th to early 7th centuries. Some structures were modified for this purpose, such as the construction of the kitchen installation in the Ridge Church plaza (area 26) and a small table and bench installation in area 28 near the Ridge Church. Similar modifications were made to the Petra Church during the same period (Fiema 2001: 95, 98) and in the main church on Jabal Haroun after it went out of ecclesiastical use in the mid-8th century (Mikkola et al. 2008: 149-50).
    - Perry in Bikai et al (2020:468-469)

VIII +
The archeoseismic evidence requires a minimum Intensity of VIII (8) when using the Earthquake Archeological Effects chart of Rodríguez-Pascua et al (2013: 221-224).

Phase V-3 CE earthquake - mid 8th century CE

Effect Location Description Intensity
Fallen Columns Blue Chapel
Area 25

  • fallen column (drum no. 2; fig. 3.136 ) View to West View to East
  • Orientation and identification of Fallen Columns -
  • Percussion Fractures on Column Drum -
  • Fractured Column drum 9 and the northwest base -
  • Damage to Bema floor from collapsed columns - View to East - View to south -
VI +
Collapsed Vault Blue Chapel
Area 24

  • Collapse of cornice and vault stones -
  • Collapsed Vault Stones -
VIII +
Collapsed Walls Blue Chapel
Area 20

  • clear evidence for collapse of the second story was discovered within area 20. A number of floor slabs probably from the upper floor were noted ca. 0.50 m from the room's floor level in loci 973, 1177, and the upper levels of 1030. - Perry in Bikai et al (2020:70)
VIII +
The archeoseismic evidence requires a minimum Intensity of VIII (8) when using the Earthquake Archeological Effects chart of Rodríguez-Pascua et al (2013: 221-224).

Notes and Further Reading
References
Wikipedia page for Ridge Church