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[Abstract Quartz‐rich sandstones can be produced through multiple sedimentary processes, potentially acting in combination, such as extensive sedimentary recycling or intense chemical weathering. Determining the provenance of such sedimentary rocks can be challenging due to low amounts of accessory minerals, the fact that the primary mineralogy may have been altered during transport, storage or burial and difficulties in the recognition of polycyclic components. This study uses zircon and apatite U‐Pb geochronology, apatite trace elements, zircon‐tourmaline‐rutile indices and petrographic observations to investigate the sedimentary history of mineralogically mature mid‐Carboniferous sandstones of the Tullig Cyclothem, Clare Basin, western Ireland. The provenance data show that the sandstones have been dominantly and ultimately sourced from three basement terranes: older Laurentian‐ associated rocks (ca. 900–2500 Ma) which lay to the north of the basin, peri‐Gondwanan terranes (ca. 500–700 Ma) to the south and igneous intrusive rocks associated with the Caledonian Orogenic Cycle (ca. 380–500 Ma). However, the multi‐proxy approach also helps constrain the sedimentary history and suggests that not all grain populations were derived directly from their original source. Grains with a Laurentian or a Caledonian affinity have likely been recycled through Devonian basins to the south. Grains with a peri‐Gondwanan affinity appear to be first cycle and are potentially derived from south/southwest of the basin. Taken as a whole, these data are consistent with input into the basin from the south and southwest, with the reworking of older sedimentary rocks, rather than intensive first‐cycle chemical weathering, likely explaining the compositional maturity of the sandstones. This study highlights the need for a multi‐proxy provenance approach to constrain sedimentary recycling, particularly in compositionally mature sandstones, as the use of zircon geochronology alone would have led to erroneous provenance interpretations. Zircon, together with U‐Pb geochronology from more labile phases such as apatite, can help distinguish first‐cycle versus polycyclic detritus., This multi‐proxy provenance approach identifies partly recycled sandstones in the mid‐Carboniferous Tullig Cyclothem of the Clare Basin. Taken as a whole, these data are consistent with input into the basin from the south and southwest, with first cycle peri‐Gondwanan grains and recycling of Caledonian and Laurentian grains through Devonian basins to the south. ]

Sediment delivery and supply are explicitly controlled by variations in broad-scale processes such as climate, tectonics and eustasy. These in turn influence fluvial processes and hinterland evolution. A bespoke multi-proxy approach (integrating apatite and zircon U-Pb geochronology, trace elements in apatite, and Pb-in-K-feldspar provenance tools) coupled with outcrop investigation is used to constrain the temporal trends in sediment delivery to channel sandstones of the fluvio-estuarine mid-Viséan Mullaghmore Sandstone Formation, Ireland. Provenance data indicate unique detrital signatures for all sampled horizons, indicating the fluctuating nature of sediment supply to this medium-sized basin. Tectonism and/or abrupt relative sea-level fall likely caused fluvial rejuvenation, resulting in local basement sourcing of the initial fill. Older and more distal sources, such as the Nagssugtoqidian Belt of East Greenland, become more prominent in stratigraphically younger channel sandstones suggesting catchment expansion. Paleoproterozoic to Mesoproterozoic sources are most dominant, yet the detrital grain cargo varies in each channel sandstone. Proximal sources such as the Donegal Batholith and Dalradian Supergroup are variable and appear to switch on and off. These signal shifts are likely the result of channel migration and paleoclimatic fluctuation. A monsoonal climate and large-scale wildfire events (evidenced by fusain) likely contributed to modify plant cover, intensify erosion, and increase run-off and sediment delivery rates from specific areas of the hinterland.

Multiple factors (e.g. source rock composition, climate, nature/scale of sedimentary system) influence the volume and composition of sediment delivered to basins. Fluctuations in these parameters produce cryptic source signals which can vary within the same sedimentary system. Bespoke multi-proxy provenance approaches, targeted at minerals of variable stability, allow for an assessment of natural biasing (recycling) and intra-basinal spatial variations. Provenance of fluvial/deltaic sandstones (Mullaghmore Sandstone Formation) in the NW Carboniferous Basin, Ireland, has been constrained using zircon and apatite U–Pb geochronology, trace elements in apatite and Pb-in-K-feldspar analysis. Zircon U–Pb grain populations are consistent with feldspar data, suggesting Proterozoic basement highs offshore Ireland and Scotland were the main contributor with minor supply from Archean–Paleoproterozoic rocks of Greenland/NW Scotland and Caledonian-aged rocks. However, apatite data show a much larger proportion of Caledonian-aged grains of metamorphic origin, suggesting significant sediment was recycled from Neopropterozoic metasedimentary rocks. The spatial variation in provenance indicates that, at onset of clastic input, sediment was being routed to the basin through a complex drainage system, comprising several discrete hinterland catchments, rather than supply from a single, large interconnected sedimentary system. Such complexities can only be identified with the careful application of a bespoke multi-proxy provenance approach. Supplementary material: Tables 1-5 and individual Pb-in-K feldspar plots are available at https://doi.org/10.6084/m9.figshare.c.5536691

Apatite is an accessory mineral that is widely present in most igneous and metamorphic rocks, and is a common detrital component in clastic rocks. As apatite typically incorporates U at sufficient concentrations to enable thermochronometry (e.g., U-Pb, fission track, and (U[sbnd]Th)/He), it is commonly used in detrital provenance studies. Apatite also incorporates a wide range of trace elements at concentrations readily detectable by routine laser ablation-quadrupole-inductively coupled plasma-mass spectrometry (LA-Q-ICPMS) analysis, which can also yield diagnostic provenance information (in particular Sr-Y-REE). However, detrital thermochronometry is of limited use in the case of source terrane(s) with similar crystallisation or cooling histories, while trace elements may yield non-diagnostic provenance information when their source rocks are lithologically similar (e.g., co-genetic granitoids). Here we test a complementary provenance approach which exploits F and Cl substitution into the stoichiometric Z-site in the apatite lattice. Halogen abundance in igneous apatite typically reflects the source melt composition and its subsequent differentiation history, offering potential for provenance discrimination. We apply this method to apatite from bedrock samples of five late- to post-tectonic granitoids in the Grampian and Moine terranes of the Scottish Caledonides, which yield zircon U[sbnd]Pb ages of ca. 425–398 Ma. Emplacement over this relatively short time window makes it difficult to discriminate between sediment sourced from these plutons using radiometric dating alone. Apatite F content was measured using an energy dispersive X-ray spectrometer coupled to a scanning electron microscope (SEM-EDS), while Cl and trace element (Sr-Y-REE) abundances were determined by LA-Q-ICPMS. We show that the sampled granitoids can be divided into three groups based on their apatite trace element contents and into three separate groupings based on their F and Cl abundances; all five plutons can thus be discriminated from each other using their integrated trace elements and F-Cl systematics. The granitoid groups identified by their apatite F and Cl contents correlate with those depicted by their modal mineralogy as defined in Quartz-Alkali Feldspar-Plagioclase (QAP) space, with granitoids richer in K-Feldspar (and thus more evolved) yielding apatites with higher F contents. As a pilot study, we also analysed apatite from modern river sediment in the Spey River catchment of the Grampian terrane, for which U[sbnd]Pb age data were also acquired. The Spey detrital apatites yield U[sbnd]Pb ages that are indistinguishable at the 2σ-level, but their trace element abundances allow three bedrock types to be distinguished: I-type granitoids, S-type granitoids and medium- to high-grade metamorphic rocks. The detrital apatite F and Cl data do not permit such straightforward discrimination, as apatites from S-type granitoid and metamorphic rocks have comparably low Cl contents. However, the detrital apatites with I-type granitoid affinity display significant dispersion in halogen contents (yielding the lowest F abundances with correspondingly the highest Cl contents), which identifies the presence of several more “mafic” I-type granitoid bodies in the Spey catchment. Apatite F and Cl abundances thus have potential for detailed characterisation of the individual components of granitoid suites, including delineating I-type granitoids or the presence of less evolved magmatic bodies among detrital apatites.

The Bengal Fan provides a Neogene record of Eastern and Central Himalaya exhumation. We provide the first detrital thermochronological study (apatite and rutile U-Pb, mica Ar-Ar, zircon fission track) of sediment samples collected during International Ocean Discovery Program (IODP) Expedition 354 to the mid–Bengal Fan. Our data from rutile and zircon fission-track thermochronometry show a shift in lag times over the interval 5.59–3.47 Ma. The oldest sample with a lag time of 6 m.y.) has a depositional age of 5.59–4.50 Ma, and the zircon and rutile populations then show a static peak until >12 Ma. This interval, from 5.59–4.50 Ma to >12 Ma, is most easily interpreted as recording passive erosion of the Greater Himalaya. However, single grains with lag times of

To assess provenance data and derive basin infill models with a higher level of certainty it is vital to understand how minerals used in sedimentary provenance behave in the sedimentary system. A multi-proxy approach helps ensure rigour in how provenance data are interpreted. U–Pb geochronology of refractory zircon and relatively less stable apatite, and Pb isotopic analysis of labile K-feldspar are employed in this study to reassess the provenance of Triassic sandstones in the Slyne Basin, offshore western Ireland. This approach aims at reducing the potential bias in each method, producing a complementary dataset. U–Pb zircon and apatite geochronology yields Archean–Paleoproterozoic ages, Caledonian ages and previously unrecognized Permo-Triassic ages. Pb isotopic analysis of K-feldspar does not identify the Permo-Triassic as a source. The detection of Permo-Triassic-aged detritus may suggest that volcanism was more widespread than previously recognized. These results support the hypothesis of a Triassic drainage divide between the basins offshore western Ireland and those onshore Britain and in the Irish Sea. Sand supply was dominantly from the north, with significant input from the flanks of the basin, and previously unrecorded sources, such as Permian-aged rocks, playing an important role. The provenance signal is consistent and homogenized throughout the sampled sequence indicating that the drainage system was long-lived. Supplementary material: Details of laboratory and sample preparation, data tables and summary pie charts for each sample are available at https://doi.org/10.6084/m9.figshare.c.4571096

Provenance analysis of clastic sediment is a powerful tool to track the evolution of hinterland tectonics and sediment routing systems, for which detrital U-Pb geochronology has proved a popular and rapidly-growing technique. However, >90% of published studies employ zircon (3,691/3,933 results for the keywords detrital geochronology; Clarivate Analytics Web of Science), a mineral which exhibits strong fertility bias towards felsic to intermediate igneous sources, and is rare in metamorphic settings in the absence of anatexis (e.g., Moecher & Samson, 2006). Thus, the development of complementary proxies is desirable. Garnet group minerals are particularly promising because garnet is dominantly formed in metamorphic settings and is a rock-forming mineral in several common metamorphic lithologies; it is thus typically abundant in clastic sediment sourced from orogenic terranes. Moreover, it can incorporate sufficient U to be dated in-situ by the U-Pb method (e.g., Millonig et al., 2020).Here we focus on the Oligo-Miocene pro-foreland basin of the European Alps. Evolving from a distal marine to a fluvial-alluvial environment affected by at least one major marine incursion, the basin preserves a rich record of tectonic and climatic change in the hinterland. We report detrital garnet U-Pb and trace-element data acquired by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS), which we integrate with compositional data obtained by energy- and wavelength-dispersive X-ray spectroscopy (Stutenbecker et al., 2019), and crystallographic data from Raman spectroscopy. We integrate these results with detrital apatite, rutile, and zircon U-Pb data, and discuss the implications for Alpine tectonics and drainage evolution, and future potential for detrital garnet U-Pb analysis. Millonig, L., et al., 2020. Earth Planet. Sci. Lett. 552, 116589, doi: 10.1016/j.epsl.2020.116589Moecher, D., & Samson, S., 2006, Earth Planet. Sci. Lett. 247, 252–266, doi: 10.1016/j.epsl.2006.04.035Stutenbecker, L., et al., 2019, Solid Earth 10, 1581–1595, doi: 10.5194/se-10-1581-2019

Antarctic ice-sheet instability is recorded by ice-rafted debris (IRD) in mid- to high-latitude marine sediment, especially throughout climate transitions. The middle Miocene climatic transition (MMCT), 14.2 to 13.8 Ma, which marks the end of a significant warm period during the mid-Miocene, saw a rapid cooling of ca. 6-7 °C in the high-latitude Southern Ocean. This climatic shift was also accompanied by a global δ18O excursion of ca. 1‰, indicating a time of global cooling and significant Antarctic ice expansion (Shevenell et al., 2004). The MMCT is recorded by numerous IRD-rich sediment horizons in deep-sea sediment cores around the Antarctic margin, reflecting iceberg calving during times of ice-sheet instability. Resolving the locations of iceberg calving sites by detrital provenance analysis during the MMCT will be an important tool for forecasting effects of anthropogenic climate change.Here we present results of a multi-proxy provenance study by using K- and plagioclase feldspar, selected due to their relative abundance in clastic sediment, and tendency to incorporate Rb (Kfs only), Pb, and Sr at analytically useful concentrations, thus enabling source-terrane fingerprinting. While Pb-isotope fingerprinting is an established method for provenance analysis of glaciogenic sediment (Flowerdew et al., 2012), combining in-situ Sr-isotope fingerprinting with 87Rb/87Sr dating is a novel approach. These techniques are applied to deep-sea core ODP113-694, which was recovered from the Weddell Sea; as this is located ca. 750 km from the continental rise, in 4671.3 m of water. This location is ideal, as it acts as a major iceberg graveyard making it a key IRD depocenter (Barker, Kennett et al., 1988). Within the core, several IRD layers were identified and analysed with preliminary depositional ages of 14 to 14.4 Ma.We discuss the implications of our results in terms of location of active iceberg calving sites and further consider the viability of our multi-proxy provenance approach to the Antarctic offshore.Barker, P.F., Kennett, J.P., et al., 1988, Proc. Init. Repts. (Pt. A): ODP, 113, College Station, TX (Ocean Drilling Program).Flowerdew, M.J., et al., 2012, Chemical Geology, v. 292–293, p. 88–102, doi: 10.1016/j.chemgeo.2011.11.006.Shevenell, A.E., et al., 2004, Science, v. 305, p. 1766-1770, doi: 10.1126/science.1100061.

Late Quaternary Antarctic ice-sheet instability is recorded by ice-rafted debris (IRD) in mid- to high-latitude marine sediment, especially during marine isotope stages (MIS) 2-3, but drivers of this instability remain enigmatic (Labeyrie et al., 1986). A key step in resolving this puzzle is to determine the location of iceberg calving sites, thus highlighting ice sheet sectors exhibiting repeated instability. Single-grain U-Pb provenance analysis applied to clastic IRD provides a suitable high-resolution tool for this task, and also permits discrimination of continental IRD from volcanic material. The application of multiple proxies (apatite, rutile, and zircon) is critical in order to reduce source area fertility biases: for example, the near exclusive occurrence of zircon in felsic-intermediate igneous rocks (e.g., Hietpas et al., 2010).Here, we present detrital apatite, zircon, and rutile U-Pb data from samples taken from a gravity core from the Odyssea contourite drift system, located on the margin of the Ross Sea (Rebesco et al., 2018) and deposited during MIS2-3. Contourites are marine clastic sediment deposits forming by along-slope, bottom currents reworking of fine-grained (clay-silt) sediments delivered by down-slope sedimentary processes (e.g. meltwaters, turbidity currents, debris flows). Crucially, contourite targetting eliminates the challenge of distinguishing IRD from coarse (sand-gravel) turbidite material in basin deposits, as ice-sheet instability is also associated with turbidite production at glaciated shelf margins (e.g., Bart et al., 1999).We couple our analysis with the multi-proxy sediment analyses previously performed by Lucchi et al. (2019). We consider the implications of our data for the advance and retreat of the Antarctic Ice Sheet during MIS 2-3, and discuss the further applicability of our multi-proxy approach around Antarctica.Bart, P.J, et al., 1999, Journal of Sedimentary Research, v. 69, p. 1276–1289, doi:10.2110/jsr.69.1276.Hietpas, J, et al., 2010, Geology, v. 38, p. 167–170, doi:10.1130/G30265.1.Lucchi, R.G, et al., 2019. EGU General Assembly 2019, Vienna April 7th–12th, Geophysical Research Abstracts Vol. 21, EGU2019-10409-1Rebesco, M, et al., 2018, preliminary results, in POLAR 2018 SCAR/IASC Open Science Conference, v. GG2 Arctic, p. 14133.Labeyrie, L, et al., 1986, Nature, v. 322, p. 701–706.

Detrital geochronology, generally focused on zircon only, is widely used not only to obtain qualitative information on source areas but also in quantitative provenance analysis aimed at calculating sediment yields and erosion rates under the assumption that age spectra broadly reflect the proportions of areal exposures of source rocks. The principal aim of this article is to put this assumption to test. The Tibetan Plateau and Himalayan belt, in which the age of magmatic and metamorphic events has been accurately determined through decades of geological and geochronological studies, represent an excellent natural laboratory for provenance analysis. In this study, we focus on sand carried by three major Tibetan rivers - including the largest tributaries of the Yarlung Tsangpo draining either the Lhasa block or the Himalaya exclusively - and couple classical petrographic and heavy-mineral analyses with geochronological and geochemical fingerprinting of detrital zircon, monazite, titanite, and rutile as witnesses of episodes of crustal growth in their catchment. Zircon, rutile, monazite, and titanite provide different responses to magmatic and metamorphic events and are highly to moderately durable minerals that can be preserved in ancient sandstones, thus representing precious tracers in provenance analysis. Our results show that largely euhedral zircon and titanite grains in Lhasa River sand reflect the multiple magmatic events that affected the Lhasa block through the Mesozoic and Cenozoic, and together with detrital monazite and rutile highlight post-collisional metamorphic events in the Nyainqentanglha Range. Mostly rounded detrital minerals generated in the Nianchu and Pumchu catchments are instead largely recycled from Tethys Himalayan sedimentary rocks, but young ages of monazite and titanite grains reflect the widespread Miocene thermal event associated with leucogranite intrusions both at the top of the Greater Himalayan metamorphic unit and in Northern Himalayan gneiss domes. The geochemical signature of most rutile grains in all studied samples indicates ultimate provenance from metapelites. Most important, the age spectra of different datable detrital minerals reflect poorly and in very different proportions the areal exposure of source-rock lithologies (and in the Lhasa River catchment also the areal exposure of granitoids of different age). We conclude that, although detrital geochronology does provide essential information in qualitative provenance reconstructions, the age distributions of single minerals cannot be reliably converted in terms of proportional sediment yield, and thus cannot be used to calculate sediment budgets or trace erosion rates unless fertility bias is accurately quantified and taken into due account.

U-Pb detrital zircon geochronology is a powerful and well-established tool in provenance studies. Modern analytical techniques (particularly LA-ICPMS) increasingly facilitate the rapid acquisition of large datasets. While improvements in data handling approaches have been explored in detail (e.g., more robust propagation of analytical uncertainties and inter-laboratory age reproducibility studies), there currently are no commonly established protocols for target spot location on polyphase detrital zircon grains: should the analyst ablate the zircon core, rim, or both? Here, we present two regional U-Pb detrital zircon datasets, one from the Banda Arc in Eastern Indonesia and one from the European Alps pro-foreland basin. We demonstrate that preferential ablation solely of cores or rim overgrowths results in a failure to detect age peaks, and also that generation of single-grain core-rim age pairs can permit additional characterisation of the source rock. Thus, both cores and rims should be analysed where possible, to maximise the data obtained from detrital zircon. In addition, we advocate the use of the single-analysis concordia age in visualizing and presenting U-Pb data, which is currently under-utilised in detrital provenance studies. We utilise a large (ca. 49,500 analyses) detrital zircon dataset to demonstrate that the single-analysis concordia age maximises precision throughout geological time (which removes the need to present ages derived from different isotopic ratios across an arbitrary age threshold), and obviates the necessity to separately assess discordance.

International audience; The Siwalik sedimentary rocks of the Himalayan foreland basin preserve a record of Himalayan orogenesis, paleo-drainage evolution, and erosion. This study focuses on the still poorly studied easternmost Himalaya Siwalik record located directly downstream of the Namche Barwa syntaxis. We use luminescence, palaeomagnetism, magnetostratigraphy, and apatite fission-track dating to constrain the depositional ages of three Siwalik sequences: the Sibo outcrop (Upper Siwalik sediments at ca. 200–800 ka), the Remi section (Middle and Upper Siwalik rocks at >0.8–

Apatite is a common accessory mineral in igneous, sedimentary and metamorphic rocks. It has potential as a provenance indicator in sedimentary systems, as it can host a wide variety of trace elements in its crystal structure and can yield thermochronological age information. However, the processes controlling the trace element and U-Pb systematics of metamorphic apatite remain poorly understood, and metamorphic apatite remains significantly under-represented in compositional provenance databases linking apatite trace-element chemistry to its corresponding parent rock type. We investigate the trace-element and U-Pb systematics of metamorphic apatite from a suite of 22 bedrock samples of diverse metamorphic grade and protolith type, sampled from a variety of metamorphic terranes. Metamorphic apatite from low- to medium-grade metapelites and metabasites can be easily distinguished from granitic apatite as it is significantly depleted in Th, REE, and Y. Depletion in Th and REE + Y is attributed to growth of co-genetic epidote, which is the dominant carrier phase of the REE + Y, Th, and U in all the low- to medium-grade samples mapped by laser ablation quadrupole inductively coupled plasma mass spectrometry (LA-Q-ICP-MS) and energy dispersive X-ray spectroscopy (EDS). Apatite U contents in low- to medium-grade metapelites and metabasites are more variable than the Th and REE + Y contents, but are typically low. Consequently, grains from these rock types are often undateable by the U-Pb LA-ICP-MS method and thus are underrepresented in apatite U-Pb detrital datasets, but can still be identified as low- to medium-grade metamorphic apatite by their trace-element characteristics. Low-grade metapelite apatite is difficult to distinguish from low-grade metabasite apatite, which is likely due to the growth of U-, Th-, and REE-rich epidote in both lithologies. Detrital (granitic) apatite is stable in very low-grade (e.g. pumpellyite-actinolite facies) metasedimentary samples, while neo- or re-crystallized metamorphic apatite is widespread by the upper-greenschist facies. LA-Q-ICP-MS imaging demonstrates that low REE + Y, Th, and U metamorphic apatite rims can nucleate on detrital igneous apatite precursors with high REE + Y, Th, and U. With increasing metamorphic grade, 1) relict detrital apatite is consumed, 2) the coherence of the U-Pb concordia systematics dating metamorphism improves, and 3) the degree of dispersion on metamorphic apatite multi-element plots decreases. The highest-grade metamorphic apatite samples investigated are paragneisses, some of which have locally undergone anatexis. Apatites from these samples yield well constrained TW concordia intercept ages and minor dispersion on multi-element plots (which is attributed to the absence of epidote) and closely resemble apatite from S-type granites in their trace element characteristics.

Interpreting the wealth of new data derived from the diverse suite of modern single-grain provenance approaches available to a sedimentologist requires a thorough understanding of the potential biases in the information recorded by each mineral-provenance system. This review focuses on the various possible mineral-specific biases in U-Pb accessory mineral provenance studies employing the minerals zircon, rutile, apatite, monazite and titanite, focussing on biases resulting from variations in source-rock mineralogy (fertility). Fertility is intimately linked to the mineral petrogenesis of crystalline basement sources, which is another key aspect of this review. This petrogenetic information, which often resides in the specialist petrology literature, has great relevance to fertility studies (particularly those measuring mineral content in modern river sediment using confluence and along-trunk sampling) as trace-element abundances and/or elemental ratios in many accessory minerals can be linked to specific lithologies. Other mineral-specific biases in single-grain provenance analysis considered include physical and chemical modifications both before and after deposition, while the diverse suite of modern single-grain analytical approaches also requires understanding of potential methodological and laboratory induced-biases. A series of multi-proxy provenance studies are presented where fertility bias apparently plays a significant role. In magma-poor metamorphic belts (e.g. segments of the Himalayas and Caledonides-Appalachians), it is shown that zircon growth is limited, and monazite, apatite or rutile associated with the youngest tectonomagmatic events are significantly more fertile. Such multi-proxy provenance studies will be greatly aided in the future by high-throughput, coupled U-Pb age – trace-element analyses integrated with automated heavy mineral determinations employing highly efficient sample preparation protocols.

Samples in this paper have been assigned formations based on the Geological Survey of Ireland shapefile released prior to the commencement of the study. However, the authors were not aware that, since obtaining the samples, an updated shapefile had been released. This update affects three of the four apatite samples assigned to the Lower Devonian Ballymore Formation. The location of samples Mb-1, Mb-4 and Mb-5 now places them well within the undifferentiated, Upper Devonian Slieve Mish Group. As outlined in our paper, the apatite ages were originally produced concurrently with apatite fission track analysis and were later used in our study to provide additional provenance information in support of the detrital zircon geochronological data. In the second paragraph of the discussion section we say the following: "Williams et al. (1999) obtained an age of 411 Ma for the Cooscrawn Tuff Bed in the Ballymore Formation, which is older than 22 of the 70 detrital apatites analysed in this formation". The reassignment of the three samples to the Upper Devonian Slieve Mish Group nullifies the above statement. However, our interpretation that the depositional age of the Ballymore Formation is younger than the 411 Ma age given by Williams et al. (1999) is predominantly based upon the evidence given by the six youngest detrital zircons from the formation which underlies the Ballymore Formation (i.e. the Slea Head Formation). These zircons give a concordia age of 405 ± 4 Ma. This suggests that the Ballymore Formation was more than likely deposited after 409 Ma. We do not believe that the reassignment of the three samples has any major impact on our provenance interpretations. The ∼420 Ma age of the majority of the apatites in samples Mb-1, Mb-4 and Mb-5 actually fits with the range of Palaeozoic detrital zircons in sample AK-17 which was taken from the Slieve Mish Group, thereby supporting minor input of rocks affected by end-Scandian metamorphism.