Snow Hill Research Articles

DIGITISING SENSITIVE HERITAGE MONUMENTS IN ANTARCTICA

Abstract. During the Antarctica expedition CHAQ2020, several cultural heritage sites – remains from the Swedish South Polar Expedition (1901–1903) – were documented using a range of different techniques and technologies. These physical monuments and environments are for all intents and purposes unavailable for most researchers due to their remote location and are also threatened by the effects of climate change. Hence, the deployed documentation techniques and technologies were selected both as a consequence of the inherently difficult conditions in Antarctica, where their reliance, durability, and speed were key considerations, but also for their perceived ability to document the unique and fragile environment. The documentation was carried out with the double intention of both allowing for observations in situ through processes of analytical drawings and data capture, but also capturing the environment as broadly and deeply as possible, in essence making a copy of it open for studies of unknown unknowns, that could serve as a source material for research questions still undefined. Hence, with the documentation of the winter station on Snow Hill Island as a case study, and with a perspective on documentation as a method through which to process, preserve, and disseminate information, this article serves to critically detail, compare, and evaluate the digital techniques and technologies that the expedition deployed to capture architectural elements and spatial contexts, and the data that could be obtained through these.

And the Mural Came Down: Race, Removal, and Reckoning in the Sunshine City

In 1966 Joseph Waller and other members of the Student Nonviolent Coordinating Committee removed George Snow Hill’s Picnicking at Pass-a-Grille (1945) from St. Petersburg, Florida’s, City Hall. For more than two decades, the mural had hung alongside its pendant, Hill’s Fishing on the Pier (1945). Together, the paintings offered a vision of civic progress that denied Black audiences full participation in public life. Yet even in its absence, Picnicking at Pass-a-Grille troubles the present. The Sunshine City’s deferred reckoning with its public artworks and urban projects of racial oppression is a local history with national resonances.

New records of hexanchiform sharks (Elasmobranchii: Neoselachii) from the Late Cretaceous of Antarctica with comments on previous reports and described taxa

ABSTRACT Sharks are virtually absent from coastal Antarctica since the Late Eocene glaciations, but this group exhibited a notable austral diversity during the Cretaceous and Paleogene. Several species have already been described from the Aptian-Eocene successions of the Larsen Basin exposed in the James Ross Island area (northern Antarctic Peninsula) and the predominantly deep-water Hexanchiformes have a record that, although still rare, has been continually increased. Four species of this group are currently known from that basin: Notidanodon pectinatus, Xampylodon dentatus, Rolfodon thompsoni, and Rolfodon tatere. Such records are especially concentrated in the Gamma Member of the Snow Hill Island Formation (or Herbert Sound Member of Santa Marta Formation), on James Ross Island. Here we described four teeth assigned to X. dentatus and one identified as R. tatere from upper Campanian sections of James Ross Island, highlighting the nomenclatural changes that led to the definition of Xampylodon and Rolfodon. Some specimens of X. dentatus presented here are considerably more complete or represent teeth of different positions than most previous records. The material assigned to R. tatere represents the oldest record of this species in the world, extending its time range by more than 10 million years.

Dinoflagellate cysts from the Upper Cretaceous (Campanian–Maastrichtian) from The Naze Peninsula, James Ross Island, Antarctica

We present the results of the quantitative and qualitative study of dinoflagellate cysts in outcrop samples from a section of the Snow Hill Island Formation (SHF) in James Ross Island, Antarctic. Dinoflagellate cysts assemblages are abundant and dominated by gonyaulacoid taxa. The last occurrence of the dinoflagellate cyst Kallosphaeridium? helbyi and Chatangiella granulifera, together with the first occurrence of Pterodinium cretaceum, indicates a probable late Campanian age (∼76.4–∼72.1 Ma) for the lower strata. Whereas the first occurrence of Manumiella bertodano and the last occurrence of Odontochitina operculata, Xenascus ceratioides, and Stiphrosphaeridium anthophorum indicate an early Maastrichtian (∼72.1–∼70.0 Ma) age for the upper strata. Our results, combined with paleobotanical and palynological published data, indicate medium–high continental and marine productivity with temperate paleoclimate free of glaciers for this interval. Lithological and paleontological data indicate mainly inner neritic marine depositional environments. The predominance of shales in the lower part of the lower Maastrichtian interval indicates a slightly deeper environment. In contrast, in the middle part of the lower Maastrichtian, a shallower, transitional environment is marked by the presence of theropod dinosaurs and decapod crustaceans.

New occurrences of caryophylliid and fungiacyathid scleractinian corals from the Santa Marta and Snow Hill Island formations (Upper Cretaceous, Antarctica)

Scleractinian corals have been reported in the Antarctic Cretaceous since the beginning of the 20th century, but few studies have described the taxonomy of these specimens. Here we describe three new occurrences of coral from the James Ross Basin based on specimens collected in 2016. We identified Dasmosmilia? sp. and Heterocyathus filkorni sp. nov. in the Alpha Member of the Santa Marta Formation on James Ross Island (upper Santonian to lower Campanian) and Fungiacyathus deltoidophorus and a poorly-preserved and unidentifiable scleractinian coral from the Karlsen Cliffs Member of Snow Hill Island Formation (lower Maastrichtian). Heterocyathus filkorni sp. nov. represents the earliest occurrence of this genus in the Southern Hemisphere and is consistent with the hypothesis that a marine exchange between Europe and Antarctica was occurring in the Late Cretaceous. If confirmed, the Dasmosmilia described here represent their earliest record from the Antarctic Cretaceous.

New age constraints support a K/Pg boundary interval on Vega Island, Antarctica: Implications for latest Cretaceous vertebrates and paleoenvironments

AbstractA second K/Pg boundary interval in the northern sector of the Antarctic Peninsula on Vega Island has been proposed, yet current temporal resolution of these strata prohibits direct testing of this hypothesis. To not only test for the existence of a K/Pg boundary on Vega Island but also provide increased age resolution for the associated vertebrate fauna (e.g., marine reptiles, non-avian dinosaurs, and avian dinosaurs), the Vega Island succession was intensively re-sampled. Stratigraphic investigation of the Cape Lamb Member of the Snow Hill Island Formation, and in particular, the overlying Sandwich Bluff Member of the López de Bertodano Formation, was conducted using biostratigraphy, strontium isotope stratigraphy, magnetostratigraphy, and detrital zircon geochronology. These data indicate a Late Campanian–early Maastrichtian age for the Cape Lamb Member and present three possible correlations to the global polarity time scale (GPTS) for the overlying Sandwich Bluff Member. The most plausible correlation, which is consistent with biostratigraphy, detrital zircon geochronology, sequence stratigraphy, and all but one of the Sr-isotope ages, correlates the base of the section to C31N and the top of the section with C29N, which indicates that the K/Pg boundary passes through the top of the unit. A second, less plausible option conflicts with the biostratigraphy and depends on a series of poorly defined magnetic reversals in the upper part of the stratigraphy that also correlates the section between C31N and C29R and again indicates an inclusive K/Pg boundary interval. The least likely correlation, which depends on favoring only a single Srisotope age at the top of the section over biostratigraphy, correlates the section between C31N and C30N and is inconsistent with an included K/Pg boundary interval. Although our preferred correlation is well supported, we failed to identify an Ir-anomaly, spherules/impact ejecta, or other direct evidence typically used to define the precise position of a K/Pg boundary on Vega Island. This study does, however, confirm that Vegavis, from the base of the Sandwich Bluff Member, is the oldest (69.2–68.4 Ma) phylogenetically placed representative of the avian crown clade, and that marine vertebrates and non-avian dinosaurs persisted in Antarctica up to the terminal Cretaceous.

Late Campanian-Early Maastrichtian Vertebrates From The James Ross Basin, West Antarctica: Updated Synthesis, Biostratigraphy, And Paleobiogeography.

The Snow Hill Island Formation (SHIF; late Campanian - early Maastrichtian) crops out in the northeast of the Antarctic Peninsula and constitutes the basal part of the late Campanian-early Maastrichtian sedimentary succession of the James Ross Basin (NG Sequence). Its major exposures occur at the James Ross and Vega islands. Several fossil-bearing localities have been identified in the SHIF providing a valuable fauna of invertebrates and vertebrates, and flora. Our study focuses on the vertebrate fauna recovered at Gamma and Cape Lamb members of the SHIF. The marine vertebrate assemblages include chondrichthyans, actinopterygians, and marine reptiles (elasmosaurid plesiosaurs and mosasaurs). A diverse terrestrial vertebrate assemblage has been reported being characterized by dinosaurs (sauropod, elasmarian ornithopods, nodosaurid ankylosaur, and a paravian theropod), pterosaurs and birds. Most SHIF dinosaurs share close affinities with penecontemporaneous taxa from southern South America, indicating that at least some continental vertebrates could disperse between southern South America and Antarctica during the Late Cretaceous. The Snow Hill Island Formation provides the most diverse Late Cretaceous marine and continental faunas from Antarctica. The present study summarizes previous and new vertebrate findings with the best actualized stratigraphical framework, providing a more complete fauna association and analyzing further perspectives.

Novas ocorrências de moluscos das formações Santa Marta e Snow Hill Island (Membro Gamma), Cretáceo Superior, Ilha James Ross, Península Antártica

Although the fossil record from Antarctica is increasing continuously, there is still a great lack of knowledge regarding the past biodiversity of this continent. Here we present the first occurrences of the ammonoid Pseudophyllites? cf. latus in the Santa Marta Formation (Santonian-early Campanian) and the scaphopod Laevidentallium? sp. (Laevidentallidae) in the Gamma Member (late Campanian) of the Snow Hill Island Formation (late Campanian - early Maastrichtian). The presence of Laevidentalliidae in the Gamma Member characterizes the oldest occurrence of this family in Antarctica and it is apparently another taxon that originated in this continent and later migrated to lower latitudes.

Prostranstvennaya struktura i vnutrigodovaya izmenchivost' fronta morya Ueddella po dannym reanaliza NOAA OISST

Based on the NOAA OISST reanalysis data, the spatial structure of the Weddell Sea Front in the climatic field of the sea surface temperature was analyzed and the seasonal variability of front’s characteristics was estimated. The spatial position of the frontal zone in the Weddell Sea was analyzed using distributions of the total horizontal temperature gradient. The characteristics of the front (the position of the gradients' extrema corresponding to the front, their magnitude and temperature on the front axis) were determined for each month on the profiles of meridional and zonal temperature gradients along meridians and parallels with a discreteness of 2.5° of longitude and 0.25° of latitude. It is shown that the interaction of Weddell Sea cold waters, which are transported by currents northward along the Antarctic Peninsula coasts, with the warmer waters of the eastern shelf of the Antarctic Peninsula and the Bransfield Strait surface water causes formation of two branches of the Weddell Sea Front. These branches round from a vast shelf at the Antarctic Peninsula tip and the Joinville archipelago the south and north and are traced further east along the boundaries of the bottom rise located approximately between 62.5S and 64.5S. To the south of the South Orkney Islands shelf, the two branches merge into one front, which follows to the east along the depth dump of the relative shallow between the South Orkney and South Sandwich Islands. In the seasonal cycle of the Weddell Sea Front intensity, a time lag was revealed of the front intensification period in the direction from west to east. In Bransfield Strait the front is most intense in February, between the Antarctic Peninsula tip and the South Orkney Islands – in March, east of the South Orkney Islands – in April. The branch of the Weddell Sea Front off the northeastern of the Antarctic Peninsula coasts intensifies in November – January, in the western part of the water area east of the James Ross and Snow Hill Islands – in January – February.

Coniacian-Campanian magnetostratigraphy of the Marambio Group: The Santonian-Campanian boundary in the Antarctic Peninsula and the complete Upper Cretaceous – Lowermost Paleogene chronostratigraphical framework for the James Ross Basin

Recent magnetostratigraphic works from different areas of the James Ross Basin have expanded on chronostratigraphic studies previously based on ammonite, palynomorph and nanoplankton biostratigraphy, and strontium isotope stratigraphy. Here we present a new magnetostratigraphy of Coniacian through Campanian marine sedimentary rocks from Hidden Lake, Santa Marta and Snow Hill Island Formations, on northwest James Ross Island. A total of 189 paleomagnetic directions were obtained along more than 1500 m of stratigraphic thickness from Brandy Bay to Santa Marta Cove areas, identifying three polarity chrons of the global polarity time scale. The local magnetostratigraphic column starts in the upper part of the Cretaceous Normal Superchron C34N (Coniacian) and ends in Chron C33N (middle Campanian). The correlation between the magnetostratigraphy and the age framework given by ammonite biostratigraphy allowed the assignment of precise ages to particular horizons of the Santa Marta Formation. The newly identified geomagnetic polarity reversals are the earliest identified in the James Ross Basin and include: a) C34N/C33R (84.2 Ma, late Santonian – early Campanian) in the Alpha Member of the Santa Marta Formation and b) C33R/C33N (79.9 Ma, middle Campanian) in the upper Beta Member (Santa Marta Formation). By integrating this new data with previous work, we present a complete Upper Cretaceous – lowermost Paleogene chronostratigraphical framework for the basin, spanning both proximal to distal sedimentary facies of the Marambio Group.

BOOK REVIEW

A very young man, the first Argentine to explore and work in Antarctica, a man alone in many ways, a man who kept a diary: Jose Maria Sobral (1880–1961) was a member of the Swedish South Polar Expedition (1901–1903) shore party of six men, headed by Professor Otto Nordenskjold, which worked on Snow Hill Island off the tip of the Antarctic Peninsula. His presence among the Scandinavians was a trade-off for the support of the Argentine government, which had supplied food and provisions. Sobral, a 21-year-old under-lieutenant in the Argentine navy, performed expedition work in meteorology

An enigmatic bird from the lower Maastrichtian of Vega Island, Antarctica

We describe a partial skeleton from the lowest Maastrichtian levels of the Snow Hill Island Formation (Vega Island, West Antarctica). Because of the anatomical differences with the Antarctic Vegavis iaai and Polarornis gregorii, this fossil is recognized here as a new genus and species. The results of our phylogenetic analysis suggest that A. capelambensis would be placed inside the Ornithuromorpha, and probably nested within the Ornithurae. This provisional assignment could only be confirmed through the finding of most complete and better preserved specimens. Antarcticavis capelambensis is the geologically oldest bird described from Antarctica.

New evidence of a Campanian age for the Cretaceous fossil-bearing strata of Cape Marsh, Robertson Island, Antarctica

Cape Marsh, located on the eastern end of Robertson Island to the east of the Antarctic Peninsula, exposes an isolated outcrop of Upper Cretaceous sedimentary strata. The outcrop is approximately 120 km southwest of the much better-studied exposures of similar age on and around James Ross Island (JRI); as such, its remoteness has complicated logistical access to the site and hindered geologic correlations on a regional scale. Here we present the results of fieldwork conducted in 2016 that yielded a more diverse invertebrate fossil assemblage than had been previously recognized, in addition to new U–Pb detrital zircon and magnetostratigraphic data. The invertebrate fauna, particularly the ammonites and inoceramids, support a biostratigraphic correlation of the upper Cape Marsh strata to Ammonite Assemblage 7 previously established on JRI. Detrital zircon U–Pb analysis conducted on a sandstone sample from the same strata indicates a maximum depositional age of 74.2 ± 1.1 Ma, and magnetostratigraphic interpretation of the lower strata suggest a normal magnetochron. These results are all consistent with a Campanian age for the deposition of the upper strata at Cape Marsh, and deposition during magnetochron C33N for the lower layers. However, a slight age inconsistency between the biostratigraphic correlation and the detrital zircon-derived maximum depositional age may imply that the fossils are reworked. Regardless, these new data allow us to correlate the strata at Cape Marsh to the Santa Marta and Rabot formations (or possibly the lower part of the Snow Hill Island Formation) in the northern part of the James Ross Basin.

Mid Campanian‐Lower Maastrichtian magnetostratigraphy of the James Ross Basin, Antarctica: Chronostratigraphical implications

AbstractThe James Ross Basin, in the northern Antarctic Peninsula, exposes which is probably the world thickest and most complete Late Cretaceous sedimentary succession of southern high latitudes. Despite its very good exposures and varied and abundant fossil fauna, precise chronological determination of its infill is still lacking. We report results from a magnetostratigraphic study on shelfal sedimentary rocks of the Marambio Group, southeastern James Ross Basin, Antarctica. The succession studied covers a ~1,200 m‐thick stratigraphic interval within the Hamilton Point, Sanctuary Cliffs and Karlsen Cliffs Members of the Snow Hill Island Formation, the Haslum Crag Formation, and the lower López de Bertodano Formation. The basic chronological reference framework is given by ammonite assemblages, which indicate a Late Campanian – Early Maastrichtian age for the studied units. Magnetostratigraphic samples were obtained from five partial sections located on James Ross and Snow Hill islands, the results from which agree partially with this previous biostratigraphical framework. Seven geomagnetic polarity reversals are identified in this work, allowing to identify the Chron C32/C33 boundary in Ammonite Assemblage 8‐1, confirming the Late Campanian age of the Hamilton Point Member. However, the identification of the Chron C32/C31 boundary in Ammonite Assemblage 8‐2 assigns the base of the Sanctuary Cliffs Member to the early Maastrichtian, which differs from the Late Campanian age previously assigned by ammonite biostratigraphy. This magnetostratigraphy spans ~14 Ma of sedimentary succession and together with previous partial magnetostratigraphies on Early‐Mid Campanian and Middle Maastrichtian to Danian columns permits a complete and continuous record of the Late Cretaceous distal deposits of the James Ross Basin. This provides the required chronological resolution to solve the intra‐basin and global correlation problems of the Late Cretaceous in the Southern Hemisphere in general and in the Weddellian province in particular, given by endemism and diachronic extinctions on invertebrate fossils, including ammonites. The new chronostratigraphic scheme allowed us to calculate sediment accumulation rates for almost the entire Late Cretaceous infill of the distal James Ross Basin (the Marambio Group), showing a monotonous accumulation for more than 8 Myr during the upper Campanian and a dramatic increase during the early Maastrichtian, controlled by tectonic and/or eustatic causes.

Observation of the Emperor penguins <i>Aptenodytes forsteri</i> in the Prince Gustav Channel related with unusual sea-ice decline in north-western Weddell Sea

A pair of juvenile emperor penguins (Aptenodytes forsteri) was observed in the northern coast of James Ross Island, the north-western sector of the Weddell Sea, Antarctica, in January 2017. The penguins originated from the colony located on Snow Hill Island, 120-130 km far from the observation area. Despite the emperor penguin´s ability to migrate over long distances, when they are well-known from different areas in Antarctica, this was the first observation of this species in the north of James Ross Island. In this short paper we discuss the environmental factors which allowed the penguins to reach James Ross Island northern coast, especially significant sea ice variability in this area during last decade.

The Sounds of Ephrata: Developing a Research Methodology to Catalog and Study Eighteenth- and Nineteenth-Century Pennsylvanian Music Manuscripts

At least 135 Colonial American music manuscripts from Pennsylvania are located in libraries throughout the United States and beyond. They are affiliated with the Ephrata Cloister, founded in 1732 by Conrad Beissel. Ephrata, and its nineteenth-century affiliated community Snow Hill, were celibate, ascetic, German-speaking, Sabbatarian communes in the wilderness of Pennsylvania. Their residents created a large corpus of hymns and motets in a scriptorium. Because Ephrata and Snow Hill produced no heirs, their documents were scattered and their traditions were mostly forgotten. Although significant strides have been made in recent years to understand Ephrata's theology, substantial lacunae remain in the study of its music.

Pterodactyloid pterosaur bones from Cretaceous deposits of the Antarctic Peninsula.

Fossil vertebrates from Antarctica are considerably rare, hampering our understanding of the evolutionary history of the biota from that continent. For several austral summers, the PALEOANTAR project has been carrying out fieldwork in the Antarctic Peninsula in search for fossils, particularly Cretaceous vertebrates. Among the specimens recovered so far are two bones referable to Pterosauria, more specifically to the Pterodacyloidea, the first volant reptiles from Antarctica to be fully described. MN 7800-V (part and counterpart) was recovered from a moraine at the Abernathy Flats (Santa Marta Formation, Lachman Crags Member, Santonian-Campanian) on James Ross Island. It is interpreted as the distal articulation of a first phalanx of the wing finger, representing an animal with an estimated wingspan between 3 and 4 m. The second specimen (MN 7801-V) comes from Vega Island (Snow Hill Island Formation, Maastrichtian) and is identified as a wing metacarpal IV of an animal with an estimated wingspan from 4 to 5 m. These occurrences show that pterodactyloids inhabited the Antarctic Peninsula at least during the Upper Cretaceous and demonstrate that large pterosaurs were widespread through all parts of the planet during that period.

The first non-aristonectine elasmosaurid (Sauropterygia; Plesiosauria) cranial material from Antarctica: New data on the evolution of the elasmosaurid basicranium and palate

Elasmosaurids are a monophyletic group of cosmopolitan plesiosaurs with extremely long necks. Although abundant elasmosaurid material has been collected from the Upper Cretaceous of Antarctica, skull material is extremely rare. Here, new elasmosaurid cranial material from the lower Maastrichtian levels of the Cape Lamb Member (Snow Hill Island Formation) on Vega Island, Antarctica is described. The studied specimen (MLP 15-I-7-6) is a non-aristonectine elasmosaurid but shows a palate morphology characterized by the absence of a posterior interpterygoid symphysis and a posterior plate-like extension of the pterygoids, features previously associated with the aristonectine palatal structure. The specimen MLP 15-I-7-6 thus provides an indication that these palatal features are also present in non-aristonectine Weddellian elasmosaurids, and makes available additional evidence of the close phylogenetical relationship between the aristonectines and some Weddellian non-aristonectine elasmosaurids.

Gastrointestinal helminths of Emperor Penguin (Aptenodytes forsteri) from Antarctica

Although research on parasitic diseases in Antarctic birds is scarce and the information largely fragmented, an increasing number of studies are currently in progress in this area. The host/parasite relationship is very important for understanding the impact of parasitism on the seabirds’ feeding ecology, especially in those isolated regions where the host is extremely sensitive to new diseases. Penguins are a big favorite for these studies because of their importance as indicators of change in the Antarctic ecosystem. This study aims at adding information on gastrointestinal parasites of the Emperor Penguin Aptenodytes forsteri from Snow Hill colony. Based on a sample of 43 individuals found freshly dead (3 adults and 40 chicks) from predation or starvation, the gastrointestinal helminth community in Emperor penguins was composed of two species of cestodes (Parorchites zederi and Tetrabothrius sp.) and three species of nematodes (Stegophorus macronectes, Tetrameres sp. and Contracaecum osculatum). This is the first record of S. macronectes in the Emperor Penguin. The low parasite richness observed might be related to the stenophagic and pelagic diet of this host.

Stratigraphy, sedimentology and paleontology of Upper Cretaceous deposits of Day Nunatak, Snow Hill Island, Antarctica

Day Nunatak exposes an actively emergent stratigraphic section located on Snow Hill Island to the east of the Antarctic Peninsula. Strata exposed on Snow Hill Island were deposited in the James Ross Basin, which includes marine units of Cretaceous–Paleogene (K–Pg) age. Here we provide the first report of the sedimentology and paleontology of Day Nunatak, and place it into the broader stratigraphic context of the basin. Day Nunatak was previously unexplored due to difficulties accessing the site, and the historically poor exposure which has recently improved due to warming of the Antarctic Peninsula. Deposits exposed at Day Nunatak are assigned to the Karlsen Cliffs Member (KCM) of the Snow Hill Island Formation, and are better preserved than deposits at the type section of the KCM at Karlsen Cliffs, which has been altered by cross-cutting basaltic dikes. Correlation of lithostratigraphic and biostratigraphic data from Day Nunatak with other outcrops in the basin allows the section to be placed within a previously developed stratigraphic framework, and assigned an early Maastrichtian age. Our observations, and previous descriptions of the KCM, are consistent with a middle- to inner-shelf depositional environment below storm-wave base. Ammonites of the genus Gunnarites are very common, with other ammonite genera and benthic mollusks an order of magnitude less common. Stable carbon and oxygen isotope values obtained from bivalve shells are similar to values previously reported from Seymour Island, and suggest seawater temperatures of ∼7 °C. Measured bedding orientations suggest the presence of a structural offset between Day Nunatak and other sections exposed further north on Snow Hill Island. Day Nunatak preserves a similar depositional environment to deposits reported from the uppermost Maastrichtian on Seymour Island, and is the deeper-water equivalent of contemporaneous proximal sections reported from Vega Island.