11-15-2014 Gary Green: Ecology of the Salish Sea

About the Talk

Geology beneath the Salish Sea and how it controls its ecology

 On Saturday, Nov. 15th, you’ll have a chance to see how the geology beneath the Salish Sea controls its ecology. The complex geology beneath the Salish Sea results from a series of long geologic processes including, but not limited to, plate collision and subduction, glaciation, and sea level changes. The sculptured landscapes and seascapes created by these processes provide unique benthic habitats for a variety of organisms critical to keeping the inland sea of the Salish both viable and healthy.

Many of the habitats are ephemeral, constantly being altered through oceanographic and tectonic activities. For example, dynamic bedforms created by strong tidal currents provide habitats for foraging fish, such as the Pacific sand lance, whereas rock rubble shaken from the flanks of islands by earthquakes forms habitat for rockfish and lingcod. Deep-sea sponge reefs trap sediment and provide relief on an otherwise flat seafloor that in turn provide shelter for fish and other organisms from strong seafloor currents and refuge from predation. Seafloor exposures of bedrock and basement rocks provide hard substrate for encrusting and sessile organisms that provide food and shelter to epifauna and fish, while organic and fine-grain clastic sediments fill bays and sounds, creating a substrate for eelgrass and other shallow water vegetation that provide recruitment habitats for a multitude of organisms. All of these geologic processes have been studied in detail with the use of up-to-date seafloor imaging technology that reveals the seafloor in great detail. These images and the conclusions derived from them will be presented in an illustrated hour-long talk sponsored by the Jefferson Land Trust’s Geology Group.

About the Speaker

Gary Greene is currently the Director of the SeaDoc Tombolo Mapping Lab on Orcas Island, WA.  He also holds positions at the Friday Harbor Marine Laboratories (UW) and the Moss Landing Marine Laboratories (SJSU).  Dr. Greene obtained his Ph.D. in Marine Geology from Stanford University in 1977, an M.Sc. in Geophysics from San Jose State University, and a B.Sc. in Paleontology from Long Beach State University.  Since then has had a long and varied career as a professor, research scientist, and manager.

01-10-2015 Ray Pestrong: Earth Art

About the Talk

Earth as Art

In his 2012 book, “The Sciences and the Arts,” Chemist Harold Cassidy draws parallels between the way artists and scientists view their worlds. He states that “there is no subject that is unfit for the probing insight of the artist, nor is there anything unsuitable for the scientist to examine.”

The premise of Dr. Pestrong’s presentation is that Art is central to the Earth, both figuratively and literally. If you cover the first and last letters of the word “Earth”, there is “art”. This is a symbolic indication of how integral Art is to the Earth and how aspects of the Arts enhance our understanding of Earth Sciences.

A 21st-century paradigm is emerging in which the integration of different fields of knowledge is seen as a necessary goal. When connections are established among otherwise disparate bits of data, more universal theorems and deeper understanding result. Our speaker’s goals, in this context, are to show how aspects of the Arts may be used to generate interest and gain insights into how the Earth works and to demonstrate how logic is not restricted solely to the scientist and that intuition is not the sole realm of the artist.

This hour-long program has been shown all across the United State to a broad spectrum of audiences. It was developed as a teaching tool for introductory geology courses, but its wide acceptance is an indication of the profound interest we have in the physical environment. Like the world it reflects, Earth Art is constantly changing as new relationships become apparent; as you’ll see, Earth Art comes in many forms.

About the Speaker

Ray Pestrong is an Emeritus Professor of Geology in the Department of Earth & Climate Sciences at San Francisco State University. For 44 years, he has taught geomorphology and engineering geology, as well as numerous general education courses in introductory geology. Dr. Pestrong has written college texts and scientific articles and has produced geologic videos. For the past 22 years, Ray has led rafting trips on the Colorado River through the Grand Canyon. What he loves most is teaching and the exciting interactions possible through that venture.

06-26-2015 Hank Schasse: Geology of Port Townsend

GEOLOGY OF PORT TOWNSEND 
Lecture: Friday, June 26 @ 3:30 pm
Field Trip: Saturday, June 27 @ 9 am

About the Talk

Hank Schasse of Olympia, WA, will discuss the geology of the Port Townsend region.  The one-hour lecture will be at the Jefferson County Public Library in Port Hadlock starting at 3:30 pm on Friday, June 26th.  Seating is limited to about 80 persons.  There is no cost for the lecture, but a $5 donation would be appreciated to offset costs associated with travel and other support for the speaker and event.

Port Townsend sits at the northern end of the Quimper Peninsula, a promontory that juts northeast into the Salish Sea. The peninsula is underlain by Tertiary rocks (~50 to ~25 million years old, here) that are composed of locally erupted oceanic basalts and associated conglomerates, and marine sandstones, other conglomerates, and intervening shales. These rocks have been uplifted, tilted, and faulted through progressive onshore deformation associated with Cascadia subduction and northern transport of crustal rocks. With the onset of continental glaciation about 2 million years ago, tongues of ice as much as 4,000 ft thick flowed southward from British Columbia and plowed across the topography as far south as Olympia and west to the coast.  As many as a dozen separate glaciations occurred, but only the latest advance (the Vashon, ~20,000 to 12,000 years ago) has left a clear record of its movement and deposits.

Hank will illustrate many of these relations during his talk, based on his 2004-05 mapping of the Port Townsend and Port Hadlock areas.  Come prepared to ask general questions about your favorite areas and outcrops.

 

 

 

 

 

Field trip included a walk along Discovery Bay beach to fossil bearing outcrop.

 

 

Field trip included walk and discussions of glacial stratigraphy along the beach at Fort Worden.

 

 

 

About the Speaker

Hank Schasse as a geologist for the Washington State Department of Natural Resources, Geology Division spent much of his career mapping the geology of Washington.  Hank is now retired but still loves to share his knowledge of the area of Port Townsend.