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SDAG Monthly Meeting and Joint Meeting with SCGS
Tuesday, January 15, 2019

Location: Green Dragon Tavern and Museum
6115 Paseo del Norte
Carlsbad, CA 92011
Tel: 760.918.2421

Take I5 to Palomar Airport Rd east, to right turn (south) on Paseo del Norte, to right turn at second driveway to Green Dragon Tavern and Museum, just past Taco Bell, north of Motel 6.
happy hour
5:30pm -
Social hour  

Menu: Herb Grilled Chicken Breast, Vegetarian Cheese Ravioli, Classic Caesar Salad, Vegetable Medley, Garlic Mashed Potatoes, Bread Rolls, Cheesecake.
6:00pm -

Cost: $45.00 for non-members, $40.00 for members, $25.00 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, Friday, January 11
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.

7:00pm - 8:00pm

"A Landscape Altered: The Explosive End to Kïlauea's Summit Lava Lake and the Lower East Rift Zone Eruption of 2018"

Speaker: Dr. Ken Hudnut, Matt Burgess, Diane Murbach

Abstract: Kïlauea is a basaltic shield volcano located on the Island of Hawai´i characterized by a summit caldera and two radiating rift zones. Currently ranked by the USGS as the number one threat for U.S. volcanoes, along with Etna and Piton de la Fournaise (Reunion Island), it ranks among the world's most active volcanoes and is often considered the most active volcano on Earth. Kïlauea, which is built on the east flank of the massive Mauna Loa volcano, has been Hawaii's most active volcano during historical time. Once thought to be a mere satellite of its giant neighbor, research over the past few decades shows that Kïlauea has its own magma plumbing system, extending to the surface from more than 37 miles deep in the mantle. It lies along the Kea trend of magmatic composition, chemically similar to Mauna Kea, Kohala, Haleakalá (Maui), West Maui and east Moloka'i and chemically distinct from the sub-parallel Loa trend volcanoes: Lô'ihi, Mauna Loa, Hualálai, Máhukona, Kaho'olawe, Lána'i, west Moloka'i and Ko'olau (O'ahu) .

Eruptions are prominent in Polynesian legends as the volcano is home to the deity Pele, who is revered in Hawaiian culture; and though written documentation only extends back to 1820, it records frequent summit and flank lava flow eruptions interspersed with periods of long-term lava lake activity3. The 1.9 x 3.1 mile caldera was formed in several stages, with the most recent caldera forming period lasting about 300 years between 1500 and 1790 CE. The penultimate lava lake within the Halema'uma'u crater in the summit caldera, persisted for about 100 years, ending with explosive eruptions in 1924 when an intrusion entered the lower East Rift Zone. Since 1952 there have been 34 eruptions on the volcano3. Eruptions have also originated from the >32 mile long East and >19 mile long Southwest Rift Zones, both of which extend to the sea from the volcano's summit. About 90% of the surface of the volcano is made up of lava flows less than 1100 years old and 70% of the volcano's surface is younger than 600 years old. A long-term eruption from the Pu'u'Ô"ö vent on the East Rift Zone that began in 1983 produced lava flows covering more than 39 square miles of land, inundating the community of Kalapana, destroying nearly 200 houses (before 2018) and adding new coastline to the island.

In the spring and summer of 2018 Kïlauea underwent drastic changes in its eruption, forever altering the once familiar landscapes. The Pu'u'Ô"ö vent collapsed on April 30 and magma migrated down rift. A magnitude 6.9 earthquake occurred on the volcano's south flank on May 4th and ~60,000 earthquakes occurred on the volcano between April 30 and August 4. Fissures formed in the populated Leilani Estates area of the lower East Rift Zone, eventually erupting ~1 billion cubic yards of lava. 716 dwellings were destroyed as 13.7 square miles of land was inundated by lava and 875 acres of new land was created by ocean entries. The lava lake in Halema'uma'u, present in the Overlook vent since 2008 and overflowing onto the floor of the crater between April 22 and 28, had completely drained by May 10th, a decline of almost 1000 ft. Beginning on May 16 the summit vent became the site of explosive events that sent ash as high as 30,000 ft. On May 29 the caldera around Halema'uma'u began to subside and near-daily summit collapse events continued until August 2nd, with each event releasing energy equivalent to that of a ~ magnitude 5 earthquake. When the dust had settled the partial collapse of the caldera had increased the area of Halema'uma'u by ~1 billion cubic yards and maximum subsidence in the caldera was over 1,600 ft. By August 17th eruption of lava from fissure 8 had stopped and the ocean entries were no longer active by August 21. By September 4th when lava was no longer visible in the fissure 8 spatter cone, Kïlauea's largest eruption in at least 200 years was at least temporarily over.

1 Montgomery-Brown, Emily K., Poland, Michael P. , and Miklius, Asta, 2015, Delicate Balance of Magmatic-Tectonic Interaction at Kïlauea Volcano, Hawai'i, Revealed from Slow Slip Events, in Hawaiian Volcanoes: From Source to Surface, Geophysical Monograph 208. First Edition. Edited by Rebecca Carey, Valérie Cayol, Michael Poland, and Dominique Weis. © 2015 American Geophysical Union.

2 Ewert, John W., Diefenbach, Angela K., Ramsey, David W., 2018, 2018 update to the U.S. Geological Survey national volcanic threat assessment, U.S. Geological Survey Scientific Investigations Report 2018-5140,

3 USGS Hawaiian Volcano Observatory, Kïlauea summary,ïlauea/, accessed 11/4/2018

4 Clague, David A., and Sherrod, David R., 2014, Growth and Degradation of Hawaiian Volcanoes, Chapter 3 in: Characteristics of Hawaiian volcanoes: U.S. Geological Survey Professional Paper 1801, 429 p., Poland, M.P., Takahashi, T.J., and Landowski, C.M., eds.,

5 Swanson, Donald A., Rose, Timothy R., Fiske, Richard S., McGeehin, John P., 2011, Keanakáko'i Tephra produced by 300 years of explosive eruptions following collapse of Kïlauea's caldera in about 1500 CE, Journal of Volcanology and Geothermal Research, 215-216 (2012) 8–25

6 Wright, Thomas L., Klein, Fred W., Two hundred years of magma transport and storage at Kïlauea Volcano, Hawai'i, 1790-2008, U.S. Geological Survey Professional Paper 1806, 258 pp.,

7 Smithsonian Institution Global Volcanism Program, Kïlauea summary,, accessed 11/4/2018

8 USGS Hawaiian Volcano Observatory, September 2018, Preliminary summary of Kïlauea Volcano's 2018 lower East Rift Zone eruption and summit collapse,

Link to copy of their recently published Kïlauea paper:"

Dr. Ken Hudnut has studied earthquakes as a geophysicist for the U. S. Geological Survey (USGS) in Pasadena since 1992. He recently led large team efforts to develop the HayWired Earthquake Scenario, as well as to obtain high-resolution topographic data using helicopter-mounted lidar to assess the eruption of Kïlauea volcano. To help understand the San Andreas Fault system and the behavior of faults in general, he has studied earthquakes worldwide using satellite & airborne imagery along with field work to provide ground truth. Recently, he received awards for distinguished service and leadership from the American Geophysical Union and for meritorious service from the U.S. Department of the Interior. He is a Visiting Associate in Geophysics at Caltech and a Lecturer (on engineering geology) in Civil & Environmental Engineering at UCLA. He received his Ph.D. from Columbia in 1989, and his A.B. (high honors) from Dartmouth in 1983.

Matt Burgess was the seismic analyst for the USGS Hawaiian Volcano Observatory from 2013 - April 2018. On May 4th, 2018 he was called into emergency service for the USGS response to the eruption of Kïlauea volcano. For the following five weeks he stood watch 12 -15 hours per day over streaming real time geophysical data, providing situational awareness on the eruption from seismic, infrasound, deformation and atmospheric radar reflections off the tops of ash columns to Observatory staff in the field and Emergency Operations Command from his home in San Diego. He has a MS in Geological Sciences from SDSU (2008) and has previously worked for the USGS California Water Science Center, San Diego Natural History Museum as well as on geophysics research projects at Mt. St. Helens, Long Valley Caldera, volcan Villarrica in Chile and the Alpine Fault, New Zealand. He is currently parenting full time, a volunteer research associate with the Hawaiian Volcano Observatory studying patterns of seismicity on Kïlauea and Mauna Loa, volunteering with the Guza lab coastal studies LiDAR group at Scripps Institution of Oceanography, and looking for meaningful long term employment in the geological sciences in San Diego.

Diane Murbach is a Certified Engineering Geologist (CEG) with 35 years of experience and registered in the States of California, Oregon, Washington and Arizona. She is a principal engineering geologist working as a co-owner of Murbach Geotech (MG) with her husband Monte Murbach. Diane received a B.S. degree from Eastern Washington University and an M.S. degree from San Diego State University in Geology. Diane's volunteer work for geological societies includes being a past President for the San Diego Association of Geologists (SDAG), and the South Coast Geological Society (SCGS). She currently serves as Secretary on the Board of Directors for the San Diego Geological Society, Inc., and chair for the Earth Science working group updating the San Diego Tijuana Earthquake Planning Scenario. Diane's background with volcanoes began in 1979 with Monte when both attended a two week Geology of Hawaii class on the Big Island. Six months later both were on another geology class next to Mount St. Helens in the state of Washington when this stratovolcano erupted. Diane and Monte have been chasing volcanoes and visiting all the Hawaiian Islands for the past 40 years.

Upcoming SDAG meetings - 2019

February 20, Marina Village: Vic Camp - Yellowstone Hotspot

March: TBD

April: TBD

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 Heather Reynolds, (2019 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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