Geology Open Night

Geology Open night lectures are usually on topics in the geosciences related to the current research of the faculty, staff and students at SUNY Stony Brook. These presentations are intended for:

• those interested in new developments in the sciences

• earth science high school students and teachers

• undergraduate and graduate students in geosciences

• professional geologists

 Water on early Mars: role of giant impact basins

Prof. Deanne Rogers

7:30  PM Friday February 22, 2013
ESS 001

The present day climate of Mars is characterized by cold, arid conditions, with no liquid water present at the surface.  However, ancient valleys observed in the oldest terrains suggest that the Martian climate was once conducive to fluvial activity, at least temporarily. Volcanic activity can temporarily affect planetary climate by bringing heat and gases from the interior to the surface. But the timing, style and magnitude of volcanic activity during early Martian history has not been well understood because of extensive cratering and degradation, which has erased much of the surface record of this activity. High-resolution instruments now in orbit around Mars yield new observations of likely volcanic materials.  I will discuss these new observations and the possibility that giant impact basins enabled magmas, which likely formed below a thick crust, to ascend to the surface.  Giant impact basin formation may have played a role in Martian climate that has perhaps been underestimated in the past.

Prof. Rogers joined the Stony Brook Geosciences department in 2007. Her research group focuses on using remote sensing techniques and infrared laboratory spectroscopy to investigate earth and planetary surface processes. Rogers is a NASA Early Career Fellow and was involved in the Mars Odyssey and Mars Exploration Rover missions.  She teaches Natural Hazards and Remote Sensing.

 Fate of Nitrogen in Groundwater Entering
Stony Brook and Port Jefferson Harbors

Gilbert N. Hanson, Caitlin Young and Josephine Durand
7:30  PM Friday April 26, 2013
ESS 001

Nitrates in marine waters surrounding Long Island are a serious problem because they encourage the growth of algae leading to, for example, red tide, and can result in low oxygen conditions (hypoxia) in bottom waters which is deadly to marine life. While the amount of nitrate produced by sewage treatment plants is well known, the amount of nitrate associated with groundwater (from fertilizer and septic tank sewage) that enters our surrounding marine waters is not well known. This upwelling of groundwater below coastal waters which mixes with the overlying seawater is known as submarine groundwater discharge.

To determine the amounts of nitrate that may be entering our surrounding marine water we are investigating the fate of nitrogen in groundwater entering Stony Brook and Port Jefferson Harbors by submarine groundwater discharge. The amount of nitrogen that enters the harbors by submarine groundwater discharge is a function of the nitrate concentration of the groundwater, the flux of submarine groundwater discharge into the harbors and the amount of denitrification that occurs as the groundwater mixes with the seawater at the groundwater-seawater interface. The extent of submarine groundwater discharge in these harbors has been evaluated by a number of techniques including electrical resistivity and seepage meter measurements. Our analyses show that there is little denitrification of nitrate in the groundwater before mixing with seawater. If the groundwater upwells where the bottom sediments are sand and gravel, there is little denitrification in the mixing zone. If the groundwater wells up where the bottom sediments are organic-rich muck there is almost complete denitrification. However, because the muck is essentially impermeable, most of the submarine groundwater discharge is at the harbor floor dominated by sands and gravels. As a result much of the nitrate in groundwater, which may have concentrations as high as 10 mg/l, enters these harbors where it mixes with the overlying seawater which has a much lower nitrate content.

 Gilbert N. Hanson is a Distinguished Service Professor in the Department of Geosciences. Caitlin Young is a Ph.D. student in the Department of Geosciences who is studying the geochemistry of the groundwater and marine water in the mixing zone to evaluate what is happening to nitrogen. Josephine Durand is a Ph.D. student in the Department of Geosciences who is using geophysics to evaluate the extents and amounts of freshwater that are entering the harbors.

  Exploring Mars with Curiosity

Prof. Scott McLennan
and the
MSL Science Team
7:30  PM Friday May 17, 2013
ESS 001

The 2011 Mars Science Laboratory Curiosity rover landed at Bradbury Landing in Gale Crater, Mars on August 6, 2012 (UTC) using a new and innovative entry, descent and landing (EDL) system. Its purpose is to explore and quantitatively assess a region within Gale Crater as a potential habitat for past or present life. At the time of this lecture, Curiosity will have been exploring Gale Crater for over 9 months – or more than one-third of its full Mars-year prime mission. With a mass of about one metric ton, Curiosity is, by far, the most capable robot ever sent to another planetary surface. In addition to a variety of remote sensing and surface contact instruments, it carries a sophisticated internal laboratory, fed by an atmospheric inlet valve, soil scoop and rock drill, that is capable of determining mineralogy and the chemical and isotopic compositions of atmosphere, rocks and soils. This lecture will review the capabilities of the Curiosity rover and describe its major scientific findings to date.