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SDAG Monthly Meeting
Wednesday, February 15, 2017

Location: Phil's Barbecue Event Center, Point Loma
3750 Sports Arena Boulevard
San Diego, 92110

Phil's Barbecue Event Center is located in the back of the shopping center - behind the regular restaurant along the street. Across the Parking Lot, Behind Phil's BBQ Restaurant.
happy hour
5:30pm -
Social hour  
Cash Bar.

Menu: Pulled Pork and Tri-Tip Sandwiches or Veggie Burger. Cash bar.
6:30pm -

Cost: $40.00 for non-members, $35.00 for members, $20.00 for students. if pre-registered by the deadline, $5 extra if you did not make a reservation. Click the SDAG member checkbox on the reservation form if you are a member.

Reservations: Make your reservation online by clicking the button below no later than NOON, Monday, February 13. RESERVATIONS CANNOT BE ACCEPTED AFTER Monday at noon. Late reservations/cancellations are preferred over walk-ins or no-shows. Fees payable at the meeting or pre-pay with PayPal.
As a new payment option, there will be a phone credit card reader at the meeting.

If you are a current SDAG member and are not getting e-mail announcements,
make sure the SDAG secretary has your correct e-mail address.

7:30pm -

Speakers: N. Scott Rugh, Dr. Geoff Cromwell, & Wes Danskin

"Use of fossils, cuttings, and geophysical logs obtained from deep wells to develop the first 3D geologic model of the San Diego-Tijuana area, USA and Mexico"


The San Diego Hydrogeology project is a cooperative effort by the United States Geological Survey (USGS) and local water agencies to determine the quantity and quality of groundwater in the San Diego-Tijuana area. Historically, most groundwater in the San Diego area has been extracted from the Plio-Pleistocene San Diego Formation and the overlying Quaternary deposits. In order to understand how groundwater flows through these units, additional information is needed to quantify the location and thickness of these units and the underlying sedimentary formations. The first step was to develop a comprehensive three-dimensional (3D) geologic framework model, in particular using data collected from 12 multiple-depth, monitoring-well sites, which were installed by the USGS over the last 20 years. Drill cuttings were collected at each site, which provided fossil and lithologic data that are heavily relied on in developing the geologic model.

Fossil identification and lithologic descriptions of drill cuttings from the USGS well sites enabled evaluation of the subsurface extent and thickness of local geologic units. Nine of the 12 well sites contain sandstone with common-to-abundant invertebrate fossil shell fragments, ranging in size from .05 to 0.5 inches, and ranging in depth from 20 to 1,600 feet below land surface. Sediment identified as the San Diego Formation, by the presence of several indicator species, was found in the nine wells; fossil species unique to younger Quaternary deposits are common in at least one well. The geographic distribution of the USGS well sites and the prevalence of fossils at depth allows for a robust analysis of the upper and lower members of the San Diego Formation. The lower member, deposited in sea-water between 100 and 300 feet deep, is identified in all nine wells and ranges in thickness from 380 to 1,160 feet. The upper member, deposited primarily at depths less than 100 feet, is more limited in lateral extent; it is identified in only two northern wells where its thickness is 70 and 180 feet.

The vertical characterization of geologic units was integral to development of the first 3D geologic model of the San Diego-Tijuana area. In total, eight geologic units and 10 fault systems are defined in the model, which extends roughly north-south from La Jolla, California, to Tijuana, Mexico; and east-west from El Cajon, California, to the offshore Coronado Bank. The geologic model provides new insight into the geologic history and characteristics of the San Diego-Tijuana area and will serve as a useful tool for geologic and hydrologic investigations.

Mr. N. Scott Rugh
N. Scott Rugh, is an independent invertebrate paleontologist who specializes in Neogene invertebrate fossils of southern California. His more than 20 years of experience as a paleontologist includes identification of the late Miocene invertebrate fossil species of the Stout Research Center, including the Susan M. Kidwell collection of the University of Chicago, and as collections manager of the invertebrate fossil collections of the San Diego Natural History Museum for 13 years. As additional experience, he works as an invertebrate paleontology specialist who works with various southern California archaeology and paleontology consulting companies. Mr. Rugh earned his M.S. degree in Biology with an emphasis in Ecology at San Diego State University.

Dr. Geoff Cromwell
Geoff Cromwell is a geologist with the U.S. Geological Survey in San Diego, California. He received his PhD in Earth Sciences from Scripps Institution of Oceanography at U.C. San Diego in 2014, and taught at Occidental College in Los Angeles before joining the USGS full time in 2015. Geoff specializes in developing regional hydrogeologic framework models that define aquifer characteristics, and are used with numerical groundwater flow models. He also has a background in paleomagnetism, with a focus on estimating the intensity of the ancient geomagnetic field.

Mr. Wes Danskin
Wes Danskin is a senior Research Hydrologist for the United States Geological Survey, living and working mostly in southern California. For the past 40 years, Mr. Danskin has applied and taught how to apply simulation and optimization techniques to complex, real-world, water-management problems. For the past 15 years, Mr. Danskin has led the USGS San Diego Hydrogeology project, which is providing the foundational geologic and hydrologic information in the San Diego-Tijuana area. Results of this study are being used to develop additional local water supplies, in particular brackish groundwater that is being desalinated and distributed for municipal use.

Upcoming SDAG meetings - 2017

March 22 (4th Wed.): Understanding the Licensure Laws and Responsibilities of the Licensee & Student Presentations

April 19: John Minch - The Greater Hanshin (Kobi) Earthquake

May 17: John Wallace and Pat Shires - Sycamore-Ranchito Landslide - Santa Barbara

Meetings are usually scheduled for the 3rd Wednesday evening of the month. Meeting information on this website is normally updated the second week of the month.

If you have any information, announcements, ads or suggestions for an upcoming newsletter, please submit it to Ken Haase, (2017 SDAG Secretary). Any news regarding upcoming events that may be of interest to the Association or news of your business can be submitted. The submittal deadline for the next SDAG newsletter is the last Friday of the month.
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