Department of Earth Sciences

Permanent URI for this community

https://hdl.handle.net/1794/9581

Beginning September 1, 2016 the department changed its name from the Department of Geological Sciences to the Department of Earth Sciences.

Browse

Now showing 1 - 20 of 32

Open Access
A Comparison of the Clarendonian Equid Assemblages from the Mission Pit, South Dakota and Ashfall Fossil Beds, Nebraska
(University of Nebraska - Lincoln, 2011-11) Famoso, Nicholas; Pagnac, Darrin
The Mission Pit locality (SDSM V5314), near Mission, South Dakota, has produced a large collection of equid teeth obtained from the Miocene Ash Hollow (=Thin Elk) Formation. Ashfall Fossil Beds (UNSM Ap-116), near Royal, Nebraska, has yielded an extensive collection of equid cranial elements and teeth derived from the Cap Rock Member, Ash Hollow Formation. The two sites are interpreted to be Clarendonian in age [12.5 to 9.0 Ma], but may contain faunal assemblages from differing Clarendonian subages. The two sites exhibit a notably similar composition of equid genera, including the tribes Equini (Pliohippus, Calippus, and Protohippus), and Hipparionini (Cormohipparion, Neohipparion, and Pseudhipparion). Both sites share the same proportion of the equid tribes Hipparionini and Equini. Approximately seventy-five percent of the equids at both sites are members of the Hipparionini tribe, whereas twenty-five percent are of the Equini tribe. The comparative composition within the Equini tribe between the two sites is nearly identical with differences in the absence of Calippus at Ashfall and a larger proportion of Protohippus at Mission. Only slight differences are observed in the composition of genera within the Hipparionini tribe between the two sites, with the Mission Pit containing a higher percentage of Neohipparion. The striking taxonomic similarity between the two sites is not only unique but also rare, suggesting a correlative relationship within the early to medial Clarendonian (Cl1 or Cl2). This similarity also suggests unique paleoecological relationships among equids and has a potential for insight into plant ecology and equid niche partitioning during this time interval.
Open Access
Accumulation of radiocarbon in ancient landscapes: A small but significant input of unknown origin
(Nature Communications, 2023-05-08) Broz, Adrian; Aguilar, Jerod; Xu, Xiaomei; Silva, Lucas C. R.
The persistence of organic carbon (C) in soil is most often considered at timescales ranging from tens to thousands of years, but the study of organic C in paleosols (i.e., ancient, buried soils) suggests that paleosols may have the capacity to preserve organic compounds for tens of millions of years. However, a quantitative assessment of C sources and sinks from these ancient terrestrial landscapes is complicated by additions of geologically modern (~ 10 Ka) C, primarily due to the infiltration of dissolved organic carbon. In this study, we quantified total organic C and radiocarbon activity in samples collected from 28- to 33-million-year-old paleosols that are naturally exposed as unvegetated badlands near eastern Oregon’s “Painted Hills”. We also used thermal and evolved gas analysis to examine the thermodynamic stability of different pools of C in bulk samples. The study site is part of a ~ 400-m-thick sequence of Eocene–Oligocene (45–28 Ma) paleosols, and thus we expected to find radiocarbon-free samples preserved in deep layers of the lithified, brick-like exposed outcrops. Total organic C, measured in three individual profiles spanning depth transects from the outcrop surface to a 1-m depth, ranged from 0.01 to 0.2 wt% with no clear C-concentration or age-depth profile. Ten radiocarbon dates from the same profiles reveal radiocarbon ages of ~ 11,000–30,000 years BP that unexpectedly indicate additions of potentially modern organic C. A two-endmember mixing model for radiocarbon activity suggests that modern C may compose ~ 0.5–2.4% of the total organic C pool. Thermal and evolved gas analysis showed the presence of two distinct pools of organic C, but there was no direct evidence that C compounds were associated with clay minerals. These results challenge the assumption that ancient badland landscapes are inert and “frozen in time” and instead suggest they readily interact with the modern C cycle.
Open Access
Are Hypsodonty and Occlusal Enamel Complexity Evolutionarily Correlated in Ungulates?
(Journal of Mammalian Evolution, Springer Link, 2015-05-13) Famoso, Nicholas; Davis, Edward Byrd; Feranec, Robert S.; Hopkins, Samantha S. B.; Price, Samantha A.
The spread of grasslands and cooling climate in the Miocene contributed to an increasingly abrasive diet for ungulates. This increase in abrasiveness is proposed to select for both hypsodonty and increasing complexity of occlusal enamel bands. If these traits evolved in response to strong selection to resist tooth wear while feeding in grassland habitats, we might expect them to have evolved in a correlated fashion. If, on the other hand, there was a developmental or physiological constraint, or if selection was not strong on total enamel production, we would expect species to have evolved one or the other of these traits at a time, producing an uncorrelated, or even inversely correlated, pattern of trait evolution. To test these hypotheses, we examined the Occlusal Enamel Index (OEI) and Hypsodonty Index (HI) of 773 ungulate teeth. We tested the dependence of OEI on HI for the orders Artiodactyla and Perissodactyla using phylogenetic generalized least squares regression (PGLS). The two traits are not significantly correlated in the PGLS, for Artiodactyla and Perissodactyla. Despite their physical proximity, close functional utility, and conventional correlation, our results reject the hypothesis that HI and OEI are evolutionarily linked in these lineages, suggesting that selection to resist tooth wear was not so strong as to drive the overall evolutionary trajectory of both these traits at the same time.
Open Access
Correction to the holotype (AMNH FM 9394) of Merychippus proparvulus Osborn, 1918 (Perissodactyla, Equidae)
(Journal of Vertebrate Paleontology, 2014-09-09) Famoso, Nicholas; Hopkins, Samantha S.B.
"Correction to the holotype (AMNH FM 9394) of Merychippus proparvulus Osborn, 1918 (Perissodactyla, Equidae)." Journal of Vertebrate Paleontology, 34(5), pp. 1249–1250
Restricted
Data for Cenozoic paleoclimate on land in North America
(University of Oregon, 2016-04) Retallack, Greg J.
Paleotemperature and paleoprecipitation over the past 40 m.yr. can be inferred from the degree of chemical weathering and depth of carbonate nodules in paleosols of Oregon, Montana, and Nebraska. Paleosol records show that late Eocene (35 Ma), middle Miocene (16 Ma), late Miocene (7 Ma), and early Pliocene (4 Ma) warm climatic episodes were also times of a wet climate in Oregon, Montana, and Nebraska. Oregon and Nebraska were humid during warmwet times, but Montana was no wetter than subhumid within the rain shadow of intermontane basins. Global warmwet paleoclimatic spikes steepened rather than flattened geographic gradients of Rocky Mountain rain shadows. Longlived mountain barriers created dusty dry basins with sedimentation rates high enough to preserve Milankovitch-scale (100–41 kyr) global paleoclimatic variation in some sequences of paleosols. Greenhouse warm-wet climates indicated by paleosols were also peaks of diversity for North American plants and animals and coincided with advances in coevolution of grasses and grazers. Paleosol records differ from global compilations of marine foraminiferal oxygen and carbon isotopic composition, due to competing influences of global ice volume and C4 grass expansion. Paleosol records support links between global warming and high atmospheric CO2.
Open Access
Direct measurement of optical properties of glacier ice using a photon-counting diffuse LiDAR
(Cambridge University Press, 2022-04) Allgaier, Markus; Cooper, Matthew G.; Carlson, Anders E.; Cooley, Sarah W.; Ryan, Jonathan C.; Smith, Brian J.
The production of meltwater from glacier ice, which is exposed at the margins of land ice during the summer, is responsible for a large proportion of glacier mass loss. The rate of meltwater production from glacier ice is especially sensitive to its physical structure and chemical composition which combine to determine the albedo of glacier ice. However, the optical properties of near-surface glacier ice are not well known since most prior work has focused on laboratory-grown ice or deep cores. Here, we demonstrate a measurement technique based on diffuse propagation of nanosecond-duration laser pulses in near-surface glacier ice that enables the independent measurement of the scattering and absorption coefficients, allowing for a complete description of the processes governing radiative transfer. We employ a photon-counting detector to overcome the high losses associated with diffuse optics. The instrument is highly portable and rugged, making it optimally suited for deployment in remote regions. A set of measurements taken on Crook and Collier Glaciers, Oregon, serves as a demonstration of the technique. These measurements provide insight into both physical structure and composition of near-surface glacier ice and open new avenues for the analysis of light-absorbing impurities and remote sensing of the cryosphere.
Open Access
Discovery of Oligocene-aged mammals in Glacier National Park (Kishenehn Formation), Montana
(Geodiversitas, 2024-06-24) Famoso, Nicholas; Calede, Jonathan J., 1988-; Kehl, Winifred A.; Constenius, Kurt N.
The Kishnehn Formation crops out in Glacier National Park of northwest Montana where a rich fossil record of plant macrofossils, pollen and spores, insects, terrestrial and aquatic mollusks, and fish has been unearthed. Past research has also described an extensive mammal fauna from the Eocene (Uintan-Chadronian). Oligocene-aged fossil mammals have been reported before, but none has ever been published in the peer-reviewed literature. Here, we present the first Arikareean-aged fossil mammals from the Kishenehn Formation, the youngest fossil mammals ever discovered in the park. The fossils consist of a set of lower jaws of the leptomerycid Pronodens transmontanus (Douglas, 1903) and a partial lower jaw of the rodent Paciculus montanus Black, 1961, both endemics of the northern Rocky Mountains. These new fossils enable us to explore the morphological variation in Pronodens Koerner, 1940 and Paciculus Cope, 1879. Our analyses suggest the existence of a single widely distributed and sometimes locally abundant species of Pronodens, which may co-occur with a rare and very large second species. Our revised diagnoses for the genus and species show the need for additional work on this little-studied artiodactyl genus. Similar efforts on the systematics of cricetid rodents will benefit from building upon our analysis of tooth morphology in Paciculus to shed light on the rise of leidymines. The last fossil we describe, partial paired dentaries of Miohippus Marsh, 1874, is the northern-most occurrence of the genus in the Rocky Mountains and shows the potential for future work in the Kishenehn Formation to enable the study of faunal change across the Eocene-Oligocene boundary in the northern Rocky Mountains.
Open Access
First mesonychid from the Clarno Formation (Eocene) of Oregon, USA
(Palaeontologia Electronica, 2019-06) Robson, Selina V.; Famoso, Nicholas; Davis, Edward Byrd; Hopkins, Samantha S.B.
A recently identified left dentary of Harpagolestes cf. uintensis represents the first mesonychid material known from the Pacific Northwest. The specimen is from the Hancock Quarry (Clarno Unit, John Day Fossil Beds National Monument), which is in the uppermost subunit of the Clarno Formation (middle Eocene, ~40 Ma). The sediments of the Hancock Quarry were deposited by a meandering river system during the middle Eocene when north-central Oregon had a subtropical climate. As with many other mammals from the Hancock Quarry, Harpagolestes participated in an Asian-North American faunal interchange; species of Harpagolestes are known from the Eocene of both continents. Harpagolestes was carnivorous, and members of the genus were likely bone-crushers. Characteristic bone-crushing wear is visible on the occlusal surfaces of the Hancock Quarry specimen’s premolars and molars. With the aid of CT scans, it has been determined that the Hancock Quarry Harpagolestes contains the alveoli for c1, p1-2, and m3, and preserves the crowns of p3-4 and m1-2. The molariform teeth have a large, conical trigonid with a bulbous talonid. The protoconid of p3 and p4 is tilted posteriorly. This specimen of Harpagolestes cf. uintensis represents a new large carnivore in the Hancock Quarry ecosystem, adds to the known diversity of the Oregon middle Eocene, and is the only known occurrence of a mesonychid in the Pacific Northwest.
Open Access
First occurrences of Palaeogale von Meyer, 1846 in the Pacific Northwest, United States
(Geodiversitas, 2022-04-08) Famoso, Nicholas; Orcutt, John D.
The feliform carnivoran Palaeogale von Meyer, 1846 first appears in the Eocene of North America and had a Holarctic distribution in the Oligocene and early Miocene. Despite its large range, Palaeogale has not previously been reported from the Pacific Northwest of North America. We report three new specimens from the John Day Basin of Oregon that fill in this geographic gap. The oldest of these is a largely complete cranium from the Turtle Cove Member of the John Day Formation (Oligocene, 30.0-28.9 Ma). The other two specimens are a left and a right dentary from separate individuals, both recovered from the Kimberly Member (Oligocene, 25.3-23.5 Ma). Because Palaeogale species are almost entirely distinguished by their lower dentition, the cranium cannot be identified to species. However, the cranium is the oldest occurrence of the genus in the Pacific Northwest. The absence of a posterior accessory cusp on the p4 and of lateral expansion of the m1 protoconid allows the dentaries to be assigned to an endemic North American species, P. dorothiae MacDonald, 1963. This is not only the first instance of this species in the Pacific Northwest and outside of South Dakota and Nebraska, but also the last known occurrence of P. dorothiae. We expect that these specimens will inform future analyses of phylogenetics, systematics, morphology, and biogeography in Palaeogale.
Open Access
From public lands to museums: The foundation of U.S. paleontology, the early history of federal public lands and museums, and the developing role of the U.S. Department of the Interior
(The Geological Society of America Special Papers, 2018-11-27) Liggett, Gregory A.; Childs, S. Terry; Famoso, Nicholas; McDonald, Gregory H.; Titus, Alan L.; Varner, Elizabeth; Liggett, Cameron L.
Today, the United States Department of the Interior manages 500 million acres of surface land, about one-fifth of the land in the United States. Since enactment of the Antiquities Act in 1906, historic and scientific resources collected on public land have remained government property, held in trust for the people of the United States. As a result, the Department of the Interior manages nearly 204 million museum objects. Some of these objects are in federally managed repositories; others are in the repositories of partner institutions. The establishment of the United States as a nation corresponded with the development of paleontology as a science. For example, mastodon fossils discovered at or near present-day Big Bone Lick State Historic Site, Kentucky, found their way to notable scientists both in the United States and in Europe by the mid-eighteenth century and were instrumental in establishing the reality of extinction. Public land policies were often contentious, but generally they encouraged settlement and use, which resulted in the modern pattern of federal public lands. Continued investigation for fossils from public land filled the nation’s early museums, and those fossils became the centerpieces of many museum exhibitions. Case studies of the management of fossils found in Fossil Cycad National Monument, the John Day fossil beds, the Charles M. Russell National Wildlife Refuge and surrounding areas of public land, the American Falls Reservoir, and Grand Staircase– Escalante National Monument are outlined. These examples provide a sense of the scope of fossils on federal public land, highlight how their management can be a challenge, and show that public land is vital for continued scientific collection and research.
Open Access
Guidebook: SVP Field Symposium 2010 John Day Basin Field Conference
(2010-04) Fremd, Theodore J.; Society of Vertebrate Paleontology
This guide was developed for a three day field symposium sponsored by the Society of Vertebrate Paleontology. It is intended as an informal, casual guide for participants, and is largely targeted at the graduate student level but is also easily accessible to the nonspecialists. The first SVP field trip guidebook to the John Day Basin was published over 15 years ago, and has been reprinted four times. Although this is a completely new, updated, and considerably expanded revision, some material from the original guide has been incorporated into this one, including the popular “Historical Perspective” sidebars. This guide serves as an "overview" to several of the principal vertebrate fossil localities in the region. Complete coverage of the extensive fossiliferous strata in this basin, with numerous Eocene through Pliocene assemblages spanning forty Ma, deposited in several widely separated basins, is beyond the scope of this short contribution (see the Introduction). This version updates and serves as a replacement for the above noted earlier field guide.
Open Access
How do diet and body mass drive reproductive strategies in mammals?
(Biological Journal of the Linnean Society, 2018-04-19) Famoso, Nicholas; Hopkins, Samantha S.B.; Davis, Edward Byrd
Larger body size tends to lead to lower reproductive rates in mammals, but we do not understand how diet impacts this relationship. Reproductive strategies vary from K-selected (producing few offspring with extensive parental care) to r-selected (producing many offspring with little parental care). Here, we investigate how diet and body size impact the reproductive strategies of mammals within a phylogenetic framework using an index for reproductive strategy. For all diet categories we find larger mammals to be more K-selected. This relationship is significant for herbivores and omnivores, but not for carnivores, although the relationship for carnivores is comparable to that of herbivores and omnivores. The relationship is non-linear in carnivores and may be a consequence of differences between insect and vertebrate predators. Ultimately, the trend of more K-selected strategies with larger body size holds true for herbivores and omnivores, but different trajectories exist for carnivores depending on diet.
Open Access
Inequalities of ice loss: a framework for addressing sociocryospheric change
(Cambridge University Press, 2023-05-12) Carey, Mark; Moulton, Holly
Cryospheric change occurs in unequal spaces. Societies living near ice are divided by race, class, gender, geography, politics and other factors. Consequently, impacts of ice loss are not shared equally, and everyone experiences cryospheric changes differently. Responsibility for recent ice loss is also driven by a relatively small portion of humanity: those who emit the most greenhouse gases. Additionally, people who study the cryosphere come from institutions and societies where inequality is often systemic, making research on ice and snow a symptom of and contributor to social inequality. To better understand unequal effects of cryospheric change within and across diverse communities, including research communities, this paper focuses on three areas, drawing primarily from glacier-related work: (1) the social context of cryospheric changes; (2) attribution and responsibility for cryospheric changes and (3) imbalances in knowledge about the cryosphere. Addressing these dimensions of ice loss requires transdisciplinary approaches that connect research to societies and link glaciology and other cryospheric sciences with social sciences and humanities. These concepts, cases and suggestions to help address inequalities also reveal that no singular conceptualization of sustainability exists. Different societies, residents and researchers possess distinct understandings of and goals for ‘ice in a sustainable society’.
Open Access
The largest hoplophonine and a complex new hypothesis of nimravid evolution
(Nature Research, 2021-10) Barrett, Paul Zachary
Nimravids were the first carnivorans to evolve saberteeth, but previously portrayed as having a narrow evolutionary trajectory of increasing degrees of sabertooth specialization. Here I present a novel hypothesis about the evolution of this group, including a description of Eusmilus adelos, the largest known hoplophonine, which forces a re-evaluation of not only their relationships, but perceived paleoecology. Using a tip-dated Bayesian analysis with sophisticated evolutionary models, nimravids can now be viewed as following two paths of evolution: one led to numerous early dirk-tooth forms, including E. adelos, while the other converged on living feline morphology, tens of millions of years before its appearance in felids.
Open Access
Mammalian community response to historic volcanic eruptions
(Mammalian Biology, 2020-03-09) Famoso, Nicholas
It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. Volcanic eruptions vary with magnitude and type and only a fraction of them have been analysed for effects on mammalian communities. To better understand mammalian community recovery, I investigated how species richness, evenness, and similarity change across volcanic boundaries in the 1980 Mount Saint Helens (MSH), Washington, and 1914–1917 Mount Lassen, California, eruptions. I compared these eruptions to Mount Rainier, Washington and Mount Shasta, California as controls for regional changes in the fauna. Richness and evenness remain relatively unchanged in Lassen. MSH saw an immediate drop in richness, followed by an increase over 5 years to pre-eruptive levels. Chord distance analysis suggests no long-term change in the Lassen fauna. The pre- and post-MSH fauna are different from one another. The post-eruptive fauna was more similar to neighbouring regions. It is clear from my results that larger eruptions tend to have a greater impact on mammalian community recovery than smaller eruptions, but ultimately, mammalian populations are robust and the presence of neighbouring communities is important for recolonizing devastated areas.
Open Access
Microtomography of an enigmatic fossil egg clutch from the Oligocene John Day Formation, Oregon, USA, reveals an exquisitely preserved 29-million-year-old fossil grasshopper ootheca
(Parks Stewardship Forum, 2024) Lee, Jaemin; Famoso, Nicholas; Lin, Angela
Eggs are one of the least understood life stages of insects, and are poorly represented in the fossil record. Using microtomography, we studied an enigmatic fossil egg clutch of a presumed entomological affinity from the Oligocene Turtle Cove Member, John Day Formation, from the National Park Service-administered lands of John Day Fossil Beds National Monument, Oregon. A highly organized egg mass comprising a large clutch size of approximately 50 slightly curved ellipsoidal eggs arranged radially in several planes is preserved, enclosed in a disc-shaped layer of cemented and compacted soil particles. Based on the morphology of the overall structure and the eggs, we conclude that the specimen represents a fossilized underground ootheca of the grasshoppers and locusts (Orthoptera: Caelifera), also known as an egg pod. This likely represents the oldest and the first unambiguous fossil evidence of a grasshopper egg pod. We describe Subterroothecichnus radialis igen. et isp. nov. and Curvellipsoentomoolithus laddi oogen. et oosp. nov., representing the egg pod and the eggs, respectively. We advocate for adopting ootaxonomy in studying fossil eggs of entomological affinities, as widely practiced with fossil amniotic eggs. An additional 26 individual and clustered C. laddi collected throughout the A–H subunits of the Turtle Cove Member suggest the stable presence of grasshoppers in the Turtle Cove fauna, and we discuss the paleoecological implications. Oothecae have convergently evolved several times in several insect groups; this ovipositional strategy likely contributed to the fossilization of this lesser-known ontogenetic stage, enriching our understanding of past insect life.
Open Access
Morphological Proxies for Fossoriality, Supplementary Appendices
(2009-08-20T17:10:34Z) Hopkins, Samantha; Davis, Edward Byrd
Supplementary Appendices from Hopkins and Davis 2009, Journal of Mammalogy. Appendix I: Taxonomy, ecological data, and morphological characters from 123 species representing 15 of the 29 orders of extant mammals, used for discriminant analysis. Appendix II: Eigenvectors from discriminant analyses.
Open Access
Mount Multnomah: Ancient Ancestor of the Three Sisters
(University of Oregon, 1925-08-01) Hodge, Edwin T.
Open Access
New occurrences of mammals from McKay Reservoir (Hemphillian, Oregon)
(Journal of Paleontology, 2024-05-07) Orcutt, John D.; Schmer, Christiana J.; Lubisich, Jeffrey P.; Abrams, Lacy T.; Famoso, Nicholas
Encompassing global cooling, the spread of grasslands, and biogeographic interchanges, the Hemphillian North American Land Mammal Age is an important interval for understanding the factors driving ecological and evolutionary change through time. McKay Reservoir near Pendleton, Oregon is a natural laboratory for analyses of these factors. It is remarkable for its small vertebrate fauna including rodents, bats, turtles, and lagomorphs, but also for its larger mammal fossils like camelids, rhinocerotids, canids, and felids. Despite the importance of the site, few revisions to its faunal list have been published since its original description. We expand on this description by identifying taxa not previously known from McKay Reservoir based on specimens collected during fieldwork and through reidentification of previously collected fossils. Newly identified taxa include the borophagine canid Borophagus secundus (Matthew and Cook, 1909), the camelids Megatylopus Matthew and Cook, 1909 and Pleiolama Webb and Meachen, 2004, a dromomerycid, and the equids Cormohipparion Skinner and MacFadden, 1977 and Pseudhipparion Ameghino, 1904. Specimens previously assigned to Neohipparion Gidley, 1903 and Hipparion de Christol, 1832 lack the features necessary to diagnose these genera, which are therefore removed from the site's faunal list. The presence of Borophagus secundus, Cormohipparion, and Pseudhipparion is especially important, because each occurrence represents a major geographic range extension. This refined understanding of the fauna lays the foundation for future studies of taphonomy, taxonomy, functional morphology, and paleoecology—potentially at the population, community, or ecosystem levels—at this paleobiologically significant Miocene locality.
Restricted
Northern Goshawks in the Malheur National Forest Eastern Oregon 1992 TO 2011
(2012-05-02) Rickabaugh, Skylar J.; Fremd, Theodore J.
This report summarizes the data generated from a long-term effort to perform continued and consistent monitoring of goshawk nest sites on the Malheur National Forest in eastern Oregon from 1992 to 2010. This compilation is the product of personal field work in which data were collected in a manner that was consistent with the methods developed in 1992, the first year in which attempts to quantify variables in territory usage, habitat selection, yearly productivity, and other behavioral attributes of Northern Goshawk (Accipiter gentilis) began in the drier eastern forests of Oregon. The contents of this manuscript consist of a narrative of the history of studies and methods as envisioned by researchers from Oregon State University and various public land management agencies, and the yearly field observations subsequently carried out by the author. This information includes the tracking of movement, productivity, and yearly occurrences of goshawk in their territories, along with other observations and studies that were added by the author. Rather than viewing this as an attempt to test hypotheses, this is a presentation of a long- term monitoring project, in the mold of classic natural history observations. This manuscript contains specific data and information from insights that hopefully will be gleaned to aid further investigations in this region of eastern Oregon, and may be of interest elsewhere.

Browse

Browsing Department of Earth Sciences by Title

Results Per Page

Sort Options