Latest Devonian–Earliest Mississippian nearshore trace-fossil assemblages from West Virginia, Pennsylvania, and Maryland

1987 ◽  
Vol 61 (5) ◽  
pp. 865-889 ◽  
Author(s):  
Thomas W. Bjerstedt

Trace fossils are used in deposystem analysis of Late Devonian–Early Mississippian nearshore facies in the north-central Appalachian Basin. These nearshore facies resulted from separate transgressions during latest Devonian (Cleveland Shale) and earliest Mississippian (Sunbury Shale) time. Emphasis is placed on a well-exposed section at Rowlesburg, West Virginia, where the Oswayo, Cussewago Sandstone, and Riddlesburg Shale Members of the Price Formation are exposed.The Oswayo Member at Rowlesburg preserves an offshore-to-lower shoreface transition in a complex of euryhaline, protected-bay, lagoon, and possible estuarine facies. Cruziana is common and occurs along with Arthrophycus, Bifungites, Chondrites, Planolites, Palaeophycus, Rhizocorallium, Rosselia, Rusophycus, and Skolithos in intensely bioturbated mudstone, siltstone, and sandstone. These lithologies were deposited below fair-weather wave base and grade upsection to upper shoreface facies comprised of thick, horizontally-laminated sandstones with thinner, burrowed mudstone interbeds. Upper shoreface traces consist of Arenicolites, Cruziana, Diplocraterion, Dimorphichnus, Planolites, Thalassinoides, and Skolithos. Skolithos “pipe rock” sandstones occur at the toe of upper shoreface facies. Eastward the Oswayo Member grades into a restricted-bay facies and finally into beach and tidal flat facies near its stratigraphic wedge-out in eastern West Virginia and western Maryland. The Cussewago Sandstone Member at Rowlesburg overlies the Oswayo and is bounded at the top by a disconformity. The Cussewago contains Arenicolites, Isopodichnus, Phycodes, Planolites, and Skolithos in upper shoreface sandstones possibly related to deposition in deltaic or tidal channel systems.Regionally, the Riddlesburg Shale records a range of euryhaline environments in shallow-shelf, open-bay, and probable estuarine facies. The Riddlesburg Shale Member at Rowlesburg is comprised of dark-grey silty shales, siltstones, and hummocky cross-stratified sandstones. Trace fossils include Bergaueria, Bifungites, Fustiglyphus?, Helminthopsis, Planolites, and Skolithos. Lithofacies of the Riddlesburg Shale in West Virginia were markedly influenced by a syndepositionally active basement feature, the West Virginia Dome. Riddlesburg-age shoreface sandstones deposited on the crest of the Dome contain apparent omission surfaces with common Rhizocorallium and Arenicolites, Cruziana?, Planolites, and Skolithos.

1985 ◽  
Vol 22 (9) ◽  
pp. 1274-1285 ◽  
Author(s):  
James H. Trexler Jr.

The Cretaceous Methow Basin of north-central Washington is the southernmost of a series of Mesozoic successor basins in the Cordillera of western North America. The Albian–Campanian(?) Virginian Ridge Formation comprises three members, newly defined here, that gradationally interfinger with each other and grade laterally and upward into overlying strata. Detailed stratigraphic analysts of the Virginian Ridge Formation and of the intimately related parts of the Winthrop and Midnight Peak formations indicates that these units represent complexly interfingering facies derived from a variety of sources, both to the west and to the east of the basin and locally within the system. This study suggests a detailed model for the history of the Upper Cretaceous Methow Basin: generation of a restricted basin with a stable, roughly north–south-trending axis, filled by a stable, east-derived fluvial and deltaic system (Winthrop Formation) interfingering with a laterally amalgamated, west-derived northward and eastward transgressive fan-delta system (Virginian Ridge Formation). The sequence grades upward into, and finally is overwhelmed by, locally derived volcanics of the Midnight Peak Formation. Similar, and in part coeval, successor basin sequences throughout the North American Cordillera may have been generated in response to similar tectonic settings.


Geologos ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 29-53 ◽  
Author(s):  
Alina Chrząstek ◽  
Monika Wypych

AbstractThe Coniacian quartz sandstones (Żerkowice Member, Rakowice Wielkie Formation) that crop out at quarries near Czaple-Nowa Wieś Grodziska (North Sudetic Synclinorium) contain a low-diversity assemblage of trace fossils:Gyrochorteisp.,Ophiomorpha nodosaLundgren, 1891,Ophiomorphaisp.,Phycodescf.curvipalmatum(Pollard, 1981), ?Phycodesisp.,Planolitescf.beverleyensis(Billings, 1862),Thalassinoides paradoxicusWoodward, 1830 and ?Thalassinoidesisp. Moreover, interesting compound burrow systems, here referred to asThalassinoides-Phycodescf.palmatusand ?Thalassinoides-Phycodes, were recognised at the Czaple Quarry. Additionally, ?Gyrochorteisp.,Phycodescf.flabellum(Miller and Dyer, 1878) and ?Treptichnusisp. were encountered at correlative levels in the Rakowice Małe Quarry. Some of these ichnotaxa have not been recorded previously from Coniacian sandstones of the Żerkowice Member. Additionally, in slabs of these sandstones, the gastropodNerinea bicinctaBronn, 1836 and the bivalveLima haidingeriZittel, 1866 were found. These interesting finds, in particular the gastropods, were already noted from the study area in the first half of the twentieth century by Scupin (1912–1913). Ethologically, the trace fossil assemblage is represented by domichnia or domichnia/fodinichnia (Ophiomorpha,Thalassinoides), fodinichnia (Phycodes) and pascichnia (Gyrochorte,Planolites). The compound burrow systems (Thalassinoides-Phycodes) are interpreted as dwelling/feeding structures. The possible tracemakers are crustaceans (Ophiomorpha,Thalassinoides) or worm-like animals (annelids and other) (Planolites, ?Phycodes,Gyrochorteand ?Treptichnus). The assemblage of trace fossils is characteristic of theSkolithosichnofacies andCruzianaichnofacies, typical of shallow-marine settings. Ichnological studies, as well as the presence of accompanying fossils (bivalves, gastropods), confirm the palaeoenvironmental reconstruction of the Żerkowice Member sandstones by Leszczyński (2010). That author interpreted the Coniacian sandstones as bar and storm deposits laid down in a shallow epicontinental sea (mainly the foreshore-upper shoreface; up to the middle shoreface) under normal oxygenation and salinity, in soft substrate, above fair-weather wave base. The deposition of the Żerkowice Member sandstones is linked to a regression that started after uplift of the southeastern part of the North Sudetic Synclinorium.


Quaternary ◽  
2021 ◽  
Vol 4 (4) ◽  
pp. 39
Author(s):  
Jean-Daniel Stanley ◽  
Tobias Ullmann ◽  
Eva Lange-Athinodorou

Geoarchaeological information presented here pertains to a subsidiary Nile channel that once flowed west of the main Sebennitic distributary and discharged its water and sediments at Egypt’s then north-central deltaic coast. Periodical paleoclimatic episodes during the later Middle and Upper Holocene included decreased rainfall and increased aridity that reduced the Nile’s flow levels and thus likely disrupted nautical transport and anthropogenic activity along this channel. Such changes in this deltaic sector, positioned adjacent to the Levantine Basin in the Eastern Mediterranean, can be attributed to climatic shifts triggered as far as the North Atlantic to the west, and African highland source areas of the Egyptian Nile to the south. Of special interest in a study core recovered along the channel are several sediment sequences without anthropogenic material that are interbedded between strata comprising numerous potsherds. The former are interpreted here as markers of increased regional aridity and reduced Nile flow which could have periodically disrupted the regional distribution of goods and nautical activities. Such times occurred ~5000 years B.P., ~4200–4000 years B.P., ~3200–2800 years B.P., ~2300–2200 years B.P., and more recently. Periods comparable to these are also identified by altered proportions of pollen, isotopic and compositional components in different radiocarbon-dated Holocene cores recovered elsewhere in the Nile delta, the Levantine region to the east and north of Egypt, and in the Faiyum depression south of the delta.


2005 ◽  
Vol 21 (6) ◽  
pp. 1856-1864 ◽  
Author(s):  
Jeanine Izabel Margraf Bittencourt ◽  
Rosely Magalhães de Oliveira ◽  
Ziadir Francisco Coutinho

The paracoccidioidomycosis mortality rate in the State of Paraná, Brazil (1980/1998) was analyzed using the death registry data from the Brazilian Mortality Information System and the estimated population from the Brazilian Institute of Geography and Statistics. To qualify the deaths, we deployed ICD-9 for 1980/1995 and ICD-10 for the more recent years. During this period there were 551 deaths from paracoccidioidomycosis in the State of Paraná. Most of the deaths were in male in the 30-59-year age group. The average annual mortality rate was 3.48 per million inhabitants, showing a tendency to stabilize during the study period. Paracoccidioidomycosis was the fifth cause of mortality among the predominantly chronic infectious diseases and had the highest mortality rate among the systemic mycoses. Paracoccidioidomycosis was observed in 184 counties in the State of Paraná. Most deaths were recorded in the North-Central meso-region, and the highest mortality rate occurred in the West meso-region.


PEDIATRICS ◽  
1961 ◽  
Vol 28 (1) ◽  
pp. 128-138
Author(s):  
Elizabeth R. Kramm ◽  
Marian M. Crane ◽  
Morton L. Brown ◽  
Monroe G. Sirken

Up to the present time accumulated experience with cystic fibrosis has been based on intensive study of relatively small groups of patients treated or seen for the disease in a few leading clinics in the country. This paper presents, for the first time, characteristics of patients with cystic fibrosis from a sample of hospitals throughout the continental United States. Estimates are based on sample data for 1957. The more important findings follow. Almost 70% of the estimated 2,500 patients with cystic fibrosis were discharged from hospitals in the Northeast and North Central regions of the United States. Only 9% of all cases were reported by hospitals in the West. Among hospitals approved for pediatric residency, discharges were more equally distributed between the four regions than among other types of hospitals. Almost half of the estimated 1,320 patients in non-pediatric residency hospitals were in the North Central region alone. Eighty-five per cent of hospitalized patients were under 10 years of age; approximately 30% were infants. About 5% were aged 20 years or more. In hospitals approved for pediatric residency, slightly over 1% of patients were aged 20 years or more, whereas, in other types of hospitals, 8% were were in the oldest age group. For every 100,000 children in the population under 21 years of age, about 4 were hospitalized for cystic fibrosis in 1957. Among children under 1 year of age, the rate for hospitalization due to cystic fibrosis was 18 per 100,000 live births in 1957; the rate was 8 per 100,000 in the child population under 5 years of age; for children 5 to 9 and 10 to 20 years, rates were about 3 and 1 respectively. There was a significant regional variation in rates for hospitalization because of cystic fibrosis. Whereas in both the Northeast and North Central regions there were about 5 patients under 21 years of age per 100,000 in the population under 21 years, there were only about 2 cases per 100,000 population in the same age group in both the South and West. For each of the four regions, the ratio of hospitalized cases of cystic fibrosis to child population was highest in the age group under 5 years. In the Northeast there were 11 children for every 100,000 in the population under 5 years of age hospitalized for cystic fibrosis; in the North Central region there were 10 children; in the South there were 5, and in the West, 4 children. Almost 15% of the 2,500 hospitalized patients with cystic fibrosis were discharged by death. Of the 360 patients with fatal cases, about 40% died during infancy; almost 25% died at ages 1 to 4 years; about the same proportion died at ages 5 to 9 years. The ratio of deaths from the disease per 100 cases hospitalized during the year was 18 for infants, 12 for children in the age group 1 to 4 years, 14 for children 5 to 9 years, and 12 for those aged 10 years or more. According to survey data, a larger number of males than females in each age group were hospitalized for cystic fibrosis. Among fatal cases under 10 years of age, however, the number of females slightly exceeded the number of males. More than one-third of the 2,500 patients had been previously discharged from the hospital reporting the case either in the same year or in some prior period. About 6% of all patients were discharged from the same hospital at least three times during 1957. Among the 360 patients discharged by death, over half were discharged two or more times during their lifetime from the hospital reporting the case. Among the 2,140 discharged alive, only about a third were reported to have multiple discharges from the same hospital.


1974 ◽  
Vol 28 ◽  
pp. 7-25
Author(s):  
James W. Mueller

The Paria Plateau survey was conducted on, and adjacent to, the Paria Plateau in Coconino County in north-central Arizona by personnel of the Museum of Northern Arizona during the summers of 1967 and 1968 (Fig. 1). All of the surveyed area is located in the Arizona Strip District of northern Arizona, although unsurveyed portions of the Paria Plateau extend into southern Utah. The Plateau is situated approximately midway between Page, Arizona on the east, and Kanab, Utah on the west. The familiar Vermillion Cliffs seen from U.S. 89 enroute to the North Rim of the Grand Canyon form the southern escarpment of the Plateau. The western boundary of the surveyed area is defined by Coyote and House Rock valleys which also separate the Kaibab and the Paria plateaus. The Paria River constitutes the northeastern boundary of the Paria Plateau making it a naturally bounded region within the Colorado Plateau subarea.


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