Fire and Ice: Living with Volcanoes, Earthquakes and Glaciers in Iceland
Iceland is a volcanically-hyperactive part of the Mid-Atlantic Ridge, where the North American and Eurasian plates diverge above a mantle plume. As such, Iceland provides a natural laboratory for detailed studies of process occur along mid-ocean ridges (MORs) where two-thirds of Earth’s crust is formed. Similar to MOR spreading centers, volcanic activity and seismogenic faulting are focused along discrete rift zones connected by transform faults. The rift zones are marked by active central volcanoes, high-temperature geothermal activity, and dike/fissure swarms that have produced the largest historic lava flows on Earth. Historic eruptions have posed major threats for both the local population and north Atlantic airline transportation. The rift zones occur in an en echelon array along a 50 km wide plate boundary zone that propagates N and S away from the center of the Iceland hot spot. Rift propagation results in migration of the seismically active, EW transform fault zones. Block rotations caused by changes in finite spreading along the plate boundary zone are associated with widespread, NS, rift-parallel, strike-slip faulting that may reactivate older zones of weakness created during spreading. The widespread faulting in the plate boundary zones helps maintain transmissive pathways for domestic hot water wells over much of Iceland. Glacial melt waters are exploited for hydroelectric power, but subglacial volcanoes periodically cause catastrophic glacial outburst floods (“jökulaups”), building a broad outwash plain and threatening vulnerable infrastructure. The Icelandic population has learned to live with both the benefits and hazards of this very active geological environment.
Dr. Page Quinton, Assistant Professor, SUNY Potsdam
Title: Carbon isotopes in shallow epicontinental seas: lessons from the Late Ordovician
· Introduction to the paleoclimatic and chemostratigraphic applications of bulk carbonate carbon isotopic values
· Discuss how sea level fluctuations might influence carbon isotopic trends in shallow epicontinental seas: 1) global to regional changes in carbon cycling vs. 2) regional to local changes in environmental conditions due to proximity to shoreline.
· How do we distinguish between these end member processes: a sedimentology, sequence stratigraphic, and geochemical approach?
· Introduction to Late Ordovician chemostratigraphy
· Trends and patterns observed in Laurentia’s epicontinental sea and what they can tell us about the relationship between sea level and carbon isotopic trends
· Future exploration and testing in Mississippian carbonates of Montana
Dr. Donald I Siegel, Syracuse University
“The Dismissal of Facts in Water-Related Decision Making: Root Causes and What to do About It”.
Water scientists no longer can assume that societal decisions on water, ranging from contamination to resource allocation, will be based on preponderance of scientific fact. Regional and social tribalism, single issues tied to ethics, and a fragmented digital media lead to bipartisan repudiation of science and the scientific method. Opposing sides of water (and other) scientific issues use identical play books to reduce the value of scientific facts; “cherry picking” data, smearing bearers of unwelcome scientific news, promoting obstructionist rhetoric, and not expressing true concerns. The scientific debate over methane concentrations in drinking water serves as a case in point. A possible way for scientists in water quality or quantity debates to ameliorate this sad state of affairs is to publicly respect and take the time understand the opposition to sound water science, thereby offering a chance for compromise in the future.
Dr. Esteban Gazel, Associate Professor Department of Earth and Atmospheric Sciences Cornell University.
"The rocks that joined the Americas: Is there a connection with climate and evolution of life?"
Earth’s crust is the life-sustaining interface between our planet’s deep interior and surface. Basaltic crusts similar to Earth’s oceanic crust characterize terrestrial planets in the solar system while the continental masses, areas of buoyant, thick silicic crust, are a unique characteristic of Earth. The continental crust is also enriched in incompatible elements (elements that separate from the mantle during partial melting) and although it is a volumetrically minor layer it plays a major role in the fractionation and storage of those elements. Therefore, understanding the processes responsible for the formation of continents is fundamental to reconstructing the evolution of our planet. Analyzing modern analogues where “juvenile” continental crust is forming can provide a better understanding of the formation of continental crust in the past. The evolution of the Central American Land-Bridge (CALB, Costa Rica and Panama) was used as a natural laboratory to answer this fundamental question. Geochemical and geophysical data support the evolution of the CALB into a young continent as a result of the interaction of Galapagos Hotspot tracks with this subduction system. A global survey of intra-oceanic arcs was conducted with the goal of identifying where magmas with continental crust signatures have been produced and what processes control the composition of the volcanic output. Finally, a new geochemical continental index was developed to quantitatively correlate geochemical composition with available average arc P-wave velocity, resulting in a strong correlation (r2=0.87) between those two parameters. Our work suggests that although the origin and evolution of continents may require many processes, melting of enriched oceanic crust and reaction of these melts with the mantle wedge in a subduction system will result in juvenile continental crust production, a process that was probably more common in the Archean than today. In Central America the production of “juvenile” continental crust culminated with the closure of the Panama Seaway ~15 to 3 Ma. This closure resulted in global change of ocean circulation, separated marine species, and allowed the exchange of fauna between the Americas, making the evolution of the CALB not only relevant to the understanding of geologic processes, but also had considerable impacts on evolution of life and climate on the planet.