D

0 500 1,000 1,500 FEET

0 100 300 500 METERS

PAULINA LAKE ROAD

D2

D1

D4

D5

D3

D. Map showing Newberry Volcano’s youngest lava flow, the 1,300-yr-old Big Obsidian Flow (orange). This eruption 

began with explosions that sent volcanic ash east as far as Idaho. The lava dome (D1) above the main vent stands 

above the craggy surface of the obsidian flow. The lava flow’s inhospitable surface is pockmarked by round gas-related 

cavities (D2), and wrinkled by lava flow pressure ridges (D3) showing flow direction to the north. A popular unpaved 

hiking trail (black dash-dot line) ascends by stairs to the upper surface of this spectacular rhyolite flow. Overlooking 

the Big Obsidian Flow is the nearly 8,000-ft-high Paulina Peak (D4), the highest point on the caldera rim. The peak is 

made of rhyolite that erupted about 80,000 years ago. The caldera collapse and subsequent glaciation beheaded the 

lava flow, and sections of these oversteepened cliffs collapsed to form the landslide (D5) that appears as the rumpled 

surface below the peak. An unpaved seasonal road ascends to the top of the peak that, on a clear day, offers one of 

the premier views in all of Oregon—the crest of the Cascade Range from Mount Shasta, CA to Mount Adams, WA.

C. Map showing the central rhyolite fissure (red) that erupted across the caldera about 7,500 years ago and includes 

craggy-surfaced lava flows and the nearly 700-ft-high Central Pumice Cone (C1). This prominent feature was built by the 

explosive interaction of rhyolitic magma and water. As the cone grew, water was forced away from the vent, allowing 

lava to ooze into the central crater. North of the cone, the Inter Lake Flow (C2) flowed south and then descended both 

sides of the central ridge into the basins occupied by the caldera lakes. The East Lake Fissure (C3), shown in purple, 

marks the extension of the northwest rift zone eruption into the caldera. 

PAULINA LAKE

EAST LAKE

C1

C2

C3

C

0 500 1,000 1,500 FEET

0 100 200 300 400 500 METERS

B. Map showing Newberry Volcano’s northwest rift zone eruption that was caused when the 

ground surface was stretched and broken, allowing magma to rise and erupt. The eruption 

7,000 years ago opened multiple fissures, producing volcanic vents for 20 miles, mainly to the 

northwest of the caldera. Halfway up the volcano’s flank, multiple vents (B1) opened close to 

where the Lava Cast Forest Trailhead is today. The lava from these vents engulfed a stand of 

trees, chilled and solidified against them, and then burned away the wood leaving behind tree 

molds. Many of these molds can be seen along a paved trail (black dash-dot line) at Lava Cast 

Forest. Further north, another vent erupted lava along a crack or fissure (B2).

Photograph showing fissure eruption at Mauna Loa, Hawaii during its 1984 

eruption (photo by J. Griggs, U.S. Geological Survey). Fissure eruptions at 

Newberry Volcano may have occurred in a similar way. Note person in the 

lower left-hand corner of the photograph.

Photograph showing tree molds scattered along the Lava Cast Forest trail. 

The molds were left behind when trees were engulfed by less viscous lava 

that erupted from a nearby vent.

B

0 500 1,000

0 500 METERS

B1

B2

100 200 300 400

1,500 FEET

Lava Cast

Forest Trailhead

~1.5 FEET

LAVA CAST FOREST ROAD

A. Map showing Lava Butte, the northernmost and largest among the vents of Newberry 

Volcano’s northwest rift zone eruption. The lidar image shows the 500-ft-high cinder cone 

(A1), its 200-ft-deep central crater, and multiple flow lobes (A2) emerging from a boca 

(Spanish for mouth) (A3), at the base of the cone. Red arrows mark flow paths of lava that 

was erupted from the boca. Also nearby are several fissure vents (A4), small lava flows (A5), 

and a set of parallel extensional cracks that project to the southeast along the northwest rift 

zone (A6). A paved trail (black dash-dot line) from the Lava Lands Visitor Center, located 

adjacent to Highway 97, extends north into the boca. A paved road (open seasonally) to the 

top of the cinder cone provides an expansive view to the southeast, encompassing the 

cinder-cone-dotted northwest flank of Newberry Volcano, and a view of the Cascade Range 

to the west, including the Three Sisters and Mount Bachelor.

Image showing oblique view (as if flying north) of Lava Butte using lidar data. Explosive eruptions built the cinder cone to its full height before lava broke through the 

side of the cone at a boca (A3), producing multiple layered terrace-like lobes of lava. 

Lava Lands

Visitor Center

(Open Seasonally)

A1

A2

A3

A4

A5

A6

A

0 500 1,000 1,500 FEET

A3

0 300 500 METERS

to

Bend

Lava Butte 97

100

NORTHWEST RIFT ZONE

PAULINA CREEK

FALLS

EAST LAKE

Paulina

Peak

Inter Lake

Flow

Inter Lake

Flow

NORTHWEST RIFT ZONE

PAULINA CREEK

FALLS

EAST LAKE

Big Obsidian

Flow Paulina

Peak

A

Lava Cast

Forest

Lava Cast

Forest

B

C

D

0 1 2 4 MILES

0 2 4 KILOMETERS

97

42

PAULINA LAKE ROAD

Lava Lands

Visitor Center

Lava Lands

Visitor Center

Central

Pumice Cone

Central

Pumice Cone

PAULINA

LAKE

ADDITIONAL READING

Donnelly-Nolan, J.M., Stovall, W.K., Ramsey, D.W., Ewert, J.W., and Jensen, R.A., 2011, Newberry Volcano—central Oregon’s 

sleeping giant: U.S. Geological Survey Fact Sheet 2011–3145, 6 p., available at http://pubs.usgs.gov/fs/2011/3145/.

NEWBERRY NATIONAL

VOLCANIC MONUMENT

Image from U.S. Geological Survey, National Elevation Dataset

Universal Transverse Mercator projection

Lava 

Butte

Lava 

Butte

Lava 

Butte

Lava 

Butte

Three Sisters

Bend

Crater Lake

(Mount Mazama)

Mount Hood

•

OREGON

Boundary of Newberry

Volcano lavas

Newberry National

Volcanic Monument

LOCATION MAP

▲

▲▲▲

O R E G ON D EPA R T M E N T O F G E O LO G Y A N D M I N E RA L I N D U ST R IES

1937 U.S. Department of the Interior

U.S. Geological Survey

Newberry Volcano’s Youngest Lava Flows

By

Joel E. Robinson, Julie Donnelly-Nolan, and Robert A. Jensen

2015

Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply 

endorsement by the U.S. Government

For sale by U.S. Geological Survey, Information Services, Box 25286, Federal Center, Denver, CO 80225, 1–888–ASK–USGS

Digital files available at http://dx.doi.org/10.3133/sim3329 or http://pubs.usgs.gov/sim/3329/

Suggested Citation: Robinson, J.E., Donnelly-Nolan, J.M., and Jensen, R.A., 2015, Newberry Volcano’s Youngest Lava 

Flows: U.S. Geological Survey Scientific Investigations Map 3329, 1 sheet, http://dx.doi.org/10.3133/sim3329. 

ISSN 2329-132X (online)

ISSN 2329-1311 (print)

http://dx.doi.org/10.3133/sim3329

Scientific Investigations Map 3329

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 lasers to directly measure the ground surface. These data record previously unseen 

detail in the volcano’s numerous lava flows and vents. On average, a laser return was collected from the ground’s surface every 2.17 feet (ft) with ±1.3 inches vertical 

precision.

The central caldera is visible in the lower right corner of the center map, outlined by the black dashed line. The caldera collapsed about 75,000 years ago when 

massive explosions sent volcanic ash as far as the San Francisco Bay area and created a 3,000-ft-deep hole in the center of the volcano. The caldera is now partly 

refilled by Paulina and East Lakes, and the byproducts from younger eruptions, including Newberry Volcano’s youngest rhyolitic lavas, shown in red and orange. The 

majority of Newberry Volcano’s many lava flows and cinder cones are blanketed by as much as 5 feet of volcanic ash from the catastrophic eruption of Mount 

Mazama that created Crater Lake caldera approximately 7,700 years ago. This ash supports abundant tree growth and obscures the youthful appearance of Newberry 

Volcano. Only the youngest volcanic vents and lava flows are well exposed and unmantled by volcanic ash. More than one hundred of these young volcanic vents 

and lava flows erupted 7,000 years ago during Newberry Volcano’s northwest rift zone eruption.

Printed on recycled paper