NWT RESEARCH DATABASE

Tags: physical sciences, climate change, fossils, paleoclimatology, carbon, isotopes

Objective(s): To measure tree rings for carbon and oxygen isotopes to determine past climate; to collect sand samples to date the layers which contain the wood and evidence of faulting; to map the faults and tilting of the layers of the sands that were originally deposited during Pliocene; and, to collect fossil material (leaves, fossil insects, fossil vertebrates).

Project Description: The objectives of this research are to: 1) collect pieces of wood to measure tree rings and carbon and oxygen isotopes to determine past climate (mainly average summer temperature); 2) collect sand samples to date the layers which contain the wood and evidence of faulting, so the team can date they can be dated to show how old the wood and faults may be; 3) map the faults and tilting of the layers of the sands that were originally deposited during Pliocene; and, 4) collect fossil material (leaves, fossil insects, fossil vertebrates). The research team will collect wood by cutting disks of the least altered fossil wood, using a saw. The research team will collect sand by using a shovel and small trowel, and collect approximately a gallon-size ziplock bag full (approximately 2 kg of sand). The sand will be sent to Dalhousie University and processed to extract isotopes from quartz that will be measured to determine when the sand layers were deposited (approximately 3 million years ago). The team map and determine the fault types by using a compass, topography maps, measuring tape, laser range finder and observing how different layers of sand have moved relative to each other. Fossil material will be collected (to be shipped to the Canadian Museum of Nature) by documenting and photographing the location, and placing each fragment or multiple fragments into bags or boxes in accordance with standard protocol. Most of the time will be spent walking along steep escarpments where original layers are exposed naturally, to search for wood and fossils, and quartz sand for dating. This research will help provide information about the increase in erosion rates on western Arctic islands. That erosion may fill currently used drinking water reservoirs, may change streams, and may fill shallow harbours which will change access to some communities. This research also will contribute to better understanding if there is an earthquake risk in the region. The research team have recently identified large faults which offset recent sediments on Prince Patrick Island, so this summer the team hope to measure the offset and verify the type of faults. If in 2017 the research team document a reasonable earthquake risk to the hamlets of Holman and Sachs Harbour, in 2018 the team will invite residents to participate in sharing any information about the timing and extent of ground shaking from an earthquake they may have experienced. The research team will provide a summary of the research findings in English and Inuinnaqtun. The team will produce a publication with more detailed findings, published for non-specialist audience. If there appears to be a reasonable earthquake risk, the research team would like to inform the communities of Ulukhaktok and Sachs Harbour what the risks may be and how they could minimize any damage. If members of the communities are interested the team would like to learn if any of them have felt an earthquake on Banks or Victoria Islands. The fieldwork for this study will be conducted from July 12, to August 2, 2017.