Zelalem Bedaso

Dikika Paleoanthropological Site, Afar, Ethiopia: Dikika is one of the most famous paleoanthropological sites in the Afar region of Ethiopia renowned for its wealth of hominid and other mammalian fossils. Dikika is part of the greater Afar sedimentary basin situated in the Ethiopian Rift Valley, which is located about 300 km northeast of Addis Ababa, capital of Ethiopia. Sediments exposed in Dikika area are nearly continuous sequence spanning the period between 3.8 Ma and 0.15 Ma (Wynn et al., 2006). Dikika is particularly known for the discovery of a nearly complete fossilized remains of a 3.3 million-year-old Australopithecus afarensis 3-years-old child. My research at Dikika is particularly focused on establishing the mid-Pliocene paleoenvironmental and Paleoclimatic framework of the site and reconstructs the paleolandscape where Australopithecus occupied.

Galili Paleoanthropological Site, Afar, Ethiopia: Galili Paleoanthropological Research area is the southernmost Pliocene hominid site in the Afar depression, Ethiopia. Since 2000, more than 1500 fossil specimens of more than 50 vertebrate taxa were collected and hominids are represented by several teeth (Macciarelli et al., 2004) and a femur of Australopithecus sp.. The mount Galili Formation is dated between ~5.3 Ma and ~2.3 Ma. My role at Galili is establishing paleoenvironmental context of the mount Galili formation using isotopic proxy record of fossilized tooth enamel for the time interval relevant to Ardipithecus ramidus, and Australopithecus.

Water Isotopes (hydrogen and oxygen) in Ethiopian Precipitation: Spatial and temporal water isotopic data in modern precipitation contribute crucial information about global climate change in the past and today. The global distribution of isotopes in modern precipitation in the last few decades are monitored by the International Atomic Energy Agency and the World Meteorological Organization Global Network for Isotopes in Precipitation (GNIP) database (Edwards et al., 19196). In Ethiopia, however, there is only one long-term monthly collection station in Addis Ababa. But water isotope is known to vary both in space and time, so to document these variations, understand source of moisture and establish interpretive framework of oxygen isotopes for the paleo archives. Dr. Naomi Levin (Johns Hopkins University) and myself in collaboration with the National Meteorological Agency of Ethiopia established four precipitation collection stations in the Ethiopian highlands and collected precipitation samples on daily, weekly and monthly time intervals.

Andrea Kozoil

Massachusetts: Research on potential high-pressure schists and gneisses.

Allen McGrew

Nevada: The goal of the Keck Nevada Project is to document the kinematics and thermal evolution of deep-crustal rocks exposed during exhumation of the northern half of the Ruby Mountains (RM)-East Humboldt Range (EHR)-Wood Hills (WH) metamorphic core complex. Although the RM-EHR-WH is widely recognized as a classic metamorphic core complex, debate persist about the timing and kinematics of crustal extension. Students conduct detailed geologic mapping and collect low-temperature thermochronologic, sedimentologic, and structural data to better characterize the exhumation of the RM-EHR-WH core complex. These results are integrated to test competing models for the structural development of the complex, in order to better understand mid-to-lower-crustal deformation.

Our students are engaged:

Sustainability of Ground Water in Dayton, Ohio

Amber Johnson was a senior undergraduate student in the Department of Geology and Environmental Geosciences working under research advisor Dr. Zelalem Bedaso. She worked on a summer 2016 water isotope project entitled “Assessing the impact of climate change on the sustainability of groundwater resource in the Dayton region – an interdisciplinary approach” with funding from the Hanley Sustainability Institute (HSI).

The purpose of the project was to use a multi-disciplinary approach to understand seasonality in the isotopic composition of precipitation and estimate seasonal contribution of precipitation for groundwater recharge and determine the future sustainability of groundwater in the Miami Valley. The project was a co-effort with Dr. Shuang-Ye Wu and her undergraduate research student, Colin McTighe. Dr. Wu and her student worked on the climate-modeling component of the project to understand and predict future groundwater resource conditions under the unprecedented climate change our planet is facing today.

In addition the ongoing, three year precipitation collection on the roof of Fitz Hall on a daily, weekly, and monthly basis, water samples were collected throughout the Miami Valley for isotopic study. In June, 2016, surface water was collected from streams that feed into the Great Miami and Mad Rivers, and with the help of Duncan Upp, supervisor of the Miami and Mad River well fields, more than 25 groundwater samples were collected. In July 2016, additional groundwater samples were collected from four monitoring wells with the help of Mike Ekberg, Manager of water monitoring, and Zach Smith from the Miami Conservancy District (MDC).

The water samples were sent to the University of Utha stable isotope facility for isotopic analysis. The isotopic ratios of hydrogen and oxygen were shown to be seasonally distinct, and using mass balance, the summer and winter recharge contribution to Dayton groundwater were calculated. Determining this contribution is important because it can be implemented for decision-making and water resource planning.

If the contribution of each season to groundwater recharge can be determined, plans can be made for a situation where a source of precipitation is cut off, or during a season with low precipitation. Using this prediction, water resources may be properly allocated in the most sustainable way for each season.