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Nash Formation

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Journal Article

Precambrian stromatolites, bioherms and reefs in thelower half of the Nash Formation, Medicine Bow Mountains, Wyoming

S. H. Knight
Published: 01 October 1968
Rocky Mountain Geology (1968) 7 (2): 73–116.
...S. H. Knight Abstract Early Proterozoic stromatolitic metadolomite bioherms and reefs occur in the Nash Formation, 6,500 feet thick, which is part of a 25,000-ft sequence of metasediments forming the core of the range. The formation is believed to be not less than 1,700 m.y. old. Some 150 bioherms...
View PDF for article title, Precambrian stromatolites, bioherms and reefs in thelower half of the <span class="search-highlight">Nash</span> <span class="search-highlight">Formation</span>, Medicine Bow Mountains, Wyoming
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Journal Article

Preliminary report on the Precambrian stromatolites in the Nash Formation, Medicine Bow Mountains, Wyoming

Samuel H. Knight, David K. Keefer
Published: 01 April 1966
Rocky Mountain Geology (1966) 5 (1): 1–11.
...Samuel H. Knight; David K. Keefer Abstract The field relations and megascopic character of three types of stromatolites, and the bioherms, occurring in the lower half of what is herein defined as the Nash Formation, are described and illustrated. The Nash Formation is part of a succession...
View PDF for article title, Preliminary report on the Precambrian stromatolites in the <span class="search-highlight">Nash</span> <span class="search-highlight">Formation</span>, Medicine Bow Mountains, Wyoming
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Journal Article

Paleoproterozoic stromatolites, Hurwitz Group, Quartzite Lake area, Northwest Territories, Canada

H J Hofmann, A Davidson
Published: 01 March 1998
Canadian Journal of Earth Sciences (1998) 35 (3): 280–289.
DOI: https://doi.org/10.1139/e97-103
... other known early Paleoproterozoic stromatolite occurrences in North America: the Kona Formation of Michigan, and the Nash Formation in southern Wyoming. They also are similar to stromatolites in probable coeval Jatulian carbonates in Karelia on the Baltic Shield, and possibly to stromatolites...
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Image
The Dolyhir and Nash Scar Limestone Formation and its upper contact with the Coalbrookdale Formation. (a) Upper half (c. 10 m) of the Dolyhir and Nash Scar Limestone between Dolyhir Quarry sections (S4 and S5). The transition into the silty mudstones of the Coalbrookdale Formation can be seen at the very top of the section (arrow). (b) Tectonized trilobite accumulations (white shelly material) dominated by the illaenid trilobite Bumastus? phrix (scale bar 1 cm). Basal Coalbrookdale Formation, Dolyhir Quarry (S5). (c) Circular masses of the coralline algae (Craticula gotlandica), associated with silty mudstone laminations and rudstone (scale bar 5 cm), Dolyhir Quarry (S4). (d) The transition between the Dolyhir and Nash Scar Limestone and Coalbrookdale formations, showing a scoured starvation surface at the top of the Dolyhir and Nash Scar Limestone and an infilling pocket of trilobitic silty mudstone, Dolyhir Quarry (S5). (e) A conspicuous development of the coral Coenites sp. (possibly from the upper Bryozoan Bed of Garwood and Goodyear [5]), Dolyhir Quarry (S4).

The Dolyhir and Nash Scar Limestone Formation and its upper contact with th...

Published: 10 July 2021
Figure 8 The Dolyhir and Nash Scar Limestone Formation and its upper contact with the Coalbrookdale Formation. (a) Upper half (c. 10 m) of the Dolyhir and Nash Scar Limestone between Dolyhir Quarry sections (S4 and S5). The transition into the silty mudstones of the Coalbrookdale Formation can
Image
Nash Point rock platform in South Wales looking east. Note formation of cuestas and scarps up to 5 m high cut across the platform.

Nash Point rock platform in South Wales looking east. Note formation of cue...

Published: 01 May 2007
Figure 4. Nash Point rock platform in South Wales looking east. Note formation of cuestas and scarps up to 5 m high cut across the platform.
Image
Typical lithologies encountered at Dolyhir Quarry. Scale bar is 5 mm. (a) Basal Dolyhir Rudite Member showing quartzite and dolerite clasts within a matrix of crinoids in secondary calcite (XPL). (b) The Dolyhir and Nash Scar Limestone Formation composed of reef-derived allochthonous bioclasts, notably the coral Coenites sp., as well as irregular to subspherical masses of the algae Craticula gotlandica. (c) Silty mudstones within the Dolyhir and Nash Scar Limestone Formation containing a distinctive fauna of brachiopods, crinoids, corals, and trilobites. See Figures 2 and 7 for the location of the thin sections.

Typical lithologies encountered at Dolyhir Quarry. Scale bar is 5 mm. (a) B...

Published: 10 July 2021
Figure 5 Typical lithologies encountered at Dolyhir Quarry. Scale bar is 5 mm. (a) Basal Dolyhir Rudite Member showing quartzite and dolerite clasts within a matrix of crinoids in secondary calcite (XPL). (b) The Dolyhir and Nash Scar Limestone Formation composed of reef-derived allochthonous
Image
A simplified geological map of the Strinds and Dolyhir quarries, showing the location of key sections (Strinds S1; Dolyhir S1 to S4) and the distribution of the Neoproterozoic basement rocks (Strinds and Yat Wood formations), the Dolyhir Rudite Member, the Dolyhir and Nash Scar Limestone Formation, and the Coalbrookdale Formation. Borehole locations and lithostratigraphic units encountered, alongside a selection of representative thicknesses, are shown. Thickness values (m) are given to the left of the borehole with the youngest unit at the top (f = faulting within the borehole records). The thicknesses have not been corrected for the typically gentle dip of the Silurian succession (not reported in borehole records). Note that the Dolyhir Rudite Member occurs between the basement and the Dolyhir and Nash Scar Limestone Formation but is only located here within borehole records and at well-exposed sections. The map was modified from those given in Garwood and Goodyear [5], Woodcock [3], and Brewer et al. [33].

A simplified geological map of the Strinds and Dolyhir quarries, showing th...

Published: 10 July 2021
Figure 3 A simplified geological map of the Strinds and Dolyhir quarries, showing the location of key sections (Strinds S1; Dolyhir S1 to S4) and the distribution of the Neoproterozoic basement rocks (Strinds and Yat Wood formations), the Dolyhir Rudite Member, the Dolyhir and Nash Scar Limestone
Journal Article

Shallow-Seated Dissolution of Bedded Evaporites in Northern Delaware Basin

Steven J. Lambert
Journal: AAPG Bulletin
Published: 01 April 1981
AAPG Bulletin (1981) 65 (4): 764.
DOI: https://doi.org/10.1306/2F919A76-16CE-11D7-8645000102C1865D
...Steven J. Lambert ABSTRACT Studies of boreholes penetrating the Dewey Lake, Rustler, and uppermost Salado Formations in the northern Delaware basin (southeastern New Mexico) have investigated subsurface dissolution of bedded evaporites in the vicinity of Nash Draw, a depression 5 to 10 mi (8 to 16...
View PDF for article title, Shallow-Seated Dissolution of Bedded Evaporites in Northern Delaware Basin
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Journal Article

Biostratigraphy of Vicksburgian Equivalent at Toledo Bend Dam Site, Louisiana and Texas

Don R. Anderson
Journal: AAPG Bulletin
Published: 01 October 1965
AAPG Bulletin (1965) 49 (10): 1752–1753.
DOI: https://doi.org/10.1306/A66337DE-16C0-11D7-8645000102C1865D
... are proposed: (1) the Danville Landing beds, Mosley Hill Formation, Sandel Formation, and Nash Creek Formation are considered to belong to the Spondylus dumosus zone introduced by Cheetham in 1957 for a series of beds in Florida and Alabama; (2) within the assemblage zone characterized by Spondylus dumosus...
View PDF for article title, Biostratigraphy of Vicksburgian Equivalent at Toledo Bend Dam Site, Louisiana and Texas
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Image
Schematic southwest-northeast profile across the southern Central Zone of the Damara Orogen, showing progressive thinning and pinch out of formations to the east. Approximate unit thicknesses are from Nash (1971), Blaine (1977) and Miller (2008).

Schematic southwest-northeast profile across the southern Central Zone of t...

Published: 01 March 2011
Figure 2. Schematic southwest-northeast profile across the southern Central Zone of the Damara Orogen, showing progressive thinning and pinch out of formations to the east. Approximate unit thicknesses are from Nash (1971) , Blaine (1977) and Miller (2008) .
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Sedimentary logs from the Old Radnor and Presteigne study area, showing the key sections that contain the Dolyhir and Nash Scar Limestone Formation and the immediately under- and overlying successions. δ13Ccarb values are given, alongside the location of conodont samples and illustrated thin sections.

Sedimentary logs from the Old Radnor and Presteigne study area, showing the...

Published: 10 July 2021
Figure 7 Sedimentary logs from the Old Radnor and Presteigne study area, showing the key sections that contain the Dolyhir and Nash Scar Limestone Formation and the immediately under- and overlying successions. δ 13 C carb values are given, alongside the location of conodont samples
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Simplified geologic map of the Blackbird district and vicinity, showing the locations of major strata-bound sulfide deposits and strata-bound or discordant iron oxide deposits. Geology from Tysdal et al. (2003) and Lund and Tysdal (2006). Ages of the augen gneiss body and the Apple Creek Formation are from Lund et al. (2004) and Link et al. (2006), respectively. Locations of sulfide deposits are from Reed and Herdlick (1947) and Nash and Hahn (1989); iron oxide deposits are from Modreski (1985) and Nash (1989). Other sulfide deposits not shown here but mentioned in the text (e.g., Dandy, Horseshoe) are located between the Merle and Blacktail deposits (see Reed and Herdlick, 1947; Vhay, 1948; Bennett, 1977).

Simplified geologic map of the Blackbird district and vicinity, showing the...

Published: 01 May 2006
Creek Formation are from Lund et al. (2004) and Link et al. (2006), respectively. Locations of sulfide deposits are from Reed and Herdlick (1947) and Nash and Hahn (1989); iron oxide deposits are from Modreski (1985) and Nash (1989). Other sulfide deposits not shown here but mentioned in the text (e.g
Image
Simplified geologic map of the Blackbird district and vicinity, showing the locations of major strata-bound sulfide deposits and strata-bound or discordant iron oxide deposits. Geology from Tysdal et al. (2003) and Lund and Tysdal (2006). Ages of the augen gneiss body and the Apple Creek Formation are from Lund et al. (2004) and Link et al. (2006), respectively. Locations of sulfide deposits are from Reed and Herdlick (1947) and Nash and Hahn (1989); iron oxide deposits are from Modreski (1985) and Nash (1989). Other sulfide deposits not shown here but mentioned in the text (e.g., Dandy, Horseshoe) are located between the Merle and Blacktail deposits (see Reed and Herdlick, 1947; Vhay, 1948; Bennett, 1977).

Simplified geologic map of the Blackbird district and vicinity, showing the...

Published: 01 March 2006
Creek Formation are from Lund et al. (2004) and Link et al. (2006) , respectively. Locations of sulfide deposits are from Reed and Herdlick (1947) and Nash and Hahn (1989) ; iron oxide deposits are from Modreski (1985) and Nash (1989) . Other sulfide deposits not shown here but mentioned
Image
Sedimentary logs from the Old Radnor and Presteigne study area, showing the key sections that contain the Dolyhir Rudite Member of the Dolyhir and Nash Scar Limestone Formation and the immediately under- and overlying successions. δ13Ccarb values are given, alongside the location of conodont samples and illustrated thin sections.

Sedimentary logs from the Old Radnor and Presteigne study area, showing the...

Published: 10 July 2021
Figure 2 Sedimentary logs from the Old Radnor and Presteigne study area, showing the key sections that contain the Dolyhir Rudite Member of the Dolyhir and Nash Scar Limestone Formation and the immediately under- and overlying successions. δ 13 C carb values are given, alongside the location
Image
Overview of the study area. (a) Simplified geological map showing the area between Old Radnor and Presteigne and the coeval succession of the Malvern Hills. Note that the red dashed lines highlight the approximate trends of the Church Stretton Fault Zone (CSFZ) and Malvern Line (ML). Contains British Geological Survey materials © UKRI (2021). (b) The age and thickness of the succession encountered within the study area, based upon the results of the study herein. Early (e), middle (m), and late (l) subdivisions have been given for the stages, as have the internationally recognized stage slices [19, 20]. (c) Palaeogeographic context of the Old Radnor and Presteigne study area during middle Sheinwoodian times; estimated palaeolatitude of study area 13°S of the equator [31, 94]. CSFZ = Church Stretton Fault Zone; MH = Malvern Hills; ML = Malvern Line; Pem. = Pembrokeshire. (d) The location of the main outcrops investigated. Note that the Dolyhir Rudite Member occurs between the Folly Sandstone and Dolyhir and Nash Scar Limestone formations and between the Neoproterozoic basement and the Dolyhir and Nash Scar Limestone Formation but is of insufficient thickness to illustrate on this map.

Overview of the study area. (a) Simplified geological map showing the area ...

Published: 10 July 2021
. (d) The location of the main outcrops investigated. Note that the Dolyhir Rudite Member occurs between the Folly Sandstone and Dolyhir and Nash Scar Limestone formations and between the Neoproterozoic basement and the Dolyhir and Nash Scar Limestone Formation but is of insufficient thickness
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Ternary Co-Cu-(Au × 1,000) plot showing bulk compositions of mineralized samples from the Idaho cobalt belt. Data from this study comprise 48 sulfide-rich samples from 14 deposits in the Blackbird district (see online App. 1), seven samples from the Iron Creek area, and one sample each from the Haynes-Stellite and Conicu tourmalinized breccia bodies. Fields for mineralized samples from the district are mostly for the Merle and Sunshine deposits (Nash et al., 1988), distinguished here based on weakly mineralized (0.1–1.0 wt % Co + Cu; n = 101) and strongly mineralized (&gt;1.0 wt % Co + Cu; n = 54) bulk compositions. Average production figures for the period 1949 to 1960 are from Nash and Hahn (1989). Unmined reserves and resources are from Bennett (1977) and Bending and Scales (2001), respectively; reserves and resources for the Ram and Black Pine deposits are from Formation Metals Inc. (2009).

Ternary Co-Cu-(Au × 1,000) plot showing bulk compositions of mineralized sa...

Published: 01 September 2012
from the Haynes-Stellite and Conicu tourmalinized breccia bodies. Fields for mineralized samples from the district are mostly for the Merle and Sunshine deposits ( Nash et al., 1988 ), distinguished here based on weakly mineralized (0.1–1.0 wt % Co + Cu; n = 101) and strongly mineralized (>1.0 wt
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Trace element variation diagrams (normalization after Pearce 1983) for: (a) the alkaline igneous rocks of the Commerce Mountain and adjacent areas. CF, Crowsnest Formation; RR, Rainy Ridge; CM, Commerce Mountain; and TR, Trachyte Ridge. (b) Comparative data from the Kenyan rift (Baker et al. 1977) and Shonkin Sag (Nash and Wilkinson 1971).

Trace element variation diagrams (normalization after Pearce 1983 ) for: (...

Published: 01 March 2000
Fig. 9. Trace element variation diagrams (normalization after Pearce 1983 ) for: ( a ) the alkaline igneous rocks of the Commerce Mountain and adjacent areas. CF, Crowsnest Formation; RR, Rainy Ridge; CM, Commerce Mountain; and TR, Trachyte Ridge. ( b ) Comparative data from the Kenyan rift
Journal Article

The Silurian Transgression of a Palaeoshoreline: The Area between Old Radnor and Presteigne, Welsh Borderlands

David C. Ray, Emilia Jarochowska, Helen E. Hughes, Anna L. Claussen, Arthur C. Tingley, John Moseley, Oskar Bremer
Journal: Lithosphere
Publisher: GSW
Published: 10 July 2021
Lithosphere (2021) 2021 (1): 7866176.
DOI: https://doi.org/10.2113/2021/7866176
...Figure 8 The Dolyhir and Nash Scar Limestone Formation and its upper contact with the Coalbrookdale Formation. (a) Upper half (c. 10 m) of the Dolyhir and Nash Scar Limestone between Dolyhir Quarry sections (S4 and S5). The transition into the silty mudstones of the Coalbrookdale Formation can...
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Image
Rare earth element diagrams for (a) the alkaline igneous rocks of the Commerce Mountain and adjacent areas. CF, Crowsnest Formation volcanic rocks; RR, Rainy Ridge; CM, Commerce Mountain; TR, Trachyte Ridge. (b) Comparative data from the Kenyan rift (Baker et al. 1977) and Shonkin Sag (Nash and Wilkinson 1971); only La, Ce, and Nd data are available and shown for Shonkin Sag.

Rare earth element diagrams for ( a ) the alkaline igneous rocks of the Com...

Published: 01 March 2000
Fig. 10. Rare earth element diagrams for ( a ) the alkaline igneous rocks of the Commerce Mountain and adjacent areas. CF, Crowsnest Formation volcanic rocks; RR, Rainy Ridge; CM, Commerce Mountain; TR, Trachyte Ridge. ( b ) Comparative data from the Kenyan rift ( Baker et al. 1977 ) and Shonkin
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Map of Liberty Hills showing paleomagnetic sampling sites and collection site of dated granite clast. Dashed line shows axial trace of the Liberty Hills anticline. A contoured stereoplot of poles to bedding reveals the subhorizontal nature of the fold axis. Inset: Location of Liberty Hills within the Ellsworth Mountains and the location of the sampling sites of Watts and Bramall (1981) in the Frazier Ridge Formation and Grunow et al. (1987) in the Nash Hills.

Map of Liberty Hills showing paleomagnetic sampling sites and collection si...

Published: 01 July 2000
Hills within the Ellsworth Mountains and the location of the sampling sites of Watts and Bramall ( 1981 ) in the Frazier Ridge Formation and Grunow et al. ( 1987 ) in the Nash Hills.