Foreword to the special issue: Arctic Palaeoclimate and Its Extremes (APEX)     

Martin Jakobsson  Robert F. Spielhagen  Jörn Thiede  Claus Andreasen  Brenda Hall  Ólafur Ingólfsson  Kurt H. Kjær  Thijs van Kolfschoten  Gerhard Krinner  Antony Long  Juha-Pekka Lunkka  Dmitry Subetto  & John Inge Svendsen 《Polar research》2008,27(2):97-104

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Ore Group Classification - A Case Study from Ingaldhal Sulphide Deposit, Karnataka Craton, India     

Joju P. Antony   《Gondwana Research》1999,2(1):67

All varieties of base metal sulphide deposits may be classified using base metal ratios viz. Copper Ratio (CR=100Cu/{Cu+Zn}), Zinc Ratio (ZR=100Zn/{Zn+Pb}) and Lead Ratio (PR=100Pb/{Pb+Cu}). Based on this ore group classification an attempt has been made to identify ore groups present in the late Archaean volcanic associated Ingaldhal Sulphide Deposit (ISD) of Karnataka Craton. Using base metal ratios (CR, ZR and PR) five distinct fields are suggested: Cu, Cu-Zn, Cu-Zn-Pb, Zn-Cu and Zn-Cu-Pb/Zn-Pb-Cu with their associated geological and geochemical characteristics. A transitional change in the ore groups is observed from the North Block (Cu rich groups; CR>50) to South Block (Zn and Pb dominated groups; CR<50) and the Main Block is represented by all the five ore groups.This classification may be useful as a pointer in the exploration of polymetallic base metal deposits. Copper rich groups (Cu, Cu-Zn and Cu-Zn-Pb) exhibit high concentration of Bi and Co, and low CaO and Cd whereas the Zn rich groups (Zn-Cu and Zn-Cu-Pb/Zn-Pb-Cu) show high CaO and Cd, and low Bi and Co. The CR of most of the ore groups exhibit a sympathetic relation with Co and Ag. A preliminary attempt has been made for better understanding of ore group genesis of ISD by integrating ore group characteristics with deduced geothermometry.  相似文献   

Observations of bedforms on a dissipative macrotidal beach     

Jon Miles  Antony Thorpe  Paul Russell  Gerd Masselink 《Ocean Dynamics》2014,64(2):225-239

Field measurements of wave ripples and megaripples were made with a Sand Ripple Profiler in the surf and shoaling zones of a sandy macrotidal dissipative beach at Perranporth, UK in depths 1–6 m and significant wave heights up to 2.2 m. A frequency domain partitioning approach allowed quantification of height (η), length (λ) and migration rate of ripples and megaripples. Wave ripples with heights up to 2 cm and wavelengths ～20 cm developed in low orbital velocity conditions (u _m?<?0.65 m/s) with mobility number ψ?<?25. Wave ripple heights decreased with increasing orbital velocity and were flattened when mean currents were >0.1 m/s. Wave ripples were superimposed on top of megaripples (η?=?10 cm, λ?=?1 m) and contributed up to 35 % of the total bed roughness. Large megaripples with heights up to 30 cm and lengths 1–1.8 m developed when the orbital velocity was 0.5–0.8 m/s, corresponding to mobility numbers 25–50. Megaripple heights and wavelengths increased with orbital velocity but reduced when mean current strengths were >0.15 m/s. Wave ripple and megaripple migrations were generally onshore directed in the shoaling and surf zones. Onshore ripple migration rates increased with onshore-directed (+ve) incident wave skewness. The onshore migration rate reduced as offshore-directed mean flows (undertow) increased in strength and reached zero when the offshore-directed mean flow was >0.15 m/s. The migration pattern was therefore linked to cross-shore position relative to the surf zone, controlled by competition between onshore-directed velocity skewness and offshore-directed mean flow.  相似文献   

Late Devensian and Holocene relative sealevel changes at Loch nan Eala,near Arisaig,northwest Scotland     

Ian Shennan  James B. Innes  Antony J. Long  Yongqiang Zong 《第四纪科学杂志》1994,9(3):261-283

Pollen, diatom, radiocarbon and lithostratigraphical data from isolation basins in northwest Scotland are used to quantify the reference water (tide) level, indicative range and age of differenty types of isolation and connection contacts. Tendencies of sea-level movement and relative sea-level changes from the mid-Lateglacial Interstadial (11.8 ka BP) to the late Holocene are constructed from these data. Relative sea-level fell continuously from + 17.8 m OD at 11.8 ka BP to ca. + 5.2 m OD at 10.1 ka BP. From an unkown minimum between 10 ka and 9 ka BP relative sea-level then rose to +6.3 m OD at 8.3 ka BP. The maximum Holocene sea-level occurred within the range +6.6 m OD to +9.3 m OD between 6.6 ka BP and 4.0 ka BP before falling to present. Isobase, age-altitude and quantitative rebound models for northwest Scotland are tested using these sealevel data, but none of the published models shows close agreement with the new results.  相似文献   

Lateglacial and Holocene relative sea‐level changes and first evidence for the Storegga tsunami in Sutherland,Scotland          下载免费PDF全文

Antony J. Long  Natasha L. M. Barlow  Sue Dawson  Jon Hill  James B. Innes  Catherine Kelham  Fraser D. Milne  Alastair Dawson 《第四纪科学杂志》2016,31(3):239-255

We reconstruct one of the longest relative sea‐level (RSL) records in north‐west Europe from the north coast of mainland Scotland, using data collected from three sites in Loch Eriboll (Sutherland) that we combine with other studies from the region. Following deglaciation, RSL fell from a Lateglacial highstand of +6?8 m OD (Ordnance Datum = ca. mean sea level) at ca. 15 k cal a BP to below present, then rose to an early Holocene highstand and remained at ca. +1 m OD between ca. 7 and 3 k cal a BP, before falling to present. We find no evidence for significant differential Holocene glacio‐isostatic adjustment between sites on the north‐west (Lochinver, Loch Laxford), north (Loch Eriboll) and north‐east (Wick) coast of mainland Scotland. This suggests that the region was rapidly deglaciated and there was little difference in ice loads across the region. From one site at the head of Loch Eriboll we report the most westerly sedimentary evidence for the early Holocene Storegga tsunami on the Scottish mainland. The presence of the Storegga tsunami in Loch Eriboll is predicted by a tsunami wave model, which suggests that the tsunami impacted the entire north coast of Scotland and probably also the Atlantic coastline of north‐west Scotland.

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Did the Kyrenia Range of northern Cyprus rotate with the Troodos–Hatay microplate during the tectonic evolution of the eastern Mediterranean?     

Antony Morris  Alastair H. F. Robertson  Mark W. Anderson  Emma Hodgson 《International Journal of Earth Sciences》2016,105(1):399-415

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Editorial     

Antony Long 《第四纪科学杂志》2010,25(2):95-95

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Reply: Postglacial relative sea‐level observations from Ireland and their role in glacial rebound modelling     

Robin Edwards  Antony Brooks  Ian Shennan  Glenn Milne  Sarah Bradley 《第四纪科学杂志》2008,23(8):821-825

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Direct evidence of fluid mixing in the formation of stratabound Pb–Zn–Ba–F mineralisation in the Alston Block, North Pennine Orefield (England)     

Jon E. Bouch  Jonathan Naden  Thomas J. Shepherd  John A. McKervey  Brian Young  Antony J. Benham  Hilary J. Sloane 《Mineralium Deposita》2006,41(8):821-835

The North Pennine Orefield Alston Block has produced approximately 4 Mt Pb, 0.3 Mt Zn, 2.1 Mt fluorite, 1.5 Mt barite, 1 Mt witherite, plus a substantial amount of iron ore and copper ore from predominantly vein-hosted mineralisation in Carboniferous limestones. However, a significant proportion of this production (ca. 20%) came from stratabound deposits. Though much is known about the vein mineralisation, the relationship between the veins and the stratabound mineralisation is not well-understood. New petrographic, isotopic and fluid inclusion data derived from samples of stratabound mineralisation allow us to present a unified model that addresses the genesis of both the vein and stratabound styles of mineralisation. The mineralisation can be considered in terms of three episodes:

1.	Dolomitisation and ankeritisation Limestones in the vicinity of the stratabound mineralisation were pervasively dolomitised/ankeritised, and developed vuggy porosity in the presence of a high-salinity brine consistent with fluids derived from adjacent mud and shale-filled basins.
2.	Main stage fluorite–quartz–sulphide mineralisation Metasomatism of limestone was accompanied by brecciation, dissolution and hydrothermal karstification with modification of the existing pore system. The open space was filled with fluorite, galena, sphalerite, quartz and barite, formed in response to mixing of low-salinity sodic groundwater with high-salinity calcic brine with elevated metal contents (particularly Fe up to 7,000 ppm) relative to “normal” high total dissolved solids sedimentary brines.
3.	Late-stage barite mineralisation paragenetically appears to represent either the waning stages or the distal portions of the main hydrothermal circulation system under cooler conditions.

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Turbulence from localized random expansion waves     

Antony J. Mee  Axel Brandenburg 《Monthly notices of the Royal Astronomical Society》2006,370(1):415-419

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