ZZYZX, CA – This past weekend, Dr. Burmeister’s structural geology course travelled to the Mojave Desert. After a quick stop at Rainbow Basin to learn how to use topographic maps, air photos, and LiDAR datasets, we spent the rest of the weekend mapping the bedrock geology of the southern Salt Spring Hills. Not only does the Salt Spring Hills have a lot to offer in terms of structural relationships, but it was also the site of a series of (ultimately unsuccessful) gold mines during the mid to late 1800′s – the field area is packed with mineralized zones and abandoned mine workings.
This year we were fortunate to be joined by field trip co-leader Juan Contreras (Univ of Illinois, ’10). Juan is a geologist with Newmont Mining Corporation and is an expert in Carlin-type gold deposits. With Juan’s help, Dr. Burmeister re-tooled the existing Salt Spring Hills mapping exercise into a very realistic gold prospect evaluation. Within the scope of a mock contract from Newmont Mining Corp, Pacific students used their knowledge to collect the very same data that an economic geologist would collect on the job. Students were asked to map geologic structures and zones of potentially gold-bearing mineralization. They were given a budget of “12 million dollars” and asked to identify the targets for surface and subsurface (via RC drilling) assays that would be needed to begin a production phase at the Salt Spring Hills site. The results of their site assessments will be compiled into professional reports and presented to “bosses” from “Newmont Mining Corp” in the coming weeks… maybe we’ll all get rich!!!
While in the desert, the crew stayed at the Desert Studies Center (DSC) at Zzyzx, CA. The DSC is a research station maintained by the California State University system and is designed to support research and teaching in remote parts of the Mojave. The site has a long history – it was mineral bath retreat in the early to mid 1900′s before it was purchased by the CSU system. It offers wonderful cabins and dorm-style rooms, hot showers, and classroom spaces.
Students work on locating themselves in Rainbow Basin on topographic maps, air photos, and LiDAR datasets.
Group shot at sunset in Rainbow Basin. From L-R: Juan Contreras (Newmont Gold Corp), Christina Colburn (’13), Kat Rawhouser (’13), Dai Wilson (’14), Alicia Valenzuela (’13), Kaitlyn Blagg (’13), Brittany Klemm (’14), and Nikki Mainwaring (’13)
Brittany Klemm (’14) and Kaitlyn Blagg (’13) work on rock descriptions
Kat Rawhouser (’13) examines jointing in an exposure of granodiorite
Juan Contreras (Newmont Gold Corp) examines a rock for evidence of hydrothermal alteration
Garnet skarn (likely disseminated gold-bearing) from the Salt Spring Hills study area
A thick sequence of dark brown turbidite deposits in the Cambrian Wood Canyon Formation.
The Desert Studies Center at night
Nikki Mainwaring (’13, left) and Alicia Valenzuela (’13, right) work with Juan Contreras (Newmont Mining Corp) on geologic sketches
Kat Rawhouser (’13) and Brittany Klemm (’14) work together on a geologic sketch
Abandoned stone house at the Salt Spring Hills study area
Juan Contreras (Newmont Mining Corp) helps Nikki Mainwaring (’13) with her geologic mapping
Group photo at the Desert Studies Center, Zzyzx, CA
TULELAKE, CA – Students from the Geology of California (GEOS 61)course explored some of the most striking geologic features of northern California and southern Oregon on a late-September four-day field trip led by Dr. Kurtis Burmeister. The group started by learning about the formation and significance of Table Mountain near Oroville, then headed up the Feather River Valley to investigate the exposed metamorphic rocks and granodiorite plutons. During the second half of the day, the group examined how high-viscosity felsic lavas create stratovolcanoes that violently erupt into pyroclastic debris flows at Lassen Volcanic National Park, where the group camped for the night. On the second day, the caravan proceeded to Lava Beds National Monument to explore how the low-viscosity mafic lavas erupted from the Medicine Lake volcanic field to create not only broad shield volcanoes, but also lava tubes (into several of which the class intrepidly descended) and cinder cone volcanoes (one of which about half the class awoke before daybreak to ascend and watch the sunrise). The group camped at Lava Beds on the second and third nights of the trip, and, in between, paid a visit to Crater Lake National Park for a vivid look at just how catastrophic a high-viscosity felsic eruption can be. Jaw dropping in its beauty, Crater Lake is the remains of Mount Mazama, a stratovocano that completely obliterated itself in a cataclysmic eruption about 7,700 years ago. On the final day of the trip, the group was afforded spectacular views of Mount Shasta en route back to Stockton.
For the past five years, Dr. Burmeister has been accompanied on the trip by Dr. Ty Raterman (Department of Philosophy). This year, Drs. Burmeister and Raterman worked together to incorporate multidisciplinary exercises in which the students used their time in the field as a springboard for reflecting on the concept of nature and in turn on the relationship between naturalness and morality. The trip was further enhanced by the presence of Juan Contreras and Andrew Ostendorf, economic geologists from Newmont Mining Corporation. In addition to talking with students about some of the significant professional opportunities available to recent graduates with a B.S. in Geology, Juan and Andrew shared their knowledge about how the same igneous processes that lead to volcanic eruptions can lead to the concentration of economically considerable deposits of gold, silver, and copper ores. Teaching assistants Nikki Mainwaring, Brittany Klemm, and Christina Colburn were an immense help with driving and campsite logistics. With gorgeous weather, gourmet meals including Japanese curried vegetables over rice and berry cobblers cooked in a dutch oven for dessert, a warm campfire each night, and not a single wrong turn by the caravan’s lead vehicle, the trip could hardly have gone better!
Andrew and Juan explain how groundwater heated by magma chambers can lead to the accumulation of economically significant ore deposits
Andrew explains the process of mining for gold underground
The Fall 2012 GEOS 61 crew at Crater Lake National Park
Dr. Raterman talks with the students about the relationship between naturalness and morality at Vidae Falls, Crater Lake National Park
The true colors always seem to come out at Pumice Point, Crater Lake NP
Students consider the concept of nature atop a volcanic vent at Lava Beds National Monument