Julie Donnelly-Nolan is a research geologist at the U. S. Geological Survey in Menlo Park CA. She does field mapping of volcanoes and collaborates with argon chronologists, paleomagnetists, and petrologists in order to understand potential hazards presented by the volcanoes.
She has spent two decades doing detailed geologic mapping at Newberry Volcano with the goal of unraveling its history and understanding its potential hazards. She also worked for many years at Medicine Lake volcano in N. CA (https://pubs.usgs.gov/sim/2927/). Prior to that she did her U.C. Berkeley PhD thesis on the Clear Lake Volcanic Field in the CA Coast Ranges.
Education and Certifications
PhD, UC Berkeley
Affiliations and Memberships*
American Geophysical Union (AGU)
Geologic Society of America (GSA)
International Association of Volcanology and Chemistry of the Earth's Interior (IAVCEI)
Science and Products
Database for the Geologic Map and Structure Sections of the Clear Lake Volcanics, Northern California
Hazard boundaries for the volcanic hazard assessment of Medicine Lake volcano, California
Newberry Volcano's youngest lava flows
Geologic map of Medicine Lake volcano, northern California
Geologic field-trip guide to Medicine Lake Volcano, northern California, including Lava Beds National Monument
Overview for geologic field-trip guides to Mount Mazama, Crater Lake Caldera, and Newberry Volcano, Oregon
Overview for geologic field-trip guides to volcanoes of the Cascades Arc in northern California
Field-trip guide to the geologic highlights of Newberry Volcano, Oregon
Late Holocene volcanism at Medicine Lake Volcano, northern California Cascades
Straddling the tholeiitic/calc-alkaline transition: The effects of modest amounts of water on magmatic differentiation at Newberry Volcano, Oregon
Newberry Volcano—Central Oregon's Sleeping Giant
A field guide to Newberry Volcano, Oregon
The post-Mazama northwest rift zone eruption at Newberry Volcano, Oregon
Ice and water on Newberry Volcano, central Oregon
Chemical Analyses of Pre-Holocene Rocks from Medicine Lake Volcano and Vicinity, Northern California
Eruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Data
Database for the Geologic Map and Structure Sections of the Clear Lake Volcanics, Northern California
This geologic map database is a reproduction of U.S. Geological Survey Miscellaneous Investigations Map I–2362: “Geologic Map and Structure Sections of the Clear Lake Volcanics, Northern California” (Hearn, Donnelly-Nolan, and Goff, 1995). The database consists of a geologic map, three structural cross sections and a table of petrographic data for each map unit by mineral type, abundance, and sizeHazard boundaries for the volcanic hazard assessment of Medicine Lake volcano, California
Medicine Lake volcano (MLV) is a very large shield-shaped volcano located in northern California where it forms part of the southern Cascade Range of volcanoes. It has erupted hundreds of times during its half-million-year history, including nine times during the past 5,200 years, most recently 950 years ago. This record represents one of the highest eruptive frequencies among Cascade volcanoes an - Maps
Newberry Volcano's youngest lava flows
Most of Newberry Volcano's youngest lava flows are found within the Newberry National Volcanic Monument in central Oregon. Established November 5, 1990, the monument is managed by the U.S. Forest Service as part of the Deschutes National Forest. Since 2011, a series of aerial surveys over the monument collected elevation data using lidar (light detection and ranging) technology, which uses lasersGeologic map of Medicine Lake volcano, northern California
Medicine Lake volcano forms a broad, seemingly nondescript highland, as viewed from any angle on the ground. Seen from an airplane, however, treeless lava flows are scattered across the surface of this potentially active volcanic edifice. Lavas of Medicine Lake volcano, which range in composition from basalt through rhyolite, cover more than 2,000 km2 east of the main axis of the Cascade Range in - Publications
Filter Total Items: 23
Geologic field-trip guide to Medicine Lake Volcano, northern California, including Lava Beds National Monument
Medicine Lake volcano is among the very best places in the United States to see and walk on a variety of well-exposed young lava flows that range in composition from basalt to rhyolite. This field-trip guide to the volcano and to Lava Beds National Monument, which occupies part of the north flank, directs visitors to a wide range of lava flow compositions and volcanic phenomena, many of them wellAuthorsJulie M. Donnelly-Nolan, Timothy L. GroveOverview for geologic field-trip guides to Mount Mazama, Crater Lake Caldera, and Newberry Volcano, Oregon
These field-trip guides were written for the occasion of the International Association of Volcanology and Chemistry of the Earth’s Interior (IAVCEI) quadrennial scientific assembly in Portland, Oregon, in August 2017. The guide to Mount Mazama and Crater Lake caldera is an updated and expanded version of the guide (Bacon, 1989) for part of an earlier IAVCEI trip to the southern Cascade Range. TheAuthorsCharles R. Bacon, Julie M. Donnelly-Nolan, Robert A. Jensen, Heather M. WrightOverview for geologic field-trip guides to volcanoes of the Cascades Arc in northern California
The California Cascades field trip is a loop beginning and ending in Portland, Oregon. The route of day 1 goes eastward across the Cascades just south of Mount Hood, travels south along the east side of the Cascades for an overview of the central Oregon volcanoes (including Three Sisters and Newberry Volcano), and ends at Klamath Falls, Oregon. Day 2 and much of day 3 focus on Medicine Lake VolcanAuthorsL. J. Patrick Muffler, Julie M. Donnelly-Nolan, Timothy L. Grove, Michael A. Clynne, Robert L. Christiansen, Andrew T. Calvert, Juliet Ryan-DavisField-trip guide to the geologic highlights of Newberry Volcano, Oregon
Newberry Volcano and its surrounding lavas cover about 3,000 square kilometers (km2) in central Oregon. This massive, shield-shaped, composite volcano is located in the rear of the Cascades Volcanic Arc, ~60 km east of the Cascade Range crest. The volcano overlaps the northwestern corner of the Basin and Range tectonic province, known locally as the High Lava Plains, and is strongly influenced byAuthorsRobert A. Jensen, Julie M. Donnelly-NolanLate Holocene volcanism at Medicine Lake Volcano, northern California Cascades
Late Holocene volcanism at Medicine Lake volcano in the southern Cascades arc exhibited widespread and compositionally diverse magmatism ranging from basalt to rhyolite. Nine well-characterized eruptions have taken place at this very large rear-arc volcano since 5,200 years ago, an eruptive frequency greater than nearly all other Cascade volcanoes. The lavas are widely distributed, scattered overAuthorsJulie M. Donnelly-Nolan, Duane E. Champion, Timothy L. GroveStraddling the tholeiitic/calc-alkaline transition: The effects of modest amounts of water on magmatic differentiation at Newberry Volcano, Oregon
Melting experiments have been performed at 1 bar (anhydrous) and 1- and 2-kbar H2O-saturated conditions to study the effect of water on the differentiation of a basaltic andesite. The starting material was a mafic pumice from the compositionally zoned tuff deposited during the ~75 ka caldera-forming eruption of Newberry Volcano, a rear-arc volcanic center in the central Oregon Cascades. Pumices inAuthorsBen E. Mandler, Julie M. Donnelly-Nolan, Timothy L. GroveNewberry Volcano—Central Oregon's Sleeping Giant
Hidden in plain sight, Oregon's massive Newberry Volcano is the largest volcano in the Cascades volcanic arc and covers an area the size of Rhode Island. Unlike familiar cone-shaped Cascades volcanoes, Newberry was built into the shape of a broad shield by repeated eruptions over 400,000 years. About 75,000 years ago a major explosion and collapse event created a large volcanic depression (calderaAuthorsJulie M. Donnelly-Nolan, Wendy K. Stovall, David W. Ramsey, John W. Ewert, Robert A. JensenA field guide to Newberry Volcano, Oregon
Newberry Volcano is located in central Oregon at the intersection of the Cascade Range and the High Lava Plains. Its lavas range in age from ca. 0.5 Ma to late Holocene. Erupted products range in composition from basalt through rhyolite and cover ~3000 km2. The most recent caldera-forming eruption occurred ~80,000 years ago. This trip will highlight a revised understanding of the volcano's historyAuthorsRobert A. Jenson, Julie M. Donnelly-Nolan, Daniele McKayThe post-Mazama northwest rift zone eruption at Newberry Volcano, Oregon
The northwest rift zone (NWRZ) eruption took place at Newberry Volcano ~7000 years ago after the volcano was mantled by tephra from the catastrophic eruption that destroyed Mount Mazama and produced the Crater Lake caldera. The NWRZ eruption produced multiple lava flows from a variety of vents including cinder cones, spatter vents, and fissures, possibly in more than one episode. Eruptive behaviorAuthorsDaniele McKay, Julie M. Donnelly-Nolan, Robert A. Jensen, Duane E. ChampionIce and water on Newberry Volcano, central Oregon
Newberry Volcano in central Oregon is dry over much of its vast area, except for the lakes in the caldera and the single creek that drains them. Despite the lack of obvious glacial striations and well-formed glacial moraines, evidence indicates that Newberry was glaciated. Meter-sized foreign blocks, commonly with smoothed shapes, are found on cinder cones as far as 7 km from the caldera rim. ThesAuthorsJulie M. Donnelly-Nolan, Robert A. JensenChemical Analyses of Pre-Holocene Rocks from Medicine Lake Volcano and Vicinity, Northern California
Chemical analyses are presented in an accompanying table (Table 1) for more than 600 pre-Holocene rocks collected at and near Medicine Lake Volcano, northern California. The data include major-element X-ray fluorescence (XRF) analyses for all of the rocks plus XRF trace element data for most samples, and instrumental neutron activation analysis (INAA) trace element data for many samples. In additiAuthorsJulie M. Donnelly-NolanEruptive history and tectonic setting of Medicine Lake Volcano, a large rear-arc volcano in the southern Cascades
Medicine Lake Volcano (MLV), located in the southern Cascades ∼ 55 km east-northeast of contemporaneous Mount Shasta, has been found by exploratory geothermal drilling to have a surprisingly silicic core mantled by mafic lavas. This unexpected result is very different from the long-held view derived from previous mapping of exposed geology that MLV is a dominantly basaltic shield volcano. DetailedAuthorsJulie M. Donnelly-Nolan, Timothy L. Grove, M. A. Lanphere, Duane E. Champion, David W. RamseyNon-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government