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2014 Spring Break field trip: Kettleman Hills and Death Valley area, page 1

by Dave Smith, with contributions from Junying Lim, Camilla Souto, Lisa White, and Seth Finnegan

In January of this year, Assistant Professor of Integrative Biology and UCMP Curator Seth Finnegan sent an e-mail out to the museum community to gauge the interest in a Spring Break field trip. His idea was to spend a day looking at Cenozoic sections in the Central Valley, such as the Pliocene outcrops in the Kettleman Hills near Coalinga, and then to move on to the Death Valley area, where we'd spend a few days examining some classic Paleozoic marine sequences. Seth said "My intent is to provide graduate students who may not have spent much time in the field an opportunity to see fossils in their stratigraphic context, to learn some of the basics of using sedimentology and taphonomy to make paleoecological inferences, and to consider the ways in which paleontological information is filtered through the geological record."

Enough people were interested to make such a trip worthwhile, so the logistics were worked out, two four-wheel-drive vehicles were reserved, permission to visit the Kettleman Hills localities was obtained, and lodgings were arranged for in Shoshone, just south of Death Valley (for two nights; we would be camping the rest of the time).

On Sunday, March 23, all interested parties gathered at the North Berkeley BART parking lot. Some people planned to go only as far as the Kettleman Hills and would be returning to Berkeley late Monday. This group included UCMP Director Charles Marshall, his wife Swee Peck Quek and their daughter Kiri, Assistant Director for Education and Public Programs Lisa White, Senior Museum Scientist Pat Holroyd, and grad student Liz Ferrer. Those joining Seth for the whole week would be UCMP graphic designer Dave Smith and grad students Junying Lim, Winnie Hsiung, Camilla Souto, Lucy Chang, Ashley Poust, and Renske Kirchholtes; these eight went in the two rented GMC Yukons, while Charles and Lisa drove their own cars.

After a two-hour-and-45-minute drive, we reached Coalinga, then, heading west, we followed Lisa to exposures of the late Miocene Santa Margarita Formation along Los Gatos Creek Road. These are primarily light-colored sandstones with some conglomerates and occasional large boulders, all deposited when the area was a shallow shelf setting. Continuing west, Lisa pointed out some nicely bedded turbidites — deep ocean, high-density sediment flow deposits from the Cretaceous Moreno Formation of the Great Valley Sequence — before pulling into the somewhat remote Los Gatos Creek County Park. Serenaded by howling coyotes and hooting owls, we spent a pleasant night of camping here.

Rendezvous at North Berkeley BART
Santa Margarita Formation
Stopping at an outcrop of the Santa Margarita Formation
Preparing to leave Los Gatos Creek County Park
Stars over Los Gatos Creek County Park
Click on any photo on this page to see an enlargement. Top left: The group gathers at the North Berkeley BART parking lot. Photo by Dave Smith. Top middle: Our first stop is at an exposure of the Santa Margarita Formation. Photo by Dave Smith. Bottom left: Sandstones of the late Miocene Santa Margarita Formation. Photo by Camilla Souto. Bottom middle: Preparing to leave the campground at Los Gatos Creek County Park. Photo by Dave Smith. Right: A time-exposure photo of the Milky Way from Los Gatos Creek County Park. Photo by Junying Lim.

On Monday, with Lisa leading the way, we headed south of Coalinga and entered the Kettleman Hills, driving along poorly maintained oil company roads to a series of San Francisco State University localities that Lisa had frequented during her tenure there. The Kettleman Hils are a series of elongated domes or plunging anticlines and the first stop was at a thick exposure of the early Pliocene Patinopecten Zone (named for a species of scallop found in these rocks) within the Etchegoin Formation. The zone's brown sandstones are full of the sand dollar Dendraster and bivalves preserved in life position. Above the Patinopecten Zone is the younger, browner, lichen-covered Macoma Zone (Macoma is a large marine clam). These rocks and their fossils tell us that this was a shallow marine to estuarine setting during the early Pliocene.

At our first Kettleman Hills stop, Lisa provides some background
A layer of bivalves in the Patinopecten Zone
Negotiating pipes on the way to the first locality
A layer of sand dollars in the Patinopecten Zone
Half-buried and rusted pipelines crisscross these hills
The group examining an exposure at a locality in the Siphonalia Zone
Top left: Before heading to our first Kettleman Hills locality, Lisa provides some background. Photo by Dave Smith. Top middle: Negotiating pipelines on the way to the locality. Photo by Dave Smith. Top right: Half-buried and rusted pipelines crisscross these hills. Photo by Dave Smith. Bottom left: A layer of bivalves within the Patinopectin Zone of the Etchegoin Formation. Photo by Camilla Souto. Bottom middle: Just below the bivalve layer is this one containing a concentration of Dendraster sand dollars. Photo by Camilla Souto. Right: Examining an exposure in the Siphonalia Zone. Photo by Dave Smith.

We continued on to a good exposure of the middle Pliocene Siphonalia Zone (Siphonalia is a marine gastropod), stratigraphically just above the Macoma Zone. The rocks here are composed of brown silts and bluish sandstones. Then, leaving the oilfield, it was out to Skyline Boulevard and northeast towards route 5. We parked on the shoulder, climbed through a barbed wire fence, and hiked to the easternmost ridge of the Kettlemans, on the eastern limb of the North Dome Anticline. In the rocks we traversed here — from the upper Pliocene Acila Zone (Acila is a small marine clam) of the San Joaquin Formation to the Pleistocene Amnicola Zone (Amnicola is a freshwater gastropod) of the Tulare Formation — the demise of the marine basin was chronicled, with oyster beds indicating the transition from a saltwater to freshwater environment. In an upper section, a gypsum evaporite layer signaled the advent of terrestrial deposition.

Renske, Ash, and Jun check out the Siphonalia Zone exposure
Closeup of a bivalve layer with rock hammer for scale
Two bivalve-rich layers in the Siphonalia Zone
A razor clam in the Siphonalia Zone
Top left: Renske, Ash, and Jun check out the Siphonalia Zone exposure. Photo by Winnie Hsiung. Bottom left: A close-up of one of the bivalve layers in the Siphonalia Zone with a rock hammer for scale. Photo by Camilla Souto. Middle: Two distinct bivalve layers in the Siphonalia Zone. Photo by Dave Smith. Right: A close-up of a razor clam. That's the tip of a rock hammer on the right. Photo Winnie Hsiung.

Our final destination in the Kettleman Hills: the top of that distant ridge
Examining a ledge at the top of the ridge
Charles, Pat, and Jun pause on the way up the hill
Molds and casts of bivalves on the underside of the ledge
Lucy and Renske on the ridge
This gypsum evaporite layer is an indicator of the advent of terrestrial deposition
Top left: Our final destination in the Kettleman Hills: the top of that distant ridge. Photo by Camilla Souto. Top middle: Charles, Pat, and Jun pause on the way up the hill. Photo by Camilla Souto. Top right: Lucy and Renske on the ridge. Photo by Winnie Hsiung. Bottom left: Examining a ledge at the top of the ridge. Photo by Junying Lim. Bottom middle: Molds and casts of bivalves on the underside of the ledge. Photo by Dave Smith. Right: This gypsum evaporite layer is an indicator of the advent of terrestrial deposition. Photo by Camilla Souto.

Westernmost ridge of the Kettleman Hills A group photo in the Kettleman Hills
Left: Looking south along the spine of the easternmost ridge of the Kettleman Hills, on the eastern limb of the North Dome Anticline. Route 5 and the Central Valley are east of this ridge (left side of the photo). Photo by Winnie Hsiung. Right: A group photo in the Kettleman Hills. From left are Dave, Pat, Charles, Camilla (in front), Jun, Seth, Winnie, Ash, Liz, Renske, and Lucy … and Lisa White took the photo.

At this point, Charles and his family — and Lisa with Pat and Liz — headed back to Berkeley, while the rest of us continued on to Bakersfield and Tehachapi, arriving at Red Rock Canyon State Park after sunset. We did not explore the park, but appreciated its badlands composed of Miocene mudstones and sandstones of terrestrial origin.

Preparing for another day at our campsite in Red Rock Canyon State Park
Joshua trees and Red Rock Canyon cliffs
The eroded cliffs on the south side of the campground
Stars over the campground
Another time-exposure photo of the stars above our campsite
Top left: Preparing for another day at our campsite in Red Rock Canyon State Park. Photo by Winnie Hsiung. Top middle: The eroded cliffs on the south side of the campground. Photo by Camilla Souto. Bottom left: Joshua trees and the Red Rock Canyon cliffs. Photo by Camilla Souto. Bottom middle: Stars over the campground. A campfire reflects off the cliffs. Photo by Junying Lim. Right: Another time-exposure photo of the stars above our campsite. Photo by Junying Lim.

Tuesday morning's first stop was Fossil Falls Scenic Area, north of Little Lake. The falls, now dry and cutting through lava beds, mark the course of the vanished Owens River. Then it was up 395 and east on 190 towards Death Valley National Park. We stopped at the Father Crowley Vista to take in the amazing view of the Panamint Valley to the east. Across the valley was the Panamint Range, with its light-colored Paleozoic carbonates beneath darker Cenozoic lava flows. We were now in the Basin and Range Province where crustal stretching has resulted in valleys — like Panamint and Death Valleys — formed from downthrown blocks of land. Continuing on into the park, we set up camp at the Stovepipe Wells campground. Although it was still early in the day, we all pitched our tents in order to "claim our turf."

Examining the now dry falls Water-polished lava in the former river bed The volcanic landscape at Fossil Falls
A panoramic view of the Panamint Valley
Seth explains the geology of the Panamint Valley The colorful rocks of Rainbow Canyon Zooming in on the rocks of the Panamint Range
Top left: Examining the now dry falls at Fossil Falls Scenic Area. Photo by Junying Lim. Top middle: Water-polished lava in the now dry river bed. Photo by Winnie Hsiung. Top right: The volcanic landscape at Fossil Falls. Photo by Dave Smith. Middle panorama: A panoramic view of the Panamint Valley as seen from the Father Crowley Vista. Photo by Junying Lim. Bottom left: Seth explains the geology of the Panamint Valley. Photo by Dave Smith. Bottom middle: The colorful rocks of Rainbow Canyon as seen from the Father Crowley Vista. Photo by Camilla Souto. Bottom right: The layered rocks of the Panamint Range on the east side of the valley. Photo by Camilla Souto.

Back in the two Yukons, we drove out Daylight Pass Road to where the one-way Titus Canyon Road begins. After a quick stop at the short-lived ghost town of Leadfield (it survived for less than a year), we drove deeper into the canyon and stopped to look at exposures of the Bonanza King Formation. These thick Middle to Late Cambrian rocks are composed primarily of dolomite and dolomitic limestones, some with alternating light and dark layers of equal thickness. Seth pointed out that such layers have been shown in some cases to correlate with Milankovich climate cycles driven by cyclic changes in the Earth's orbital parameters. Within the Bonanza King we found trilobite hash and ripple marks, evidence of its marine origins.

Titus Canyon Road descending into Titus Canyon proper as seen from Red Pass
The short-lived mining town of Leadfield
Top: Titus Canyon Road descending into Titus Canyon proper as seen from Red Pass. Photo by Dave Smith. Bottom: The short-lived mining town of Leadfield. Photo by Winnie Hsiung.

Driving through Titus Canyon, we would stop periodically to check out the changing geology
The alternating layers of equal thickness that may correlate with Milankovitch climate cycles
A view down the canyon
Seth examines some ripple marks
Lucy Chang poses by an impressive breccia
This Desert Bighorn Sheep had a badly broken leg
The whole group climbs up for a look at the ripple marks
The Titus Canyon narrows
The morning following our windy night at Stovepipe Wells campground
Top row left: Driving through Titus Canyon, we would stop periodically to check out the changing geology. Photo by Dave Smith. Top row middle: Seth examines some ripple marks. Photo by Dave Smith. Top row right: The whole group climbs up for a look at the ripple marks. Photo by Dave Smith. Second row left: The alternating layers of equal thickness that may correlate with Milankovitch climate cycles. Photo by Camilla Souto. Second row middle: Lucy Chang poses by an impressive breccia. Photo by Dave Smith. Second row right: The Titus Canyon narrows. Photo by Camilla Souto. Bottom row left: A view down the canyon. Photo by Camilla Souto. Bottom row middle: This Desert Bighorn Sheep had a badly broken leg. Back at camp, we learned that a crew had been sent out to rescue the animal. Photo by Camilla Souto. Bottom row right: The morning following our windy night at Stovepipe Wells campground. Photo by Dave Smith.