St. Augustine, Trinidad & Tobago W.I. – June 16th, 2017 – Research scientist from The University of the West Indies Seismic Research Centre (UWI-SRC) in collaboration with scientists from Union College, Oberlin College and the Smithsonian Institute, U.S.A. are currently undertaking a two-week field class in Dominica. The interdisciplinary project aims to understand how different processes have shaped the Dominican landscape and history in the past and how they may manifest in the future. It is hoped that the island’s complicated explosive history will be better understood through geochronology and petrologic studies. The field class will build upon the work done by The UWI SRC by characterizing meteoric and hydrothermal waters, as well as volcanic gasses, from fumeroles to contribute to baseline monitoring of volcanic activity for use in detecting volcanic unrest. Attempts will be made to also study how the landscape has affected the settlement of people and the history of landslides.
The field class will be led by Dr Holli Frey (Union College), Dr Erouscilla Joseph (UWI-SRC), Dr Amanda Schmidt (Oberlin College) and Dr Laura Waters (Smithsonian Institute). The field class was advertised to students of the various American institutions and sixteen students will accompany the scientist. Student projects will be in the following fields: petrology, detrital geochronology, geochronology, physical volcanology, aqueous geochemistry, gas chemistry and landscape evolution. The second part of the field class will take place at Union College, U.S.A.
About Dominica geology
Dominica is a 750 km2 island of rugged topography and pristine rainforest which features nine volcanic centers that are <2.6 Ma in age. Dominica’s coastlines and interior valleys abound with thick ignimbrite deposits, composed of pumice clasts, rock fragments, and ash from solidified pyroclastic flows. There have been no documented explosive eruptions of large magnitude in Dominica in the last 20,000 years. The most recent activity involving magma was a lava dome collapse. Arcaheological investigations in the late 1970s unearthed clay pots beneath an ash horizon near the village of Soufrierre. Charcoal within the ash was dated at 450 ± 90 years B.P. Dominica’s most recent volcanic activity was several explosions of steam and ash violently ejected from hydrothermal vents. Phreatic eruptions ocurred in the Valley of Desolation in 1880 and 1997, covering an area <1 km2 with a thin (~2 cm) layer of ash. The Valley of Desolation is an active hydrothermal area and popular hiking destination of tourists. At the far end of the valley lies Boiling Lake, a 75 m volcanic lake that is is typically very hot (80-90 ˚C) and acidic (pH of 3-5). In addition to the older volcanic deposits and active hydrothermal areas, Dominica’s volcanic activity at present is recorded by earthquake swarms. The earthquakes are typically shallow (<5 km) and of fairly low magnitude (<4.0), often ocurring in rapid succession or swarms.
