Josie Newbold and Dr. Cynthia Finlayson, Department of Anthropology
Petra, Jordan is famous for being the city carved out of red sandstone cliffs. The builders of Petra were the Nabataeans, a people believed to be nomadic at one point in time, who settled in a desert and created a vast empire. They were renowned for their canals and water control systems. However, this city fell into ruins and was abandoned sometime after in earthquake in 749 AD. As part of the project that I am working on, I travelled to Petra, Jordan along with a team of archaeologists and several geology professors in order to study a seep of water emerging from the Ad-Deir monument in an attempt to try and determine the origin of the water. While in Petra, I also analyzed the pattern of fractures and faulting that occurred due to the Dead Sea rifting.
In order to determine the origin of the seep affecting the façade of Ad‐Deir, I collected sample bottles of water from a variety of cisterns, springs, and rainwater. These samples were kept in sealed amber bottles in the fridge to prevent evaporation. In the lab, chemical analysis was run on the water samples to determine the Delta O18 and Delta D content of the water samples. The results of these tests were graphed and compared with the hope that the results would show the origin of the seep itself. The chemical analysis was completed at BYU. In order to complete the structural analysis, I used a compass to take bearings on the fractures we encountered. These bearings are called strikes and can be graphed on a diagram called a Rose diagram to find out principle stress fields and stress directions. This can help determine the tectonic events that contributed to the formation of the rocks and formations that influenced the design of the city of Petra.
Upon returning to BYU, Dr. Harris and I were able to analyze the data I collected on the faults and fractures in Petra. We noticed that there post deposition, there was only one main event that caused all the fractures and faulting that created the striking geology of the Petra region. The event was the creation of the Dead Sea rift. I am still working on the full analysis of the region, but the data I collected so far is very promising. I also collected data on the earthquakes that destroyed Petra by looking at the orientation of fallen columns and the alterations of the arches.
The groundwater samples were tested for the amounts of Delta Oxygen 18. There is a standard amount of Oxygen 18 in the atmosphere, which is also present in rainwater. As water evaporates, the concentration of the oxygen isotopes grows. In testing the water from the seep and comparing it to water collected from cisterns, springs, and rainwater, we expected to see a trend that would show that the water from the seep originated from the dam to the left of the façade. Instead, we saw that although the concentrations changed in the cisterns to reflect evaporation as time went on, there was no change in the water of the seep. This trend was similar to the water samples that we collected from various springs around the Petra and Wadi Rum regions of Petra. We were not able to conclusively prove the source of the seep at this point in time, but our current hypothesis is that the seep is actually a spring that may date to ancient times. Further research is still required to prove the origins of the spring.
Due to the Ocra grant which I received, I was able to travel to Petra, Jordan along with a team of archaeologists and geologist as part of the BYU Ad‐Deir Monument and Plateau project. I collected water samples and data on the fractures and stress associated with the Ad‐Deir plateau. From the water samples, I was able to analyze the water from the Ad‐Deir monument seep and determine that the source of the flow is not from the dam as previously assumed, but is likely a spring. I also collected data on the geological structures of the plateau which has given me a greater understanding of how the Dead Sea rift shaped the landscape. This in turn affected how and where the Nabataean’s chose to place their buildings. Petra is a fascinating place that in not fully understood at this point and still has many mysteries left to uncover.