Pyritic shale

Oct 1, 2019 · The wide distribution of δ 34 S values from the jarosite samples, which are consistently heavier than the corresponding pyritic shale values, indicates a partial sulphate input from isotopically heavier sources, potentially modern seawater or artificial fertilisers (Fig. 9). Download : Download high-res image (300KB)

Pyritic shale. In Green River oil shale, sulfur occurs in both inorganic and organic combinations; 70 to 85% of the sulfur is present as pyrite, and most of the remaining …

The giant stratiform Zn–Pb–Ag HYC deposit displays a broad Zn, Pb and Tl halo which extends laterally along the favourable pyritic black shale facies of the Barney Creek Formation for at least 15 km west of the deposit. A ferroan dolomite/ankerite

@article{osti_433572, title = {The development of an inhibited explosive for black pyritic reactive shale}, author = {Bellairs, P}, abstractNote = {The Hamersley Province is located 1,000km to the North of Perth the Capital City of Western Australia and is of major economic significance due to mining. A small but significant proportion of the ...Mudstone is vertically and laterally heterogeneous in terms of variations in mineral composition, organic carbon content, and petrophysical properties. The purpose of this study is to classify mudstone lithofacies within the High Radioactive Zone (HRZ) Shale on the North Slope, Alaska, based upon mineralogy, total organic carbon (TOC), and petrophysical properties to …pyritic shale is based on the application of state-of-the-art conceptual and numerically modeling tools, and operational considerations. The potentially acid forming material is encapsulated within barren run -of-mine material. A moisture storage and release cover system is employed to control water infiltration on the sloping and horizontalExpansion of Pyritic Shales. CBD-152. Expansion of Pyritic Shales. Originally published 1972. Weathering of rock formations containing pyrite--an oxidation process--results in a volume increase associated only recently with basement floor heave in Canada. It is now known that pyrite weathering was identified as early as 1950 as a major ... Oil shale is just one unconventional oil source that's being researched. Learn how oil shale could save the day when — and if — we hit peak oil in the U.S. Advertisement Pe­ople who owe money have a way of turning the table on their credito...High-resolution Hg chemostratigraphy (Figs. 1 and 2) reveals two distinct excursions in Hg concentrations in regions dominated by organic-rich, pyritic black shale, with maxima of 491 ng/g at 179.05 m and 1,593 ng/g at 141.47-m stratigraphic depth. We examined these two intervals from 190 to 168 m and from 153 to 125 m at high stratigraphic ... Jul 7, 2023 · The age of the Bedford Shale and the Berea Sandstone is changed from Late Devonian and Early Mississippian to Late Devonian only (late Famennian) in the Michigan and Appalachian Basins because of the realignment of the Devonian-Mississippian boundary in the United States with the accepted Devonian-Carboniferous boundary in Europe.

Vertical surfaces of shale exposed in trenches, disturbance by blasting, or fault zones that allow air penetration horizontally tend to enhance the rate of weathering and lead to very severe conditions. Fills of pyritic materials are particularly subject to accelerated weathering and heaving.The chemical nature of the weathering of pyritic shale is complex and the rate of pyrite oxidation is a function of the mineralogical properties of the pyritic shale, chemical, physical and biological factors such as particle size, temperature of the environment, microbiological activity, oxygen concentration in the gas and water phases (Ritcey ...The Francis Creek Shale Member containing the Mazon Creek Lagerstätte was deposited on the NE margin of the Illinois Basin, ... Between the concretion zone and this ‘normal’ non-concretionary deposit, the Francis Creek Shale Member contains pyritic/calcite concretions almost completely devoid of any fossils, ...29 ມິ.ຖ. 2022 ... Irradiation of the pyritic shale in ferrous iron solutions (0.2 mM) produced sulfate at a rate of 4.2 × 10−9 ± 0.2 × 10−9 mol/m2 per second ( ...The Marcellus Shale is the most extensive of a series of Appalachian black-shale formations deposited in sediment-starved subsiding foreland basins during the Devonian Period. The targeted black shales in the Marcellus, which are delineated on geophysical logs by their elevated gamma radiation and low density, are organic rich and pyritic.Se was found in a weathered pyritic shale, using synchrotron µ-X-ray fluorescence (XRF), X-ray absorption fine structure (XAFS) and XANES, to be present predominantly as Se(IV) with Se(VI) also ...20 ກ.ຍ. 1990 ... PYRITIC WTZITE. RUSTY PYRITIC WARTZITE. RUSTY TRIICHYTE? HEMTITIC SILTSTONE. RUSTY SHALE. RUSTY SHALE. RUSTY SHALE. RUSTY SILSTONE. PYRITIC ...Jan 5, 2023 · Shale. Shale is the most abundant of all sedimentary rocks. It is composed primarily of soft clay minerals, but may include variable amounts of organic matter, calcareous material, and quartz grains. Shale may be any color, but is generally greenish gray to grayish black. It is relatively soft and has a smooth, greasy feel when freshly exposed ...

Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden. Expansion occurs ...Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden. Expansion occurs ...Antrim Shale - Black shale; gray shale and limestone in lower part · Ellsworth ... pyritic shale. Contains one or more thin-bedded limestones, including the ...Synsedimentary to Diagenetic Cu±Co Mineralization in Mesoproterozoic Pyritic Shale Driven by Magmatic-Hydrothermal Activity on the Edge of the Great Falls Tectonic Zone–Black Butte, Helena ...This Rock-Eval 6S method for pyritic and organic sulphur quantification was applied on sets of organic rich sedimentary rock samples from the Grey Shale Member in North Yorkshire and from the ...the pyritic shale and calcareous limestone beds. Also, both the carbonate and sulfuric components need to interact in an aqueous environment, inferring that the dissolution of the carbonate from the calcium carbonate found within the limestone beds is occurring (Martin, 2008). The Mapleton Quarry, located in Huntingdon

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A PYRITIC SHALE FORMATION IS EXPOSED AT A QUARRY FACE. WITHIN THREE YEARS OF EXPOSURE, OXIDATION OF THE PYRITE HAS LED TO IRON OXIDE STAINING AND DEGRADATION OF THE SURROUNDING SHALE. FIGURE 2. A RELATIVELY THICK BEDDING PLANE CONTAINED IN A SHALE FRAGMENT IS PICTURED.The term New Albany has been used in the literature since that time. Description: The New Albany Shale is composed of brownish-black carbon-rich shale, greenish-gray shale, and minor amounts of dolomite and dolomitic quartz sandstone (Lineback, 1968, 1970). As recognized by Lineback, the formation consists of five members in southeastern Indiana. Pyrite is a pretty mineral (Fig. 1) common to Indiana, but it also has a dark side. It is composed of iron (Fe) and Sulfur (S) with a chemical formula of FeS2. Atoms are arranged in an isometric crystal structure (Fig. 2) that makes cubic crystals. It shows a brassy, bright metallic luster when fresh, but readily tarnishes to dull surfaces upon exposure (Fig. 3A).Cretaceous pyritic roof shale from Onyeama mine in Enugu colliery was studied for the geotechnical and compositional characteristics relevant to its use in civil engineering construction and other industries. Properties investigated included moisture absorption, particle size distribution, plasticity, linear shrinkage, compaction, California bearing ratio …

Mudstone lithofacies in the HRZ Shale, such as pyritic organic mudstone, pyritic organic siliceous shale, pyritic grey mudstone, and grey mudstone, can be correlated for up to 90 miles (∼145 km). The aforementioned facies are present within all wells.Vertical surfaces of shale exposed in trenches, disturbance by blasting, or fault zones that allow air penetration horizontally tend to enhance the rate of weathering and lead to very …non-pyritic shale with thin-bedded dolomite a nd rare chert bands that is very strongly . invaded by secondary calcite with vughs containing fibrous gypsum. The BIF in .Shale producers will keep oil prices low for at least another two years. OPEC is once again at odds with the market. This time, it’s not about the cartel’s strategy to dominate the oil trade. Instead, OPEC is in a debate with industry analy...Structural damage to buildings and other civil infrastructure by expansive pyritic shale is becoming increasingly prevalent as construction continues to expand into undeveloped areas as engineering knowledge of the damaging effects of building on or with this material remains inadequate. Establishing a database of case studies regarding ...the distruptive potential of pyritic shale fill (continued) figure 6. a one inch-wide crack with a three-quarter-inch vertical offset was . documented in a concrete floor slab over . pyritic shale fill. portions of the slab had . heaved upward more than two inches over three years before the slab and underlying fill were removed.swelling of the underlying pyritic shale are not yet established. This paper investigated both the swelling behavior of a pyritic shale obtained from the project site under various …6 ທ.ວ. 2016 ... ... shales, marine shales, siltstones, sandstones, coals, marine limestones, and chert ("flint"). The lower Pottsville dates to the late Early ...Expansion of Pyritic Shales. Originally published 1972. E. Penner, W.J. Eden, P.E. Grattan-Bellew. Weathering of rock formations containing pyrite--an oxidation process--results in a volume increase associated only recently with basement floor heave in Canada.Pyrite is essentially the only sulfide mineral in these shales. Pyritic shale horizons occur along the basin margins, and it is feasible that colloidal iron was …The Upper Permian Linghao Formation shale is the most potential shale gas exploration target in Nanpanjiang Basin. In this study, X-ray diffraction, field emission scanning electron microscopy, CH4 isothermal adsorption, and nuclear magnetic resonance cryoporometry are intergrated to reveal comprehensive characterization of Linghao Formation shale collected from a well in …

The conventional ore horizon in the McArthur River camp is the HYC Pyritic Shale Member in the lower Barney Creek Formation (~ 1640 Ma) within sub-basin architecture. Rosie is contained within a similar sub-basin architecture, but it occurs in the upper Barney Creek Formation.

29 ມິ.ຖ. 2022 ... Irradiation of the pyritic shale in ferrous iron solutions (0.2 mM) produced sulfate at a rate of 4.2 × 10−9 ± 0.2 × 10−9 mol/m2 per second ( ...Pyrite is a common mineral in shale, coalbeds, and adjacent rocks. However ... Expansion of Pyritic Shales (Article), National Research Council Canada 1972 ...Noun Edit. Shale fragments of Marcellus Shale in talus. shale (countable and uncountable, plural shales). A shell or husk; a cod or pod. quotations ▽. c. 1610s ...The Talvivaara black shale-hosted Ni-Zn-Cu-Co deposit occurs in eastern Finland (Fig. 9.1.1) and is currently the largest sulfidic Ni resource under exploitation in Western Europe.It is a low-grade (0.22 wt% Ni, 0.50 wt% Zn, 0.13 wt% Cu, 0.02 wt% Co, 0.0017 wt% U at Ni cutoff of 0.07 wt%) but very large deposit with total ore resources (measured + indicated + inferred) reaching …Figure 1.1 Expansive pyritic shale model as a step-wise progression during a typical construction project. (a) Elevated water table with overburden materials prior to construction. (b) Water table is lowered and overburden removed as part of the excavation process resulting in increased fracturing and oxidation of available pyrite (H1>H0).Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden. Expansion occurs ...Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden. Expansion occurs ...

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For American frackers that survive, a light is on the horizon. Chesapeake Energy Corp filed for bankruptcy on June 28, ending the pioneer’s run leading the US shale oil and gas industry. Founded in 1989, Chesapeake binged on debt to acquire...Synsedimentary to Diagenetic Cu±Co Mineralization in Mesoproterozoic Pyritic Shale Driven by Magmatic-Hydrothermal Activity on the Edge of the Great Falls Tectonic Zone–Black Butte, Helena ...Pyrite as an Ore of Gold. The most important use of pyrite is as an ore of gold. Gold and pyrite form under similar conditions and occur together in the same rocks. In some deposits small amounts of gold occur as inclusions and substitutions within pyrite. Some pyrites can contain 0.25% gold by weight or more.the pyritic shale and calcareous limestone beds. Also, both the carbonate and sulfuric components need to interact in an aqueous environment, inferring that the dissolution of the carbonate from the calcium carbonate found within the limestone beds is occurring (Martin, 2008). The Mapleton Quarry, located in HuntingdonExpansion of Pyritic Shales. CBD-152. Expansion of Pyritic Shales. Originally published 1972. Weathering of rock formations containing pyrite--an oxidation process--results in a volume increase associated only recently with basement floor heave in Canada. It is now known that pyrite weathering was identified as early as 1950 as a major ...The superhigh-organic-sulfur (SHOS) coals are highly enriched in organic sulfur but depleted in pyritic sulfur. The SHOS coals were deposited in sulfur-rich, iron-poor environments, such as carbonate platforms or in an iron-poor and clastic-starved environment in which algae accumulate. ... The non-marine shale, which may be …Vertical surfaces of shale exposed in trenches, disturbance by blasting, or fault zones that allow air penetration horizontally tend to enhance the rate of weathering and lead to very …Typical Urquhart shale characteristics can be found with increasing distance outwards from the siliceous core into less-altered shales, bands of fine-grained pyrite inter-finger siliceous dolomitic rock types. The footwall has a large amount of pyritic shale, but within the high-grade ore zones, there is minor high-grade pyrite [29,30].minerals. Testing of shale for sulfide content is commonly performed when construction is planned, with limits varying by state and developer specifications. Figure 3. Stereo-optical micrograph of a polished cross section of painted stucco with rust staining showing pyrite sand grain near the surface. Pyrite in Rock Beneath Concrete Structures ….

Pyrite is a common mineral in shale, coalbeds, and adjacent rocks. However ... Expansion of Pyritic Shales (Article), National Research Council Canada 1972 ...The ∼2.7 to 2.6 Ga Roy Hill Shale (Hamersley Basin) is highly pyritic. • Extensive pyrite burial is the result of pulsed S delivery to the Hamersley Basin. • Anomalous S fluxes are attributed to episodes of enhanced subaerial volcanism. • Microbial reduction and burial of S as pyrite oxidizes the surface environment. •The expansive effects of concentrated pyritic zones within the Devonian Marcellus Shale Formation of North America. S.E. Hoover; D. Lehmann. Author and …Moreover, bedding-parallel permeability of the black shale Roy3 and pyritic sandstone Roy4 was below the detection limit of 0.01 millidarcy. Thus, these rocks might have been sealed to hydrocarbon migration since they were last metamorphosed at 2450 to 2000 Ma.Spatial and non-spatial statistical modeling was used to infer co-localized element effects on As binding within soils developed under different pedogenic environments. We hypothesized that spatial patterns of As accumulation in relation to those of matrix elements will uniquely depend on the pedogenic environment.USGS (U.S. Geological Survey) National Geologic Map Database. The age of the Bedford Shale and the Berea Sandstone is changed from Late Devonian and Early Mississippian to Late Devonian only (late Famennian) in the Michigan and Appalachian Basins because of the realignment of the Devonian-Mississippian boundary in the United States with the accepted Devonian-Carboniferous boundary in Europe.We use δ 34 S values of barite and pyrite (pyritic laminae and bulk host shale); center-to-edge variations of δ 13 C and δ 18 O of calcite contained in nodules; and element geochemistry of host shale to geochemically characterize this occurrence. Moreover, we describe center-to-edge textural and mineralogical variations of nodules …Jun 17, 2021 · Synsedimentary to Diagenetic Cu±Co Mineralization in Mesoproterozoic Pyritic Shale Driven by Magmatic-Hydrothermal Activity on the Edge of the Great Falls Tectonic Zone–Black Butte, Helena ... Heave of floor slabs and lightly loaded structures founded on black, pyritic shales has been a severe engineering problem in several places in the world. The geochemical processes responsible for ... Pyritic shale, Three inches (7.6 cm) of differential heave has caused severe structural deformation of a lightly loaded building founded directly on drained black shale bedrock in Ottawa, Canada. Portions of the ..., 3 ກ.ພ. 2022 ... A change order was authorized on January 25, 2022 for the additional work associated with the encountered pyritic shale. This report ..., The distribution and oxidation state of arsenic (As) and selenium (Se) were also determined. The soil used in this study was formed from pyritic shale parent materials on the east side of the California Coast Range. Synchrotron-based X-ray fluorescence microprobe (μ-XRF) was used to generate elemental distribution maps of soil thin sections., Sep 1, 2012 · These mineralized pyritic horizons are intercalated with debris flows derived from synsedimentary movement along the Volcano Valley-Buttress fault zone. Cominco American Inc. delineated a geologic resource of 4.5 Mt at 2.5% Cu and 0.1% Co in the upper sulfide zone and 4 Mt at 4% Cu within the lower sulfide zone. , Expansion of Pyritic Shales (Article), National Research Council Canada 1972 article explaining the cause, effects, and some examples of pyrite-induced swelling (some technical language) Concrete Foundations: Information and …, To test whether this photochemical reaction could have been a geologically relevant process on the early Earth, we repeated our experiments with 2.68 Ga pyritic …, Previous research at the site of a landslip at Mam Tor, Derbyshire, has linked the oxidation of pyrite in Edale Shale to the generation of acid groundwater. Chemical analysis of surface seepages suggests that reactions occur between this acid water and sedimentary minerals, including clays., On 20 December 1983 at 8.40am blast- hole 57 of Blast RN177 prematurely detonated follwed by a violent deflagration of blast- hole 59 at 10.40am. The blastholes were 380mm diameter drilled in black pyritic Mt McRae shale. The blastholes were loaded with ANFO and primed. Blasthole 57 was stemmed and blasthole 59 was not. A poss- ible mechanism which could lead to such a …, The HYC Pyritic Shale Member includes carbonaceous, dolomitic and pyritic siltstone and mudstone deposited in a deep subtidal setting (Bull, 1998). The Upper BCF is composed of thinly bedded/planar laminated, carbonaceous, dolomitic and pyritic siltstone and shale (Davidson and Dashlooty, 1993; Bull, 1998)., Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden., conditions, abundant pyritic shale that contains sulfide minerals is present throughout the rock sequence in the Marcellus Formation. According to Dougherty & Barsotti, (1972), the swelling behavior of pyritic shale has caused considerable structural damage in many areas of the United States. However, standards on how to prevent or mitigate the , SUMMARY. A comprehensive characterization of clay shale behavior requires quantifying both geomechanical and hydromechanical characteristics. This paper presents a comparative laboratory study of different methods to determine the water permeability of saturated Opalinus Clay: (i) pore pressure oscillation, (ii) pressure pulse …, May 12, 2022 · It is a fissile, fine-grained, clastic sedimentary rock comprised of microscopic (less than 1/256 mm in size) mineral particles and phyllosilicate (clay) minerals that were deposited in very low-energy and often relatively anoxic (oxygen-poor) environments, such as deep lakes, ocean basins, and swamps. , The chemical nature of the weathering of pyritic shale is complex and the rate of pyrite oxidation is a function of the mineralogical properties of the pyritic shale, chemical, physical and biological factors such as particle size, temperature of the environment, microbiological activity, oxygen concentration in the gas and water phases (Ritcey ..., To further investigate pyrite weathering in the late Archean, UV irradiation experiments were conducted with 2.68 Ga pyritic shale. We selected pyrite-bearing shale for this experiment because the emergence of Neoarchean crust above sea level ( 27 , 28 , 53 – 55 ) would have exposed large areas of marine sedimentary rocks for chemical weathering., Often inter-grown, massive, radiated, granular, globular, and stalactitic. The mineral pyrite ( / ˈpaɪraɪt / PY-ryte ), [6] or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S 2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. [7], conditions, abundant pyritic shale that contains sulfide minerals is present throughout the rock sequence in the Marcellus Formation. According to Dougherty & Barsotti, (1972), the swelling behavior of pyritic shale has caused considerable structural damage in many areas of the United States. However, standards on how to prevent or mitigate the , was nucleated on a horizon of lag debris, including pyritic fish bones and calcified cartilage of sharks. This lenticular diagenetic horizon appears to mark the abrupt transition at the base of a hard black-shale band. A Dunke10dtettd specimen was recovered from this level by G. Kampouris. , In Green River oil shale, sulfur occurs in both inorganic and organic combinations; 70 to 85% of the sulfur is present as pyrite, and most of the remaining sulfur is present as organic sulfur., The distribution and oxidation state of arsenic (As) and selenium (Se) were also determined. The soil used in this study was formed from pyritic shale parent materials on the east side of the California Coast Range. Synchrotron-based X-ray fluorescence microprobe (μ-XRF) was used to generate elemental distribution maps of soil thin sections., Sep 1, 2012 · These mineralized pyritic horizons are intercalated with debris flows derived from synsedimentary movement along the Volcano Valley-Buttress fault zone. Cominco American Inc. delineated a geologic resource of 4.5 Mt at 2.5% Cu and 0.1% Co in the upper sulfide zone and 4 Mt at 4% Cu within the lower sulfide zone. , Foundation Engineering. Pyrite oxidation and expansion in the New Albany black shale have caused serious foundation problems in numerous buildings and structures constructed in the black shale soil horizons in various parts of Kentucky. Pyrite oxidizes, causing various secondary sulfates to form when excavated shale or shale fill is exposed to ..., To test whether this photochemical reaction could have been a geologically relevant process on the early Earth, we repeated our experiments with 2.68 Ga pyritic …, The Evangelical Hospital located in Lewisburg, Pennsylvania has experienced distress in the form of cracked floor slabs and displaced structural steel due to swelling of the underlying fill material and natural bedrock formation. The bedrock consisted of black, pyritic, calcareous shale from the Marcellus Formation of the Hamilton Group (Devonian Age). The fill materials beneath the cracked ..., As they grow, the new sulfate minerals push against the surrounding rock, causing it to swell and crack. This causes damage in two main ways: If pyrite or pyrrhotite are present in the rocks underneath buildings, the swelling can push on the foundation, walls, and basement floor of the building, causing cracks and other structural damage., The wide distribution of δ 34 S values from the jarosite samples, which are consistently heavier than the corresponding pyritic shale values, indicates a partial sulphate input from isotopically heavier sources, potentially modern seawater or artificial fertilisers (Fig. 9). Download : Download high-res image (300KB), black shale, also called Carboniferous Shale, variety of shale that contains abundant organic matter, pyrite, and sometimes carbonate nodules or layers and, in some locations, concentrations of copper, nickel, uranium, and vanadium. Fossils are rare in the shale and either are replaced by pyrite or are preserved as a film of graphite. Black shales occur in …, Oehler JH (1977) Microflora of the H.Y.C. Pyritic Shale Member of the Barney Creek Formation (McArthur Group), Middle Proterozoic of northern Australia. Al-cheringa 1: 315–349. Google Scholar Park RG (1980) Origin of horizontal structure in high-grade Archaean terrains., pyritic sulfur to sulfate through Fe 3+ derived from the photooxidation of dissolved ferrous iron. The geologic relevance of this photochemi-cal process was further investigated by conducting photooxidation experiments with 2.68 Ga pyritic shale to simulate chemical weath-ering of pyrite-bearing Archean rocks. A photogeochemical model, These mineralized pyritic horizons are intercalated with debris flows derived from synsedimentary movement along the Volcano Valley-Buttress fault zone. Cominco American Inc. delineated a geologic resource of 4.5 Mt at 2.5% Cu and 0.1% Co in the upper sulfide zone and 4 Mt at 4% Cu within the lower sulfide zone. ... Geology and origin of shale ..., Jun 29, 2022 · Pyrite is a mineral that is commonly found in shale gas reservoirs. Its genetic mechanism and impact on pore and organic matter in shale gas reservoirs are critical for shale gas exploration. This study selects the Longmaxi shale (Lower Silurian) in the Changning area of the southern Sichuan Basin by comprehensively using a scanning electron microscope (SEM), X-ray diffraction (XRD), total ... , Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden., Other pyritic material (yellow) is attached or occurs close to Gunflintia sheaths; this has neither a crystalline nor cellular morphology and is interpreted here as pyritized EPSs. (Inset) Single FIB-SEM slice indicating the hollow nature of the pyritic Gunflintia sheaths (G) and saprophytic heterotroph (arrow), as well as inferred pyritized EPSs.