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    This study explored the links between host rock composition, hydrothermal fluid composition (particularly pH), and the resulting ore minerals and deposits. The progressive water–rock reaction between 1 kg of initially acidic, condensed magmatic vapour and a series of different rock compositions was modelled with CHILLER (Reed, 1982, Reed, 1998), and follows the design of the water-rock reactions of Reed (1997). The thermodynamic data used in the numerical experiments are from the database SOLTHERM.H08 (Reed and Palandri, 2013). Data and calculations within SOLTHERM include: equilibrium constants calculated with SUPCRT92 (Johnson et al., 1992); mineral thermodynamic data for silicates, oxides, hydroxides, carbonates, gases (Holland and Powell, 1998) and sulphides (Shock, 2007). Mineral solid solutions are represented by end-member compositions that are mixed using an ideal multisite mixing scheme. Rock compositions used in the modelling represent a sub-alkaline andesitic control, and a number of alkaline compositions associated with world-class Au deposits. All starting rock compositions are derived from whole rock geochemical data, and have been recalculated to a 100% basis without TiO2 or P2O5 (excluded as minor phases with little to no effect on hydrothermal mineral assemblages). Original total Fe (as Fe2O3) has been recalculated to FeO and Fe2O3 using the method of Müller et al. (2001). The andesite is representative of calc-alkaline, silica saturated compositions, and is derived from and discussed in detail in Reed (1997). The Luise “Phonolite” (a trachyandesite using the Le Maitre et al., 1989 TAS plot; Fig. 1) and Trachyandesite are from the vicinity of the Ladolam epithermal Au deposit, Lihir Island, Papua New Guinea (Müller et al., 2001). The Porgera Mugearite and Feldspar Porphyry represent unaltered host rock compositions (Richards, 1990) from the Porgera Au deposit (Papua New Guinea). The Cripple Creek Phonolite is part of the host suite to the Cripple Creek epithermal Au deposit, Colorado (Kelley et al., 1998). The Savo trachyte (Smith et al., 2009) represents a typical host rock of the active hydrothermal system (Smith et al., 2010), on Savo island, Solomon Islands. With the exception of the Andesite, all compositions are alkaline using the total alkali versus silica definition of Irvine and Baragar (1971). The Savo sample is not associated with known epithermal Au mineralisation; this composition was selected on the grounds that it represents an evolved (SiO2-rich) silica-saturated, alkaline composition. The initial fluid composition is based on a condensate from Augustine volcano (Symonds et al., 1990) mixed 1:10 with pure water (Reed, 1997; Table 2). A single starting fluid for all models was chosen so as to demonstrate the effect of host rock alone.

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    The data set consists of rock samples collected from Coquetdale, Coldstream and Whitrope Burn from 2013-2014; milled material is included. There is an Excel spreadsheet of sample numbers with location, sample height on log, d13C data and %C. There are scans of field logs from Coquetdale, Coldstream and Whitrope Burn, and Illustrator drawn logs from Coldstream which include samples collected at a later date. Scans of thin sections are also included. (thin sections to be kept at Leicester for the time being – still being worked on for papers.) Each locality folder has an Excel spreadsheet detailing samples, sample height, %C and bulk and specific d13C values. These data were used to interpret the environment in which early tetrapods have been found in the early Carboniferous. These data supported the MPhil thesis 'In an alternating marine and non-marine depositional setting, where and how are early Carboniferous tetrapods preserved?' by Sherwin, 2018, and one publication including data from Whitrope Burn - Richards et al., 2018, (https://doi.org/10.1017/S1755691018000166).

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    The data set consists of rock samples collected from Burnmouth, a core drilled at Norham, from Crumble Edge, Willie's Hole and Nova Scotia from 2012-2016; milled material is included. There is an Excel spreadsheet of sample numbers with location, sample height on log, lithology and fossil content. Scans of field logs from Burnmouth, Crumble Edge, Edington Mill, Pease Bay (UK) and locations in Nova Scotia, and overview drawn-up logs from Burnmouth, Norham, Crumble Edge and Willie's Hole are included. Scans of thin section scans are also included. There is a spreadsheet containing geochemistry data - sample numbers with lithology and %C, %S, d13C. These data were used to interpret the environment in which early tetrapods have been found in the early Carboniferous. Publications include: Bennett et al., 2016 (doi: 10.1111/sed.12280); Bennett et al., 2017 (http://dx.doi.org/10.1016/j.palaeo.2016.12.018 0031-0182); Clack et al., 2016, (DOI: 10.1038/s41559-016-0002); Kearsey et al., 2016 (http://dx.doi.org/10.1016/j.palaeo.2016.05.033) ; Clack et al., 2018, (doi:10.1017/S1755691018000087); Millward et al., 2018 (doi: 10.1111/sed.12465); Ross et al., 2018 (https://doi.org/10.1017/S1755691018000142)

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    Publications linked to the Grant: Holwell DA, Keays RR, McDonald I and Williams MR. 2015. Extreme Enrichment of Se, Te, PGE and Au in Cu sulfide microdroplets: evidence from LA-ICP-MS analysis of sulfides in the Skaergaard Intrusion, East Greenland Contribution to Mineralogy and Petrology. doi: 10.1007/s00410-015-1203-y. 2) Smith JW, Holwell DA, McDonald I, Boyce AJ. 2016. The application of S isotopes and S/Se ratios in determining ore-forming processes of Magmatic Ni-Cu-PGE sulfide deposits: a cautionary case study from the northern Bushveld Complex Ore Geology Reviews, 73, 148–174 10.1016/j.oregeorev.2015.10.022. Jenkin GRT, Al-Bassam AZM, Harris, RC, Abbott, AP, Smith DJ, Holwell DA, Chapman RJ and Stanley CJ. 2015. The application of Deep Eutectic Solvent Ionic liquids for environmentally friendly dissolution and recovery of precious metals. Minerals Engineering, doi: 10.1016/j.mineng.2015.09.026. Hughes, H. S.R., McDonald, I., Faithfull, J. W., Upton, B. G..J., and Loocke, M. (2016) Cobalt and precious metals in sulphides of Peridotite Xenoliths and inferences concerning their distribution according to geodynamic environment: a case study from the Scottish lithospheric mantle. Lithos, 240-3, pp. 202-227. doi:10.1016/j.lithos.2015.11.007. Abbott, A.P., Harris, R.C., Holyoak, F., Frisch, G., Hartley, J. and Jenkin, G.R., 2015. Electrocatalytic recovery of elements from complex mixtures using Deep Eutectic solvents. Green Chemistry, 17(4), pp.2172-2179. DOI: 10.1039/C4GC02246G

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    The data were produced by Joe Emmings, NERC-funded PhD student at the University of Leicester and British Geological Survey, between 2014 and 2017. Authors of these data: Joe Emmings a, b; Sarah Davies a; Christopher Vane b; Melanie Leng b, c; Vicky Moss-Hayes b; Michael Stephenson b a School of Geography, Geology and the Environment, University of Leicester, University Road, Leicester, LE1 7RH, UK. b British Geological Survey, Keyworth, Nottingham, NG12 5GG, UK. c School of Biosciences, Centre for Environmental Geochemistry, University of Nottingham, Sutton Bonington Campus, Leicestershire LE12 5RD, UK. Data include: 1) A range of photographs from the outcrop Hind Clough and boreholes MHD4 and Cominco S9, sample photographs, thin section scans, microphotographs (transmitted light and scanning electron microscopy) and hand specimen descriptions; 2) The results of 100 analyses from the outcrop Hind Clough and boreholes MHD4 and Cominco S9; x-ray fluorescence major and trace element concentrations, RockEval pyrolysis measurements, x-ray diffraction traces and LECO elemental C and S data. These data were interpreted together with 20 drill-core samples previously acquired from Hind Clough ('HC01' prefix). See http://dx.doi.org/10.5285/c39a32b2-1a30-4426-8389-2fae21ec60ad for further information regarding this drill-core dataset. Acknowledgements: This study was funded by NERC grant NE/L002493/1, a part of the Central England Training Alliance (CENTA). This study also received CASE funding from the BGS. Nick Riley (Carboniferous Ltd) is thanked for sharing his expertise, particularly regarding the field identification of marine faunas. Charlotte Watts is thanked for providing field assistance. Nick Marsh, Tom Knott and Cheryl Haidon are thanked for providing expertise and assistance during inorganic geochemical and mineralogical analyses.

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    These data accompany a manuscript, titled: Stream and Slope Weathering Effects on Organic-rich Mudstone Geochemistry and Implications for Hydrocarbon Source Rock Assessment: A Bowland Shale Case Study All files with prefix 'Man_1' relate to this submission. The manuscript was submitted to the journal Chemical Geology in December 2016. Data include: 1) A range of photographs from the outcrop, drill cores, sub-samples, 'weathering grades' and thin section microphotographs from the Bowland Shale; 2) The results of mineralogical (whole rock powder x-ray diffraction; XRD) analyses for 18 subsamples; 3) The results of inorganic geochemical analyses (LECO elemental C and S, x-ray fluorescence major and trace elements) for 18 subsamples; 4) The results of organic geochemical analyses (Rock-Eval pyrolysis, d13Corg) for 20 subsamples; 5) RStudio scripts used to conduct statistical analyses (e.g., Principal Components Analysis) and generation of figures.

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    This is a geochemical dataset accompanying Emmings, J., Poulton, S., Vane, C., Davies, S., Jenkin, G., Stephenson, M., Leng, M., Lamb, A., Moss-Hayes, V. A Mississippian Black Shale Record of Redox Oscillation. Palaeogeography, Palaeoclimatology, Palaeoecology [submitted July 2019]. This dataset includes RockEval pyrolysis, major and trace element (XRF), Fe speciation, C, N and S isotopes and S species analyses through the Upper Bowland Shale in the Craven Basin (Lancashire, UK). This research was conducted by Joe Emmings, PhD researcher at the University of Leicester and British Geological Survey (BGS) between 2014-2018, and as a post-doctoral research associate (PDRA) at the British Geological Survey (2018-2021). The PhD research was funded by the Natural Environment Research Council (NERC), as part of the Central England Training Alliance (CENTA) [grant no. NE/L002493/1] and received CASE funding from the BGS. PDRA research was funded by the British Geological Survey. Reproduction or manipulation of these data in future analyses should cite one or more of the following related publications (as necessary): Emmings, J., 2018. Controls on UK Lower Namurian Shale Gas Prospectivity: Understanding the Spatial and Temporal Distribution of Organic Matter in Siliciclastic Mudstones. PhD Thesis, University of Leicester. Emmings J. et al. 2017. Stream and slope weathering effects on organic-rich mudstone geochemistry and implications for hydrocarbon source rock assessment: a Bowland Shale case study. Chemical Geology. 471. 74-91. Emmings, J. et al., 2019a. From Marine Bands to Hybrid Flows: Sedimentology of a Mississippian Black Shale. Sedimentology, [Accepted ms.]. Emmings, J.F. et al., 2019b. Controls on amorphous organic matter type and sulphurization in a Mississippian black shale. Review of Palaeobotany and Palynology, 268: 1-18. Emmings, J.F. et al. A Mississippian black shale record of redox oscillation. Palaeogeography, Palaeoclimatology, Palaeoecology [submitted July 2019] Co-workers: Sarah Davies (University of Leicester) - Primary PhD supervisor, sedimentology Chris Vane (BGS) - PhD supervisor, RockEval pyrolysis Mel Leng (BGS & University of Nottingham) - PhD supervisor, C & S isotopes Mike Stephenson (BGS) - PhD supervisor Simon Poulton (University of Leeds) - Fe speciation Gawen Jenkin (University of Leicester) - PhD supervisor Vicky Moss-Hayes (BGS) - RockEval pyrolysis Angela Lamb (BGS) - S isotopes