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Paul Buchheim, PhD
Program Coordinator, Earth and Biological Sciences
School of Medicine
Professor, Earth and Biological Sciences
School of Medicine
Member, Faculty of Graduate Studies
Presentations    Research Presentations -- International
  • H. Paul Buchheim, S.M. Awramik, and C. Shultz, 2007Lacustrine Stromatolites: The neglected “black box” of climate, chemistry, hydrodynamics, and tectonics data in ancient Lake basins,  4th International Limnogeology Congress, July 11-14, 2007, Barcelona, Spain ( 7/2007 )
  • Nyborg, T. and H.P. Buchheim. "Cenozoic fossil vertebrate tracks of the Copper Canyon Unit, Death Valley National Park, California, USA." Second International Paleontological Conference. Beijing, China ( 6/2006 )
  Research Presentations -- National
  • PALEOENVIRONMENTAL FACTORS CONTROLLING MICROBIALITE BIOHERM DEPOSITION AND DISTRIBUTION IN THE GREEN RIVER FORMATION 2009 Portland GSA Annual Meeting (18-21 October 2009) BUCHHEIM, H. Paul1, AWRAMIK, Stanley M.2, and LEGGITT, V. Leroy1, (1) Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350, pbuchheim@llu.edu, (2) Department of Earth Science, University of California, Santa Barbara, Preston Cloud Research Laboratory, Santa Barbara, CA 93106 ( 10/2009 )
    The Eocene Green River Formation of Wyoming, Utah, and Colorado contains the most diverse and abundant occurrences of lacustrine microbialites known. One of the largest oil fields in the Uinta Basin, Utah, is sourced from a 30 m thick, 4 km long microbialite/oolite bioherm that has produced close to a million barrels of oil. Outcrop exposures of analogous bioherms occur in the Piceance Creek Basin (Colorado), Fossil Basin (Wyoming), and Green River Basin (Wyoming). These occurrences provide analogs for exploration of petroleum in other lake basins. Recently described microbialite bioherms up to 9 m thick from the La Barge area of the Green River Basin of Wyoming may provide the best outcrop analogs. The bioherms are composed of domical and columnar stromatolites, some 2 to 3 meters in diameter, as well as ooids, oncoids, calcified caddisfly larval cases, and other carbonate components. Laterally, bioherms are discontinuous (each up to 150 m in diameter); however, the lake-margin bioherm system is found in a large arc (over 250 km) across the western, northern, and eastern greater Green River Basin. Bioherms grade laterally into adjacent calcitic lake facies over a distance of 100 meters and into dolomitic oil shales of the Wilkins Peak Member over 15 km. Since thick microbialites are reservoir rocks in some oil fields, it is important to understand the paleoenvironmental conditions that favor the formation of bioherms over biostromes. In the southeastern part of the Green River Basin, biostromes are the exclusive megastructure of microbialites, whereas in the northwest to northeast part of the basin bioherms occur in addition to biostromes. The biostromes are found in facies sequences interpreted to be balanced-filled lake deposits where regressions and transgressions over very low gradients were frequent. Bioherms appear to have been favored by under-filled lake basin conditions, where localized fresh-water deposition was restricted to the lake margins. The Green River Formation bioherms provides valuable insights into the exploration of microbialites as petroleum reservoirs in ancient lake basins. Further study of the bioherms of the Green River Formation should provide data that will help to better understand their origin, stratigraphic, and spatial location in ancient lake basins.
  • TUFA MOUNDS, TRACKS AND THE TECTONIC/CLIMATIC EVOLUTION OF THE LACUSTRINE MIOCENE-PLIOCENE COPPER CANYON “FORMATION,” DEATH VALLEY, CALIFORNIA NYBORG, Torrey and BUCHHEIM, H. Paul, Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350, tnyborg06g@llu.ed; 2009 Portland GSA Annual Meeting (18-21 October 2009) ( 10/2009 ) Link...
    The Copper Canyon “Formation” (CCF) represents a diverse Cenozoic basin fill sequence controlled by tectonic (uplift rate, accommodation space, and spatial distribution) and climate (precipitation/evaporation P/E ratios and sediment supply) driven deposition within a hydrologically-closed lake. The CCF represents approximately 1800 meters of fanglomerate and fluvial-lacustrine sediments contained and well exposed within a five square mile rectangular fault bounded basin exposed within Copper and Coffin Canyons in the Black Mountains of Death Valley National Park, California. The CCF is significant because it preserves numerous shoreline-playa features including highly abundant and diverse mammal and bird tracks. Three basalt flows, along with a tuff bed stratigraphically above the CCF, constrain the age between ~5 and 3Ma. Initial CCF deposits represent active uplift recorded by numerous fanglomerates deposited as debris flows fining upward into mud-drapes. The fanglomerate provenance suggests a local source and rapid episodic deposition. Fanglomerates become less dominant up section and interfinger with trangressive-regressive playa-lake deposits. Cyclicity of lacustrine sequences is interpreted as humid-wet and arid-dry climate cycles consisting of: evaporite facies (reflecting a hypersaline lake); alternating beds of calcimicrite and dolomicrite (representing alternating fresh and saline conditions); and bioclastic carbonate and limestone beds containing tufa mounds (reflecting active spring deposition). Track distribution and abundance is tied into the appearance of the tufa mounds and associated bioclastic carbonates. Lower in the lacustrine section tracks and bioclastic carbonates rich in gastropods, ostracods and plant fragments are scarce; however higher in the section, where tufa mound deposits appear, tracks and bioclastic carbonates are very abundant. The evolution of the ancient Copper Canyon Lake represents a shift from an under-filled (evaporitic facies) to a balanced-filled (fluctuating profundal) lake. The CCF deposits end abruptly ~3Ma reflecting basin in-filling (loss of accommodation space), probably due to a decline in tectonic activity in Death Valley. 2009 Portland GSA Annual Meeting (18-21 October 2009)
  • Nyborg, Torrey and Paul Buchheim,  Lacustrine Tufa Mounds of the Miocene-Pliocene Copper Canyon “Formation,” Death Valley, California: Relationship to Organism Abundance and Distribution, 2009, AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009 ( 6/2009 )
  • Nyborg, Torrey and Buchheim, Paul H.  2007. Fossil mammal and bird tracks of the Copper Canyon Unit, Death Valley National Park, California, USA: the most abundant and diverse assemblage of fossil tracks in North America and possibly the world. Cenozoic Vertebrate tracks and traces. New Mexico Museum of History and Science, Bulletin 42, p. 139. ( 11/2007 )
  • STROMATOLITES AS INDICATORS OF LAKE CLIMATE AND CHEMISTRY BUCHHEIM, H. Paul1, AWRAMIK, Stanley2, and SHULTZ, Carol1, (1) Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350, pbuchheim@llu.edu, (2) Department of Geological Sciences, Univ of California, Santa Barbara, Santa Barbara, CA 93106 ( 10/2007 ) Link...
    Lacustrine stromatolites can provide substantial information about lake chemistry and climate. Studies of Eocene Green River Formation stromatolites in Wyoming provide a basis for a better understanding these factors. Detailed mineralogic and isotopic analysis of laminae in a Laney Member stromatolitic biostrome presents a record of climate change and chemical variability: d18O and d13C show an upward light trend indicating wetter climate. Calcite/dolomite ratio increases upward, consistent with the lighter isotopic trend. Tracing the biostrome normal to shoreline, lateral salinity gradients are indicated by a decreasing calcite/dolomite ratio and more positive d18O and d13C values toward the more saline lake center. Observations on the occurrence of stromatolites in two other members of the Green River Formation (Tipton and Wilkins Peak) illustrate, like in the Laney Member, that stromatolite occurrence is related to basic lake type and corresponding lake chemistry. In overfilled, calcium-rich, fresh-water lakes, stromatolites formed near basin margins with a vertical facies association of stromatolites alternating with near-shore, high-energy deposits (oolites, flat pebble conglomerate (fpc), and storm deposits). Balanced-filled, carbonate-rich lakes commonly produced a lithofacies association of, from base to top, dolostone, fpc with ooids/peloids, stromatolites, and kerogen-rich carbonates. Underfilled lakes developed the same lithofacies package, but lacked stromatolites because lake waters were severely under-saturated with respect to calcite. We conclude that lake-type can be used to make predictions concerning the occurrence and facies relationships of stromatolites. For example, an underfilled saline-alkaline lake is generally deficient in Ca++, and it would be predicted that stromatolites would not be common, except perhaps near fresh-water fluvial or spring inputs. Balance-filled, low-gradient alkaline lakes would have the best chance of producing an extensive stromatolite record. Overfilled alkaline lakes may deposit thick stromatolite successions that are primarily restricted to the basin margins.
  • ISOTOPE GEOCHEMISTRY OF 2.7 GA CHERT AND CARBONATE, TUMBIANA FORMATION, AUSTRALIA: IMPLICATIONS FOR LATE ARCHEAN CLIMATIC TEMPERATURES AND EARLY EVOLUTION OF LIFE KNAUTH, L. Paul, School of Earth and Space Exploration, Arizona State University, Box 871404, Tempe, AZ 85287-1404, Knauth@asu.edu, AWRAMIK, S.M., Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA 93106, and BUCHHEIM, H. Paul, Earth and Biological Sciences, Loma Linda University, Loma Linda, CA 92350, 2006 Philadelphia Annual Meeting (22–25 October 2006) General Information for this Meeting ( 10/2006 ) Link...
    The most 18O depleted carbonates and cherts in the geologic record are found in the 2.7 Ga Tumbiana Formation in Western Australia. δ18O for carbonate averages about -17.5‰ (literature and new data) and ranges from -26.6‰ to -8.3‰ (PDB). Chert ranges from +11.6‰ to +15‰ (SMOW). Although extraordinarily low in 18O, chert in this unit has the highest δD (-31‰ to -22‰, SMOW) measured for chert of any age. No known metamorphic or late diagenetic alteration process can account for the low δ18O except for shallow hydrothermal alteration in the presence of meteoric waters. However, there are no cross-cutting veins, deformation, metamorphic minerals, or any other geologic evidence of hydrothermal alteration in the rocks examined. Indeed, the Tumbiana Formation is one of the least altered Archean sedimentary units known. High δD in the cherts precludes low18O glacial melt waters as diagenetic fluids. Therefore, the simplest explanation is that the Tumbiana Formation was deposited and stabilized in a late Archean lake, consistent with some (but not all) available sedimentologic interpretations. Even with low 18O lake waters, however, the δ18O values are so low that temperatures in excess of 50°C are required. δ13C is relatively uniform near 0.0 ‰ but ranges between -4.0‰ to +1.9‰ (PDB), suggesting equilibration of lake waters with atmospheric CO2 and absence of significant input of terrestrial photosynthetic C. Abundant and pervasive stromatolites, organic material, and at least one good microfossil occurrence suggest that life was thriving in this environment. Contemporaneous and older Archean marine units described so far do not show comparable evidence of such biological intensity. Taken together, the existing data suggest that the previously inferred high temperatures for the early Archean (Knauth and Lowe, 2003) persisted to at least 2.7 Ga and are consistent with the hypothesis (Knauth, 2005) that early evolution was most active in non-marine environments.
  • Nyborg, T. and H.P. Buchheim. "Depositional environment, tectonics, and animal track distribution of the Neogene fluvial-lacustrine Copper Canyon Unit, Death Valley National Park." 2005 Salt Lake City Annual Meeting (October 16–19, 2005) ( 10/2005 ) Link...
    Extremely well preserved mammal and bird tracks occur throughout the fluvial-lacustrine deposits of the Copper Canyon Unit (CCU). The CCU consists of carbonates, evaporates, shales, claystones, siltstones, sandstones, conglomerates and basalt flows exposed within Copper and Coffin Canyons, Black Mountains, Death Valley National Park. The sequence includes over 3000 meters of basin sediments deposited in a tectonic setting involving large magnitude extension, normal faulting, basin formation, deposition, and subsequent uplift. The CCU can be divided into a fanglomerate, fluvial-lacustrine and basalt members. The fluvial-lacustrine member can be further divided into: evaporite facies; bioclastic carbonate facies consisting of ostracod and gastropod packstone within a calcitic micrite; conglomerate/sandstone facies; and carbonate mudstone facies that contain animal tracks, ripples, raindrops, mudcracks and other shoreline features. The lower sub-unit deposits are dominated by claystones and debris flows reflecting initial fluvial-lacustrine deposits. Up section within the lower middle sub-unit, the claystones are replaced by evaporite facies, reflecting hypersaline standing water conditions and evaporation. Further up section within the middle sub-unit the evaporite facies become rare and carbonate mudstone facies are prominent. Within the upper sub-unit bioclastic carbonate facies are prominent and beds of limestone with tufa mounds suggest spring outlets into a freshwater lake. Track distribution appears to be almost exclusive of the middle sub-unit. New age constraints confirm that the Copper Canyon Unit was deposited approximately between 6 to 3Ma, with track bearing units deposited between 5 to 4Ma. Lithology changes, along with lateral interfingering of fanglomerates within the fluvial-lacustrine member, may reflect lake system changes due to transgressions/regressions, subsidence rates, precipitation/evaporation ratio and/or regional climate changes. Additional mapping, rock analysis and track distribution models will help reconstruct the CCU depositional environment, aiding in the reconstruction of Death Valley''s environment that, approximately 5 million years ago, supported an animal fauna of at least thirty-six species of cat, camel, horse, mastadon and birds.
  • Paul Buchheim and Alan Carroll. "Lacustrine Records of Laramide Landscape Evolution, Green River Formation." Geological Society of America Field Trip. Rock Springs, Wyoming ( 10/2005 ) Link...
  • Buchheim, H. Paul, Biaggi Roberto E., and Cushman, Robert A., II.. "Evolution of Fossil Lake, Wyoming during deposition of the Eocene Green River Formation.." Geological Society of America Annual Meeting. Denver, CO ( 11/2004 ) Link...
  Research Presentations -- Regional
  • SPENCER, Rodney S., LEGGITT, V. Leroy2, and BUCHHEIM, H. Paul2, PALEOENVIRONMENTS OF MIOCENE LAKE BARSTOW: BLACK CANYON, CALIFORNIA, Cordilleran Section (104th Annual) and Rocky Mountain Section (60th Annual) Joint Meeting (19–21 March 2008) ( 3/2008 )
    Silicified microcrustaceans (fairy shrimp, copepods) were recently reported from Black Canyon in the northwest corner of Miocene Lake Barstow. This study compares the paleoenvironment associated with these new fossils with the paleoenvironment of a similar slicified arthropod fauna that occurs in the Calico Mountains (about 55 km southeast of Black Canyon). At both study sites, the silicified fossils occur within early diagenetic carbonate concretions. In order to evaluate the Black Canyon paleoenvironment, petrographic and XRD analysis was performed on individual rock units. Stable isotope analysis (oxygen and carbon) was conducted on primary lake carbonates (micrites) and on the early diagenetic concretions. Calcite was the only carbonate mineral phase observed. Zeolites (clinoptilolite, phillipsite) and gypsum occur in the sediments associated with the concretions. Oxygen stable isotope values varied between -8.6 and -0.8‰ (VPDB). No covariance between oxygen and carbon stable isotope values was observed. In general, the sedimentologic and geochemical results from Black Canyon mirror the sedimentologic characteristics previously reported from the Calico Mountains. Lacustrine sediments at both sites were deposited contemporaneously and under similar paleoenvironmental conditions in a hydrologically closed, saline/alkaline lake that periodically experienced evaporative conditions.
  Poster Presentation
  • Lacustrine Stromatolites and Microbialites as Petroleum Reservoirs Buchheim, Paul (1); Awramik, Stanley (2); Leggitt, Leroy (1) Department of Earth and Biological Sciences, Loma Linda University, Loma Linda, CA. (2) Department of Earth Science, University of California, Santa Barbara, CA.  AAPG Search and Discover Article #90104©2010 AAPG Annual Convention and Exhibition-11-14 April 2010 ( 4/2010 ) Link...
  • Leggitt, V.L., Buchheim, H.P., Cushman, R.A., Jr.. "Crocodilian eggshell fragments encased in stromatolites from the Laney Member of the Green River Formation: Eocene Lake Gosiute." Ancient Life and Modern Approaches. Abstracts of the second international paleontological congress . (2006): 149-.. Beijing, China ( 6/2006 )
  • Nyborg, T. and H.P. Buchheim. "Cenozoic fossil vertebrate tracks of the Copper Canyon Unit, Death Valley National Park, California, USA." Second International Paleontological Conference. Beijing, China ( 6/2006 )
  • Mayry, Matthew, and Buchheim, H. Paul. "GEOCHEMICAL AND SEDIMENTOLOGICAL RECORDS OF LACUSTRINE-SPRING INTERACTIONS: A LARGE SPRING MOUND OF THE EOCENE GREEN RIVER FORMATION." Geological Society of America Annual Meeting. Salt Lake City, Utah ( 10/2005 ) Link...
  Presentations given to non-academic audiences
  • H. Paul Buchheim. "Report on the American Iris Society National Convention." Inland Region Iris Society. Riverside, CA ( 6/2006 )
  • H. Paul Buchheim. "Ancient Lakes of Wyoming." Yuciapi Rock and Mineral Society. Yucaipi, CA ( 2/2006 )