Death Valley National Park geology, Part III: Mesozoic through Paleogene

We made it out of the Precambrian. We made it out of the Paleozoic. We aren't nearly out of Death Valley, though. There's still about 250 million years to go, during which the valley was converted from marine property to land, became gently toasted by massive subterranean plutons, and was eventually pulled apart into the modern topography over about 15-20 million years of nonstop faulting, with volcanic eruptions and inland lakes thrown in for variety.

The world's longest caption, shorter for once. Unconformities are not depicted except as a consequence of a missing time unit. Certain subtleties are omitted. Unit descriptions are shortened (Fm=Formation, Mt=Mountain, Mts=Mountains). Contemporaneous units are depicted with the more northerly formation on the left side of the table. The depicted lateral divisions are not proportional to DEVA land area. Ma refers to millions of years. Dates should be understood as "circa".

The Mesozoic (252 to 66 million years ago) is sparse on the ground at Death Valley National Park (DEVA). In fact, unless you are a student of igneous rocks, it's easy to overlook that it's represented at all. You get a grand total of one and a half sedimentary units: the marine Butte Valley Formation, of Early Triassic age, and the sedimentary component of the volcanic Warm Springs Formation, of uncertain Jurassic age. The presence of a marine formation, and a second formation that has been interpreted as in part a volcanically disrupted sea bed, sounds to me like there were probably more sedimentary Triassic and Jurassic rocks at one time, but they were lost to erosion. There are a few mollusks in the Butte Valley Formation, but that's about it in terms of fossils.

The real show in the Mesozoic here involves molten rock, which is a pretty good way to start any show. The conversion of the western margin of North America to an active margin set up a tectonic conveyor belt that dragged island arcs and continental fragments toward North America and their ultimate destinies as expensive coastal California land. A side effect of subducting crust is the creation of magma beneath the plate doing the over-riding, leading to igneous intrusions and the formation of volcanoes (sort of a "parting shot" for the destroyed plate). Mesozoic western North America was no exception. We got a nice Andean-style arc out of the arrangement, although of course it's not there any more. All that are left are traces; in fact, the Warm Spring Formation formed on the east side of a middle Mesozoic incarnation of the arc. In addition to the volcanoes, the area also was the recipient of some metamorphism. The most significant event in the vicinity, or at least the most significant that we know about, was the emplacement of the Sierra Nevada batholith (if you don't recognize the name, think Yosemite's rocks). The Sierra Nevada is made up of blurps of magma that cooled at depth during the Cretaceous and only became exposed over the past few million years. These intrusions also ended up baking rocks around them, including some in the Funeral Range of DEVA. Examples of DEVA igneous bodies of Mesozoic age include the Hunter Mountain batholith (Early–Middle Jurassic) and the Hall Canyon pluton (Late Cretaceous).

We get one of the few significant gaps in the rock record at DEVA next. If not for some dikes reportedly dating to 56 to 54.7 million years ago, there'd be nothing at the park between the end of the Cretaceous and about 34 million years ago. This absence of geology makes it difficult to say anything useful about this stretch of time in the park, so let's skip straight ahead to the first sedimentary formation of the Cenozoic, the Titus Canyon Formation. DEVA has a lot of local Cenozoic formations, and many follow a general pattern: early stage conglomeratic basin fill followed by finer-grained fluvial and lacustrine fill in the center of the basin fringed by alluvial fan conglomerates, punctuated by volcanic ash or tuff beds and sometimes volcanic flows. The Titus Canyon Formation is notable as the one Death Valley formation with a significant record of mammal body fossils. These include brontotheres, Nature's way of saying "hello, you've reached the Eocene." Most of the fossils were described back in the 1930s and 1940s, so it would probably be helpful to have another look at them. In addition to the mammals, plants and fishes have also been described from the Titus Canyon Formation. It wound down between about 27 and 24 million years ago, to be followed by the Ubehebe Formation, one of the dozen or so named formations that fill out the Death Valley stratigraphic column between the Oligocene and the present. It is an ironclad rule of Death Valley geology that there is always another Cenozoic formation to be named and described, for which we can thank Death Valley's pervasive faulting and basin creation. That all shows up in the next, and final, entry.

Selected references and chart references:

Beyene, M. A. 2011. Mesozoic burial, Mesozoic and Cenozoic exhumation of the Funeral Mountains core complex, Death Valley, southeastern California. Dissertation. University of Nevada at Las Vegas, Las Vegas, Nevada.

Cornwall, H. R., and F. J. Kleinhampl. 1964. Geology of Bullfrog quadrangle and ore deposits related to Bullfrog Hills Caldera, Nye County, Nevada, and Inyo County, California. U.S. Geological Survey, Washington, D.C. Professional Paper 454-J.

Hall, C. A. 2007. Introduction to the geology of southern California and its native plants. University of California, Berkeley, California.

Hoisch, T. D., M. L. Wells, M. A. Beyene, S. Styger, and J. D. Vervoort. 2014. Jurassic Barrovian metamorphism in a western U. S. cordilleran metamorphic core complex, Funeral Mountains, California. Geology 42(5):399–402.

Hunt, C. B., and D. R. Mabey. 1966. Stratigraphy and structure, Death Valley, California. U.S. Geological Survey, Washington, D.C. Professional Paper 494-A.

Johnson, B. K. 1957. Geology of a part of the Manly Peak Quadrangle, southern Panamint Range, California. University of California Publications in Geological Sciences 30(5):353–423.

Labotka, T. C., and A. L. Albee. 1988. Metamorphism and tectonics of the Death Valley region, California and Nevada. Pages 715–736 in W. G. Ernst, editor. Metamorphism and crustal evolution of the western United States. Prentice-Hall, Englewood Cliffs, New Jersey. Rubey Volume 7.

Marzolf, J. E., and T. H. Anderson. 2005. Lower Mesozoic facies and crosscutting sequence boundaries: constraints on displacement of the Caborca terrane. Pages 283–308 in T. H. Anderson, J. A. Nourse, J. W. McKee, and M. B. Steiner, editors. The Mojave-Sonora megashear hypothesis: development, assessment, and alternatives. Geological Society of America, Boulder, Colorado. Special Paper 393.

Miller, C. B., and L. A. Wright. 2002. Geology of Death Valley National Park. Kendall Hunt Publishing, Dubuque, Iowa.

Miller, R. R. 1945. Four new species of fossil cyprinodont fishes from eastern California. Journal of the Washington Academy of Sciences 35(10):315–321.

Niemi, N. A. 2002. Extensional tectonics in the Basin and Range Province and the geology of the Grapevine Mountains, Death Valley region, California and Nevada. Dissertation. California Institute of Technology, Pasadena, California.

Ragan, D. M. 1953. Geology of Butte Valley, Inyo County, California. Thesis. University of Southern California, Los Angeles, California.

Snow, J. K., and D. R. Lux. 1999. Tectono-sequence stratigraphy of Tertiary rocks in the Cottonwood Mountains and northern Death Valley area, California and Nevada. Pages 17–64 in L. A. Wright and B. W. Troxel, editors. Cenozoic basins of the Death Valley region. Geological Society of America. Boulder, Colorado. Special Paper 333.

Snow, J. K., and C. White. 1990. Listric normal faulting and synorogenic sedimentation, northern Cottonwood Mountains, Death Valley region, California. Pages 413–445 in B. P. Wernicke, editor. Basin and Range extensional tectonics near latitude of Las Vegas, Nevada. Geological Society of America, Boulder, Colorado. Memoir 176.

Stock, C. 1936. Titanotheres from the Titus Canyon Formation, California. Proceedings of the National Academy of Sciences 22(11):656–661.

Stock, C. 1949. Mammalian fauna from the Titus Canyon Formation, California. Carnegie Institute of Washington Publication 584:231–244.

Stock, C. and F. Bode. 1935. Occurrence of lower Oligocene mammal bearing beds near Death Valley, California. Proceedings of the National Academy of Sciences 21(10):571–579.

Stone, P., C. H. Stevens, and M. J. Orchard. 1991. Stratigraphy of the Lower and Middle(?) Triassic Union Wash Formation, east-central California. U.S. Geological Survey, Reston, Virginia. Bulletin 1928.

Stone, P., B. J. Swanson, C. H. Stevens, G. C. Dunne, and S. S. Priest. 2009. Geologic map of the southern Inyo Mountains and vicinity, Inyo County, California. U.S. Geological Survey, Reston, Virginia. Scientific Investigations Map 3094. Scale 1:24,000.

Wrucke, C. T., P. Stone, and C. H. Stevens. 2007. Geologic map of the Warm Spring Canyon area, Death Valley National Park, Inyo County, California. Scientific Investigations Map 2974. Scale 1:24,000.