Iron River Research Articles

Development of duplex qPCR targeting Carnobacterium maltaromaticum and Vagococcus salmoninarum.

In November 2018, Vagococcus salmoninarum was identified as the causative agent of a chronic coldwater streptococcosis epizootic in broodstock brook trout (Salvelinus fontinalis) at the Iron River National Fish Hatchery in Wisconsin, USA. By February 2019, the epizootic spread to adjacent raceways containing broodstock lake trout (Salvelinus namaycush), whereby fish were found to be coinfected with Carnobacterium maltaromaticum and V.salmoninarum. To differentiate these two pathogens and determine the primary cause of the lake trout morbidity, a quantitative real-time PCR (qPCR) was developed targeting the C.maltaromaticum phenylalanyl-tRNA synthase alpha subunit (pheS) gene. The qPCR was combined with a V.salmoninarum qPCR, creating a duplex qPCR assay that simultaneously quantitates C.maltaromaticum and V.salmoninarum concentrations in individual lake trout tissues, and screens presumptive isolates from hatchery inspections and wild fish from national fish hatchery source waters throughout the Great Lakes basin. Vagococcus salmoninarum and C.maltaromaticum were co-detected in broodstock brook trout from two tribal hatcheries and C.maltaromaticum was present in wild fish in source waters of several national fish hatcheries. This study provides a powerful new tool to differentiate and diagnose two emerging Gram-positive bacterial pathogens.

Seismic geomorphology anomalies within a Pliocene deepwater channel complex in the Taranaki Basin, offshore New Zealand

The Taranaki Basin, located offshore New Zealand, is a Cretaceous rift basin that has well defined yet complex Miocene deepwater sedimentary systems. We analyze a pronounced anomalous seismic response in a Late Miocene to Early Pliocene deepwater channel within the 2005 Hector 3D survey located in the southern Taranaki Basin. Several seismic attributes were calculated to interpret the extent of these anomalous features. Analogues within both the Iron River reservoir in Albania, Canada and the East Breaks Basin Four, offshore Gulf of Mexico suggest that these anomalous seismic features are most likely channel-body basal scours. Another interpretation suggests that these scours were formed and later filled by mass transport deposits (MTDs) with sediment ponding as suggested from some studies within the Molasse Basin in southern Germany. Alternatively, these scours could also be interpreted as pockmarks resulting from channel abandonment and fluid escape due to compaction. Others describe this process within submarine canyon systems, offshore Equatorial Guinea. However, there is compelling evidence to suggest that these features are most likely channel-body basal scours rather than being related to MTDs or pockmarks. Within all of the interpretations, there is evidence of differential compaction, which is further supported by the reflectors displaying a slight doming immediately above where the scours are located. Geological feature: Seismic geomorphology anomalies within a Pliocene deepwater channel complex in the Taranaki Basin, offshore New Zealand Seismic appearance: Asymmetric bowl-shaped geometry with high-amplitude reflectors that are incised into underlying sediment Alternative interpretations: Pockmarks resulting from channel abandonment and fluid escape due to compaction Features with similar appearance: Channel scours or pockmarks Formation: Mount Messenger Formation, Taranaki Basin Age: Late Miocene to Early Pliocene Location: Southern Taranaki Basin, New Zealand Available data: Hector 3D data set, Kiwa-1, and Hector-1 wells Analysis tools: 3D seismic data, well logs, and seismic attributes

Vagococcus salmoninarum II-qPCR, tropism and egg-associated transmission.

Vagococcus salmoninarum was identified as the causative agent of a chronic epizootic in broodstock "coaster" brook trout (Salvelinus fontinalis) at the Iron River National Fish Hatchery. The epizootic spanned more than a year, was unresponsive to multiple florfenicol treatments, and resulted in >50% mortality of the affected fish. The decision was made to cull the remaining fish during spawning, which presented an opportunity to more thoroughly examine V. salmoninarum sampling methods, organ tropism and vertical transmission. A newly developed qPCR targeting the pheS gene was used in concert with bacterial culture to show that V. salmoninarum indeed disproportionately affects females and has a tropism for female reproductive tissues. The study demonstrates that some female reproductive tissues (e.g. ovarian fluid, unfertilized eggs) are also an effective option for non-lethal detection. Despite the widespread presence of V. salmoninarum in ovarian fluid and on egg surfaces, we found no evidence of intra-ova transmission.

Vagococcus salmoninarum I—A chronic coldwater streptococcosis in broodstock brook trout (Salvelinus fontinalis) in Wisconsin, USA

In 2018, Vagococcus salmoninarum was isolated from two lots of broodstock "coaster" brook trout (Salvelinus fontinalis) containing ~1,500 fish at the Iron River National Fish Hatchery, at which time it was identified as the causative agent of a chronic coldwater streptococcosis epizootic. Clinical signs included exophthalmia, lethargy, erratic swimming and loss of equilibrium. Female fish experienced disproportionately higher morbidity and mortality than male co-inhabitants, and routinely retained eggs following spawning. The most consistent gross clinical sign was heart pallor and turbid pericardial effusion. An attempted treatment using florfenicol was ineffective at halting the epizootic, which spanned more than a year and resulted in >50% mortality before remaining fish were culled. As there is no previous documentation of V. salmoninarum at this hatchery or in this species, it is still unclear what circumstances led to this epizootic. The inability to treat this chronic disease led to the loss of valuable broodstock, hampering ongoing fishery conservation efforts in the Great Lakes Basin.

Telehematology: Expanding Comprehensive Care for Pediatric Patients with Blood Disorders through Telemedicine at Several Delivery Sites (Medical Homes, Hospital Clinics, Home Setting and Hemophilia Treatment Centers (HTC)) and with Interdisciplinary Providers

Background: Telemedicine (TM) is the exchange of medical information from one site to another via electronic communications to improve patients' health status and access to care. We used telemedicine to provide comprehensive hematology services to patients with blood disorders at a variety of sites that included medical homes, hospital specialty clinics, HTC, patients home and teleconsultation with out of state HTC, all located at a distance from the Michigan State University Center for Bleeding and Clotting Disorders (MSU CBCD). The goals were to increase access to family centered and culturally competent specialty care and increase the numbers of patients with blood/bleeding/clotting disorder that were timely and accurately diagnosed, managed and referred for specialty care.Objectives: 1) To understand the feasibility of telemedicine between specialists and a variety of remote sites for children with bleeding/blood disorders 2) To assess the acceptability by patients, families, primary care physicians, remote site staff, specialist physicians, and specialist staff and 3) To assess the cost of telemedicine visits versus traditional visits from the societal perspective 4) To provide education and resources to distant providers.Methods: Telemedicine sites were 1) two medical homes-one at a pediatrician's office, Upper Great Lakes Family Health Center (UGLFHC)/Portage Health in Houghton MI and the other at a family medicine office, Iron Mountain/Iron River Upper Peninsula, MI 2) specialty clinics at Marquette General Hospital, Marquette MI 3) Hemophilia Treatment Centers (HTC) at Traverse City MI and Rush University IL 4) and a patient's home in MI. PolycomTM and/or VidyoTM systems were used to deliver HIPAA (Health Insurance Portability and Accountability Act) regulated bidirectional videoconferencing technology. Records of patient visits seen by local providers and via TM by MSU CBCD pediatric hematologists, nurse and social worker were obtained. Data included patient diagnosis, distance traveled, estimated time and travel costs saved, and education of distance provider. Measurable objectives included feasibility, acceptability. Technology issues were addressed. Site visits with Portage and Iron River Health Department were conducted to discuss local barriers and needs.Results: Beginning 1998, a total of 68 patients, ages 2 weeks to 17 years and their families were seen by TM at various sites. There were 97 TM visits and frequency of clinics varied monthly to as needed. Average distance travelled by patients to local clinics ranged from 12 - 70 miles (range 2-170 miles). In addition to coagulation disorders (hemophilia, von Willebrands disease, factor deficiencies, patients with bleeding symptoms such as epistaxis, menorrhagia etc.), other diagnosis such as cytopenias, spherocytosis, hemoglobinopathies, lymphadenopathy, Hereditary Hemorrhagic Telangiectasia, Ehlers Danlos Syndrome, and pediatric oncology patients in follow-up phase were also seen and in some cases family members tested. Physician and staff were educated regarding disease management; guidelines and educational materials shared. Estimated costs per patients to fly or drive to MSUCBCD were $999 ($579 -$1275) and $1653 ($1405-1887) respectively compared to obtaining care locally $87.6 ($73-117) via TM. This resulted in cost savings per patient of $911.4 and $1565.7 for driving and flying respectively. The MSU CBCD team also incurred significant cost savings by avoiding travel/lodging costs. Interviews with staff and physicians resulted in improvement in TM acceptance and delivery. A majority of laboratory testing were send-outs and local testing for platelet function defects were not available. Technology issues addressed included adjustments in bandwidth, firewall and network settings. It was feasible to do consultations with out-of-state HTCs as well as follow patients at home.Conclusion: Besides improving access to specialty care, TM with remote areas is feasible and acceptable in a variety of settings with considerable time and cost savings for both patients as well as the specialty care treatment team. Our study is in accordance with the American Academy of Pediatrics recent policy statement (Pediatrics 2015;136:202-209) recommending that TM services be coordinated through the medical homes thereby involving local primary care providers. DisclosuresKulkarni:Biogen: Research Funding, Speakers Bureau; Baxter: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Pfizer: Membership on an entity's Board of Directors or advisory committees; Kedrion: Membership on an entity's Board of Directors or advisory committees; BPL: Membership on an entity's Board of Directors or advisory committees. Witkop:Pfizer: Other: Advisory Board, Research Funding; Baxter Bioscience: Other: Advisory Board; Novo Nordisk: Other: Advisory Board, Speakers Bureau.

Genetic and morphological divergence in three strains of brook trout Salvelinus fontinalis commonly stocked in Lake Superior.

Fitness related traits often show spatial variation across populations of widely distributed species. Comparisons of genetic variation among populations in putatively neutral DNA markers and in phenotypic traits susceptible to selection (QST FST analysis) can be used to determine to what degree differentiation among populations can be attributed to selection or genetic drift. Traditionally, QST FST analyses require a large number of populations to achieve sufficient statistical power; however, new methods have been developed that allow QST FST comparisons to be conducted on as few as two populations if their pedigrees are informative. This study compared genetic and morphological divergence in three strains of brook trout Salvelinus fontinalis that were historically or currently used for stocking in the Lake Superior Basin. Herein we examined if morphological divergence among populations showed temporal variation, and if divergence could be attributed to selection or was indistinguishable from genetic drift. Multivariate QST FST analysis showed evidence for divergent selection between populations. Univariate analyses suggests that the pattern observed in the multivariate analyses was largely driven by divergent selection for length and weight, and moreover by divergence between the Assinica strain and each of the Iron River and Siskiwit strains rather than divergent selection between each population pair. While it could not be determined if divergence was due to natural selection or inadvertent artificial selection in hatcheries, selected differences were consistent with patterns of domestication commonly found in salmonids.

How Not to Arm a State

Today’s “Iron River of Guns” flowing from the United States into Mexico has a long backstory. From Mexico’s independence movement in the early nineteenth century through its early twentieth-century revolution, the international arms trade in general and arms transfers from the U.S. in particular have often confounded the project of national governance. The vagaries of global arms markets, the dangers of arming the state on credit, the difficulties of maintaining government arsenals, and the misfortune of sharing land borders with major arms producers all shaped Mexico’s first independent century in surprising and neglected ways. This history offers a fresh perspective on the contemporary crisis and the policy debate surrounding it.

Channel-body basal scours: Observations from 3D seismic and importance for subsurface reservoir connectivity

Scouring at the base of channel bodies plays a significant role in enhancing connectivity of sandstone reservoirs. Investigation of high-resolution 3D seismic data from a fluvial and deep-water channel system illuminates the location and spacing of channel-body basal scours and possible controls. Scours in both East Breaks upper fan (Quaternary) and Iron River fluvial channel-bodies (Cretaceous) are comparable in scale, with a deviation of up to 10 m scour depth relative to the average channel-body basal depth.Substrate lithology, as documented by draping well-calibrated seismic response onto 3D channel body basal surfaces, does not appear to be a major influence on scour location or depth. In the datasets examined, channel-body basal scour locations appear to be most influenced by changes in channel orientation, with outer bends being particularly prone to scouring, even in channels that are not highly sinuous.Scaling relationships between scour spacing and channel width observed in modern fluvial systems are further tested against these high-resolution datasets and published Miocene subsurface deep-water reservoir maps but results are mixed, with a consistent over-prediction of scour spacing. This may reflect difficulties in accurately determining channel bank full width in confined deep-water channel complex systems.Observations from an ancillary 4D seismic dataset show that over 30% of the identified scour areas exhibit attribute anomalies calibrated with water saturation changes between the baseline and monitor surveys (about 3 years) and thus indicate production-induced fluid movement through these features. This underlines the importance of scours as connection points between fluid compartments and the significance of observations of scour location and spacing made here from high-resolution 3D and ancillary 4D seismic data.

Cost ramifications of municipal consolidation: A comparative analysis

In 2001, the first municipal consolidation occurred in over 100 years in Michigan between two cities and one village in Michigan's rural Upper Peninsula, forming the City of Iron River. The three units of government combined to have a population of 3,391 within the newly incorporated boundaries. Driving the consolidation was continual population loss and erosion of the economic tax base of the individual municipal governments since the 1960s. This study sought to assess whether, five years after the consolidation, the governments had saved money as compared to a peer group of governments in Michigan. The findings indicate that the new city of Iron River was able to provide some evidence of cost control and savings following the consolidation.

From Bars to Valleys: The Sedimentology and Seismic Geomorphology of Fluvial to Estuarine Incised-Valley Fills of the Grand Rapids Formation (Lower Cretaceous), Iron River Field, Alberta, Canada

Abstract A high-resolution 3D seismic data set from Alberta, Canada, has revealed great detail in the morphology and architecture of a series of incised-valley fills from the Grand Rapids Formation (Albian, Lower Cretaceous). A large-scale well-log study was used to place the seismic stratigraphic architecture in regional context. Seismic facies were calibrated with numerous cores and wells. The data reveal that the Grand Rapids Formation was composed of shoreface parasequences cut by many incisions filled with fluvial to estuarine facies. The incisions contain one to several channel fills with a range of bar architectures, but dominated by lateral accretion. Incised valleys are here defined as any fluvial incision that is bounded below by a sequence boundary. Incised valleys form in response to a relative fall in sea level and, unlike distributary channels, are not in facies relationship with the surrounding sediments into which they are incised. A range of direct and indirect evidence indicates that all of the studied incisions into the shoreface parasequences are incised valleys. Thirty-two incised valleys were identified in the Grand Rapids Formation in the 3D seismic. They range in width from a few tens of meters to a few kilometers, and in depth from 5 to 60 m. There is no relationship between the size of a valley and its stratigraphic position. Composite sequence boundaries have many, intersecting incised valleys of a range of size. High-frequency sequence boundaries have only a few incised valleys. None of the incised valleys have a dendritic drainage network; they mostly have straight to gently sinuous edges. They were interpreted to have formed from fluvial entrenchment rather than knickpoint migration. Valleys also exhibit large variations in depth of the thalweg over short distances. This is interpreted to result from local processes based on the application of an engineering model that predicts scour depth of modern channels.

William C. Mitchell

William C. Mitchell died January 2, 2006, at his home in Eugene, Oregon. He had suffered from pulmonary fibrosis. He was 80. His wife since 1959, Joyce Mitchell, died in 1996; he is survived by a brother James W. Mitchell, of Kingsford, Michigan, and two sisters, Jeanine Watt of Iron River, Michigan and Waverly Jarvis of Withee, Wisconsin.

Interpersonal violence at Lepenski Vir Mesolithic/Neolithic complex of the Iron Gates Gorge (Serbia‐Romania)

The Mesolithic populations of the Danube River's Iron Gates Gorge (Serbia/Romania) spanned over 1,500 years (from before 7000 bc to around 5500 bc) in one of the most favorable foraging environments of Europe. Over most of these 1,500 years, the dominant economy was foraging, but farming was practiced by communities in the region from around 6500 bc. This research examines individuals from four sites on the Danube (Lepenski Vir, Vlasac, Padina, and Hajducka Vodenica) whose traumatic lesions can be most plausibly interpreted as resulting from violent interactions. Given over four hundred individuals buried at these sites (MNI = 418), the episodes of violent interactions were few and without evidence of a specific temporal pattern. They probably represent sporadic episodes of interpersonal conflict that do not support the notion of endemic warfare deemed typical of the Mesolithic, or elevated levels of interpersonal/intertribal conflict at the time of contact with farming communities. The difference in patterns of violence between the Mesolithic sites on the right bank of the Danube and a coeval site of Schela Cladovei on the left bank is explained in terms of differences in archaeological context, geographic location, and possibly specific local histories.

Hatchery Performance Attributes of Nipigon, Assinica, and Iron River Strains of Age-0 Brook Trout

The fingerling hatchery performance attributes of brook trout Salvelinus fontinalis of Lake Nipigon origin were compared with those of domesticated (Assinica) and nondomesticated (Iron River) strains of this species in a 150-d laboratory experiment. Despite similar initial sizes, the final mean length and weight of the Assinica strain (134.9 mm and 26.3 g) were significantly greater than those of the Nipigon (112.6 mm and 13.6 g) and Iron River (111.2 mm and 14.6 g) strains. Specific growth rates differed significantly among strains, with Assinica fish having the greatest mean daily percent increases in length and weight (0.98% and 3.10%, respectively), followed by the Iron River (0.93% and 3.03%) and Nipigon (0.86% and 2.69%) strains. The mean daily absolute rates of growth in length and weight were similar in the Nipigon and Iron River strains but significantly lower than for the Assinica strain. Survival rates and food conversion efficiency estimates were not significantly different among the three strains of brook trout. Relative weight values were significantly greater for Assinica (96.4%) and Iron River (94.0%) fish than for Nipigon (87.0%) fish. Based on these results, we recommend that fingerling Nipigon brook trout be reared more like nondomesticated strains of this species, such as Iron River fish, in hatchery environments.

Seasonal Changes in Ruffe Abundance in Two Lake Superior Tributaries: Implications for Control

Abstract Since the discovery of ruffe Gymnocephalus cernuus in the St. Louis River in 1987, state, federal, and tribal management agencies have sought to slow its spread to areas outside the western end of Lake Superior. A debate over control strategies highlighted uncertainties about seasonal movements of this species between Lake Superior and its western tributaries. One strategy called for eliminating reproducing populations in tributaries on the periphery of the range using chemical piscicides. That strategy rested on the assumption that ruffe congregate in tributaries during a predictable time of year. This study was designed to explore that assumption. Ruffe collections from the Iron and Sand rivers during 1995 indicated that ruffe were present in those tributaries throughout the summer but that abundance was not highest at the predicted time: June 19–22. Maximum abundance in the Iron River did not coincide with that in the Sand River and did not occur during June 19–22 in either river. The timing o...

Illite/Smectite Geothermometry of the Proterozoic Oronto Group, Midcontinent Rift System

AbstractCharacterization of the Nonesuch Formation, middle unit of the Proterozoic Oronto Group, as a potential hydrocarbon source for the Lake Superior basin portion of the Midcontinent Rift system requires an understanding of the thermal maturity of the region and its relationship to the thermal history. Illite/smectite (I/S) expandability data were collected from the Nonesuch Formation and the overlying Freda Sandstone and compared with organic thermal maturity data; both data sets coupled with a thermal and burial history for the White Pine area of Michigan allow regional interpretation of maximum formation temperatures of the Nonesuch Formation and the Freda Sandstone with respect to time. Samples collected from drill holes in northeastern Wisconsin display nearly pure smectite within the lower Freda Sandstone trending abruptly to ordered I/S within the Nonesuch Formation. Regular trends of decreasing expandability with depth occur in four other drill holes to the northeast. Comparison of I/S expandability between similar stratigraphic intervals reveals a significant trend of increasing thermal maturity to the northeast, with the lowest thermal maturities observed in the Iron River Syncline area just west of White Pine, Michigan.I/S geothermometry suggests maximum temperatures in the Nonesuch Formation of 140°C in Wisconsin, 115°C in the Iron River Syncline area, 160°C at White Pine, and 190°C near the southern portions of the Keweenaw Copper District. The geographic pattern of temperatures determined from I/S geothermometry is identical to that determined from organic thermal maturity indicators in the Nonesuch Formation (Imbus et al., 1988, 1990; Hieshima and Pratt, 1991; Pratt et al, 1991; Mauk and Hieshima, 1992).Regular variations in I/S expandability with depth occur in the Freda Sandstone and the Nonesuch Formation near the southern limits of the Keweenaw Copper District. These variations suggest a fossil geothermal gradient of 55°C/km and limit the thickness of sediment above the Nonesuch Formation to approximately 3 km. In comparison, 3.6 km of Freda Sandstone are presently exposed near the Wisconsin border, and numerical modeling suggests a range of 4–6 km of sediment overlying the Nonesuch Formation. None of the data indicate the presence of the Bayfield Group sediments above the Nonesuch Formation at the time of clay diagenesis. Samples from White Pine suggest a two-stage burial history: 1) clay reaction, possible hydrocarbon maturation, and copper-sulfide mineralization at maximum temperatures above 100°C during the main rifting and burial event, followed by 2) fracturing, reverse faulting, and fluid circulation during a rift-terminating compressional event that may have allowed petroleum migration and native copper mineralization at temperatures below 100°C. Abrupt changes in I/S expandability with depth and the presence of poorly crystalline I/S (greater than 80% expandable) and kaolinite in the Freda Sandstone in Wisconsin appear to represent later overprinting of the diagenetic assemblage by fluids that were probably cooler and of differing composition than earlier diagenetic fluids. However, the authigenic assemblage from the vicinity of White Pine, Michigan, which includes up to 25% expandable I/S, appears to represent a diagenetic profile formed during the main rifting and burial event. Therefore, these expandable I/S-type clays are essentially 1.0 billion years old.

Precambrian vein pyrobitumen: evidence for petroleum generation and migration 2 Ga ago

Abstract Isotopic, optical reflectance, and chemical analyses of large pure samples of Lower Proterozoic vein pyrobitumens (anthraxolite and thucholite of older reports) collected from five widely separated localities in the Great Lakes region of the United States and Canada suggest that in the Lower Proterozoic oil was generated from kerogen and migrated in much the same way as during the Phanerozoic. Furthermore, maturation and organic metamorphism followed the same successive stages that mark the generation and destruction of Phanerozoic petroleum. Kerogens derived from algae and bacteria were deposited with subaqueous muds that ultimately became black shales or slates. Some of the kerogen, however, yielded petroleum, which migrated into fractures and subsequently became pyrobitumen. The δ13C values average −32.6%. (PDB). This value compares favorably with those from Phanerozoic petroleum and asphaltites and is consistent with the proposition that the carbon isotopes were fractionated by biological activity. Reflectance values of the pyrobitumens range from 0.9% for Elliot Lake, Ontario, to 9.5% for Iron River, Michigan, and H/C ratios range from 0.6 for Elliot Lake to 0.1 for Sudbury, Ontario. When compared with the stages of petroleum maturation, these values indicate maturation which ranges from the catagenesis stage through the metagenesis stage of petroleum generation and metamorphism.

Clonal variation in the incidence of Hypoxylon canker on trembling aspen

The incidence of Hypoxylon canker, caused by Hypoxylon mammatum (Whal.) Miller, on ramets of 80 pole-sized Populus iremuloides clones was determined on three sites near Pellston, Michigan, and two sites near Iron River, Michigan. Variation in the incidence of canker within clones was slight. No significant difference (P >.05) in canker incidence was found among NE, SE, SW, and NW quadrants of 47 clones on the Pellston Plain site. Significant differences (P <.005) were found among clones in the incidence of canker in four of the five sites studied. In some cases, nearby or adjacent pairs of clones showed significant and striking differences in the incidence of canker infection. The range in canker incidence (percentage of living and dead ramets with stem or branch cankers) for all clones was 9 to 90%; the range was wide on all sites. Low stand density and light bark color of ramets were both significantly (P <.01 and P <.05, respectively) correlated with high canker infection.Although genetic differences between clones in the incidence of canker were not proven, the marked phenotypic differences among clones and other findings suggested moderate genetic control on four of the five sites investigated. In studies relating the incidence of canker to site and biotic factors, the clonal structure of aspen stands should be recognized, and the clone should be used as the basic unit of sampling.

STRUCTURE, STRATIGRAPHY, AND PALEONTOLOGY OF AN UPPER TRIASSIC SECTION ON THE WEST COAST OF BRITISH COLUMBIA

The highly deformed section at Open Bay is one of the few good exposures of a thick sedimentary unit within the prebatholithic rocks along coastal British Columbia. It provides new structural information relating to emplacement of a part of the Coast Range batholith and it contains an important Upper Triassic fauna unusually well represented. Structural and paleontological analyses are mutually supporting and are purposely combined in one paper.Thirteen ammonite genera from 14 localities clearly substantiate McLearn's tentative assignment to the Tropites subbullatus zone (Upper Karnian) and suggest a restriction to the T. dilleri subzone as defined in northern California.Contrary to an earlier view, the beds are lithologically similar across the whole bay except for variations in the intensity of deformation and thermal alteration. Their contact with slightly older relatively undeformed flows is apparently a zone of dislocation. Stratigraphic thicknesses cannot be measured with confidence, and subdivision into "Marble Bay Formation" and "Open Bay Group" cannot be accepted. Open Bay Formation is redefined to include all the folded marble and interbedded pillow lava at Open Bay. Lithologic and biostratigraphic correlation is suggested with the lower middle part of the Quatsino Formation on Iron River, 24 miles to the southwest. Basalt flows and pillowed volcanics west of Open Bay are correlated with the Texada Formation within the Karmutsen Group.The predominant folding is shown to precede, accompany, and follow intrusion of numerous andesitic pods and to precede emplacement of quartz diorite of the batholith. Structural asymmetry is shown to have originated through gentle cross-folding and emplacement of minor intrusives during deformation.

Clay minerals associated with the Lake Superior iron ores

Accessory clay-size minerals occur as disseminated particles and as fillings of pockets and fissures in the Lake Superior iron ores, the oxidized iron-formation, and the associated altered dikes. Dickite and kaolinite are the most abundant clay minerals in the Marquette, Gogebic, and Iron River districts of Michigan and are accompanied by lesser amounts of nacrite, talc, pyrophyllite, 1M and 2M 1 muscovite, lizardite, clinochrysotile, Al-serpentine, dioctahedral and trioctahedral chlorite, dioctahedral and trioctahedral montmorillomte, palygorskite, and regular interstratifications of chlorite-montmorillonite, as well as the non-clay minerals apatite, alunite, gypsum, calcite, and rhodochrosite. This assemblage is suggestive of a hydrothermal environment. In contrast only kaolinite, 1M muscovite, chlorite, nontronite, montmorillonite, talc, chamosite, apatite, gibbsite, and alunite have been identified from the Mesabi, Cuyuna, and Vermilion districts of Minnesota. The distinctive differences in the assemblages of minerals and in the types of kaolin minerals present in the Michigan and Minnesota areas are believed to be indicative of differences in the environment of formation of the clay-size components in the two areas. The intimate association of the clays with the iron ore suggests that these differences may also extend to the origin of the ore itself.

ANTHRACITIC COAL FROM PRECAMBRIAN UPPER HURONIAN BLACK SHALE OF THE IRON RIVER DISTRICT, NORTHERN MICHIGAN

Research Article| October 01, 1957 ANTHRACITIC COAL FROM PRECAMBRIAN UPPER HURONIAN BLACK SHALE OF THE IRON RIVER DISTRICT, NORTHERN MICHIGAN S. A TYLER; S. A TYLER DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN Search for other works by this author on: GSW Google Scholar E. S BARGHOORN; E. S BARGHOORN DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN Search for other works by this author on: GSW Google Scholar L. P BARRETT L. P BARRETT DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN Search for other works by this author on: GSW Google Scholar Author and Article Information S. A TYLER DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN E. S BARGHOORN DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN L. P BARRETT DEPARTMENT OF GEOLOGY, UNIVERSITY OF WISCONSIN, MADISON, WISCONSIN; BOTANICAL MUSEUM AND BIOLOGICAL LABORATORIES, HARVARD UNIVERSITY, CAMBRIDGE, MASS.; BOX 119, ISPEMING MICHIGAN Publisher: Geological Society of America Received: 02 Feb 1957 First Online: 02 Mar 2017 Online Issn: 1943-2674 Print Issn: 0016-7606 Copyright © 1957, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S. government employees within the scope of their employment. GSA Bulletin (1957) 68 (10): 1293–1304. https://doi.org/10.1130/0016-7606(1957)68[1293:ACFPUH]2.0.CO;2 Article history Received: 02 Feb 1957 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation S. A TYLER, E. S BARGHOORN, L. P BARRETT; ANTHRACITIC COAL FROM PRECAMBRIAN UPPER HURONIAN BLACK SHALE OF THE IRON RIVER DISTRICT, NORTHERN MICHIGAN. GSA Bulletin 1957;; 68 (10): 1293–1304. doi: https://doi.org/10.1130/0016-7606(1957)68[1293:ACFPUH]2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract An anthracitic carbonaceous sedimentary rock interbedded in the upper Huronian, Michigamme shales of the Iron River District, Michigan, has been subjected to intensive petrographic and chemical analysis as well as x-ray diffraction study. Field studies were aided by small-scale stripping and trenching operations. The coal occurs as lenticular bodies concordantly bedded with the Michigamme black shale. Similar relations between anthracitic coal and black shale have been observed in drill cores taken at a depth of 1000 feet several miles distant. The associated black shales exhibit numerous graphitic elliptical bodies of varying size but relatively constant form. These are interpreted as being of organic origin. Numerous small elliptical structures may also be observed in flame-etched polished surfaces of the anthracitic coal. X-ray diffraction patterns demonstrate that the coally sedimentary rock is partially graphitized, but less so than that of Rhode Island meta-anthracite of Pennsylvanian age. Use of various extractive and chromatographic techniques demonstrates the presence of strongly pigmented organic compounds. The organic extractives show strong fluroescence in ultraviolet light, solubility in both acid and base solutions, color change with pH change, relatively featureless absorption spectra in the visible and ultraviolet light, and high thermal stability. Oxidative treatment increases the yield of organic extractives. Concatenation of the evidence on the origin and composition of the Michigamme anthracitic carbon suggests probable derivation from algal remains. The sedimentary rock is, hence, of much interest in connection with the problem of the antiquity of Precambrian life. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.