International Geological Correlation Programme Research Articles

Alkali fusion co-precipitation/cation exchange/extraction enrichment for determination of trace rare earth elements in rocks by inductively coupled plasma mass spectrometry

In this paper, three separation and pre-enrichment methods of Mg(OH)2 and Fe(OH)3 co-precipitation, cation exchange and 1-phenyl-3-methyl-4-benzoyl-pyrazolone (PMBP) extraction were established by sodium peroxide alkali fusion digestion. Ca, Na and K, etc. were virtually eliminated from the analysis solutions using three sample processing procedures, thereby avoiding potential matrix interference and mass spectrometry interference due to high salt content. The detection limits of three methods were 0.0009-0.0076 mg/kg，0.0011-0.0062 mg/kg，0.0023-0.0114 mg/kg, respectively；the relative deviations of the determined rare earth elements (REEs) were -6.9-7.6%, -9.1-6.6% and -8.4-12.3%，respectively. The %RSD values of the three methods were lower than 10%, demonstrating good precision. The fit for purpose of the results was also evaluated by the quality criteria test proposed by the International Geological Correlation Programme (IGCP), from which it can be deduced that the three methods were adequate considering geochemical mapping application. The three sample processing procedures can be applied for the determination of rare earth elements in rocks.

Spectral characteristics of talc and mineral abundance mapping in the Jahazpur Belt of Rajasthan, India using AVIRIS-NG data

ABSTRACT Spaceborne data with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Short Wave Infrared (SWIR) bands have been used worldwide in discriminating different clay minerals. However, due to wide bandwidth of ASTER sensors, it is difficult to distinguish between pure and impure variety of talc mineral. The present study highlights the efficacy of airborne hyperspectral data Airborne Visible/Infrared Imaging Spectrometer – Next Generation (AVIRIS-NG) for spectral analysis in talc mineral in the Jahazpur Belt of Bhilwara district in Rajasthan, India. Due to its better spectral and spatial resolution, AVIRIS-NG is found to be extremely useful in identifying talc mineral in SWIR region. Talc is characterized by doublet shaped spectral pattern in AVIRIS-NG image with strong absorption dips at 2289.75 nm and 2314.80 nm which could not be picked up in ASTER image. Spectral matching of talc pixels is verified with the field spectra of samples and available spectral library of United States Geological Survey, Jet Propulsion Laboratory, and International Geological Correlation Programme. Variation in reflectance percentage of different talc pixels is attributed to variation in chemical composition of talc. However, a large number of mixed pixels with spectral pattern of both talc and kaolinite minerals have been identified in AVIRIS-NG image which are found to be an impure variety of talc. Whole-pixel to sub-pixel classification techniques with Spectral Angle Mapper, Spectral Feature Fitting, Mixture Tuned Matched Filtering, and Linear Spectral Unmixing (LSU) techniques have been applied for talc abundance mapping in Jahazpur area. LSU is found to be the most useful and accurate technique in classifying spectrally pure to impure variety of talc.

Determination of sulfur in Soils and Stream Sediments by Wavelength Dispersive X-ray Fluorescence Spectrometry

A simple, rapid and nondestructive wavelength dispersive X-ray fluorescence spectrometry (WD-XRF) was developed for the determination of sulfur in soils and stream sediments. WD-XRF was used to study the spectral line shifts and matrix effects of different inorganic species such as sulfide, elemental sulfur, thiosulfate, sulfite and sulfate. Analysis of the spectral lines in the S Kα wavelength range confirmed that Mo Lα (2θ = 111.799 °) lines interfered with S Kα (2θ=110.683°) lines. Twenty-seven soils and stream sediments reference samples were used to calibrate and evaluate the analytical method and the detection limit for sulfur was 5.43 mg/kg. The relative error (%RE) of the reference samples was −8.3–6.4%, showing good accuracy. However, the single form of sulfur (sulfide, sulfite and sulfate) had a significant matrix enhancement effect in the sodium carbonate matrix, especially for sulfides, and its relative error was 11.9 ~ 26.9%. The results of WD-XRF, inductively coupled plasma emission spectroscopy (ICP-OES) and elemental infrared analyzer were compared. The fitness for purpose of the results was also evaluated by the quality criteria test proposed by the International Geological Correlation Programme (IGCP), from which it can be deduced that the method was adequate considering geochemical mapping application.

INTIMATE (Integration of Ice-core, Marine and Terrestrial Records) 20 Years on: Retrospect and Prospect

The INTIMATE (Integration of ice-core, marine and terrestrial records) project, the successor to the North Atlantic Seaboard Programme of International Geological Correlation Programme (IGCP-253) ‘Termination of the Pleistocene’, began in 1995 with the aim of integrating proxy climate records from around the North Atlantic during the Last Termination (18–8 ka BP). The INTIMATE remit has since expanded geographically to include the entire Atlantic basin and Australasia, while an extended temporal framework now covers the early Holocene and the Last Glacial cycle. This short paper outlines the principal achievements of the INTIMATE research community, which include the development of an event stratigraphy for the North Atlantic region; the establishment of protocols for ice–land–ocean correlation; important contributions to geochronology, most notably to tephrochronology, and to palaeoenvironmental and palaeoclimatic reconstructions; and the designation of the Greenland ice-core record as the global stratotype for the Pleistocene–Holocene boundary. Future directions of the INTIMATE programme are also briefly considered.

The 25th International Geological Congress, Sydney, Australia (1976)

s. For similar reasons the sessions dealing with Recent Advances in Exploration Geophysics attracted more than 70 papers. The rare interaction of Soviet and Australian geologists in these economic geology sessions would have been most interesting. Significant numbers of presentations concerned plate tectonics, which had gained acceptance over the previous decade. Precambrian geology and deep sea drilling also generated much interest and attracted numerous contributions. The largest audiences, approaching 300, were observed in sessions dealing with Circum–Pacific plutonism, exploration geophysics, uranium geology, mineral deposits, tectonics and Precambrian geology. Notably the Sydney IGC was the first following the formal establishment of the International Geological Correlation Programme (IGCP) in early 1973. Over the previous decade Australia had contributed significantly to this development (Harrington, 1994). Specialist Congress symposia sponsored by IGCP projects concerned: — Earliest Archaean tectonics and magmatism — Circum-Pacific plutonism — Tectonic aspects of ophiolites — Global correlation of epochs of folding — Correlation of kaolin genesis and age — Precambrian / Cambrian boundary problem

Chapter 1 An overview of the continental shelves of the world

This Memoir explores the variability and controlling processes of sedimentation, morphology and tectonics on the world's continental shelves, with emphasis on their evolution during the last glacio-eustatic cycle. This work builds on some earlier volumes on continental shelves, notably those by Trumbul et al. (1958), Boillot (1978), De Batist & Jacobs (1996), Nittrouer et al. (2007) and Li et al. (2012) among others, although there has not been a previous comprehensive global-scale synthesis. The subject material presented here was developed in several International Geoscience Programmes (formerly the International Geological Correlation Programme, IGCP) concerned with shelves. Project 396 ‘Continental Shelves in the Quaternary’ (1996–2000) was followed by IGCP 464 ‘Continental Shelves during the Last Glacial Cycle: Knowledge and Applications’ (2001–2007) and finally by IGCP 526 ‘Risks, Resources and Record of the Past on the Continental Shelf’ (2007–2011). In this Memoir, 23 papers are devoted to the description of different aspects of shelves from all seven continents and which are representative of the world's shelves. However, there remain significant gaps in our compilation. A glance at Figure 1.1 indicates the sparse coverage of data, particularly using modern techniques of investigation, for Africa, Russia and the Polar regions. However, new data are presented from some frontier provinces, such as Myanmar, Morocco and Ecuador. Fig. 1.1. The location of the shelf areas presented in this volume. Base map from Smith, W. H. F. & Sandwell, D. T. 1997. Global sea floor topography from satellite altimetry and ship depth soundings. Science , 277 , 1956–1962. Reprinted with permission from AAAS. The continental shelf is the part of the seafloor most used by society. Although shelf areas account for little more than 8% of the marine areas of the world, they are the part of the sea most used for navigation, recreation, fishing and …

Chapter 1 Early Palaeozoic biogeography and palaeogeography: towards a modern synthesis

The benchmark volume edited by Christopher Scotese & Stuart McKerrow (1990), the so-called ‘Green Book’, marked a turning point in Palaeozoic biogeography and geography. The 40 papers in that volume included substantial new data and important syntheses on palaeoclimatology, palaeomagnetism and the distribution of climatically sensitive sediments, but the majority of contributions were on Palaeozoic biogeography. Since 1990 there have been major advances in the taxonomy of Early Palaeozoic organisms, the correlation of Lower Palaeozoic rocks together with numerical methods for the analysis of fossils and their distributions. Moreover and most significantly there has been a quantum leap in the accuracy and precision of palaeogeographic reconstructions, reconciling in many cases palaeomagnetic data and the distribution of fossil organisms. The Early or (Lower) Palaeozoic was an interval characterized by a major radiation of marine life, including not only the ‘Cambrian Explosion’, but also the ‘Great Ordovician Biodiversification’. An International Geoscience Programme (formerly International Geological Correlation Programme, IGCP) was dedicated to the Great Ordovician Biodiversification Event (IGCP 410, 1997–2002). This programme focused on the Ordovician, but it also analysed the roots of the Ordovician biodiversification in the Cambrian, the first big mass extinction at the end of the Ordovician, and the Silurian recovery. A subsequent programme, the IGCP 503, ‘Ordovician Palaeogeography and Palaeoclimate’, followed from 2004 to 2009. Several special issues and review papers resulted from this programme, including special issues on Lower Palaeozoic palaeoenvironments (Servais & Owen 2010) and Lower Palaeozoic sea-level and climate (Munnecke et al. 2010). The papers presented here originated from the ‘Absolutely Final Meeting of IGCP 503: Ordovician Palaeogeography and Palaeoclimate’ in Copenhagen, September, 2009 (see Harper et al. 2011). That symposium focused especially on the palaeogeographical dimension of the Cambrian–Ordovician marine radiation; the current volume critically uses the available world pre-drift maps for the …

Sea-level rise and coastal change: the past as a guide to the future

There is a broader awareness than ever that we live in a changing environment. The spectre of climate change is of wide concern, and the observed trends and anticipated consequences of an acceleration of sea-level rise pose a series of threats for the future of people who live in coastal communities. Coastal geoscientists are able to reconstruct the position of former sea levels; they can also explain much of the geographical variation in relative sea-level history. Successive collaborative projects (many under the auspices of international programmes sponsored by IGCP and INQUA) derived local sea-level histories and compiled atlases of relative sea-level curves, and some addressed past coastal behaviour in response to these changes. The most recent International Geological Correlation programme project 588, ‘Preparing for coastal change’, continues this impressive lineage of projects that have laid the foundations for our understanding of sea-level behaviour over the late Quaternary. Today, these issues are a major focus in the debate about climate change, its impacts, and the need for adaptation on the most vulnerable shorelines. There is clearly a role for the palaeoenvironmental skillset honed through successive geoscientific projects. Investigations of past coastal environments have provided the tools for delineating past levels of the sea, but the stratigraphical and geochronological studies which were necessary to reconstruct the sea-level position also provide insights into where the shoreline lay and how the coast behaved as sea level changed. If the present is the key to the past, then the past, seen from the context of the present, can be a guide to the future. Collaborative projects and international co-operation between scientists from different disciplines can play important roles in future debates about how our world will change. First, the lessons learnt about the patterns of variation of relative sea level need to be more widely recognised by climate scientists. Efforts aimed at establishing the rate of future global sea-level rise need to be complemented by protocols to determine regional deviations from that mean rate of sea-level change. Second, modes of coastal change need to be identified to replace simplistic heuristics of coastal response, such as the Bruun rule. Simulation modelling offers a suite of tools that appear to give coastal managers guidance, but geoscientists should strive to produce evidence that can be used to develop and validate model behaviour. Coastal scientists presently have a relatively good understanding of coastal behaviour at millennial timescales, and process operation at contemporary timescales. However, there is less certainty about how coasts change on decadal to century timescales. It is these latter timescales which are particularly important for managers and policy-makers. These, and related challenges, provide a focus for research that will have a relevance for society that the coastal geoscience research community has rarely experienced.

Tectonic significance of Late Ordovician silicic magmatism, Avalon terrane, northern Antigonish Highlands, Nova Scotia 1 This article is one of a series of papers published in CJES Special Issue: In honour of Ward Neale on the theme of Appalachian and Grenvillian geology.2 Contribution to International Geological Correlation Programme (IGCP) Project 497.

Avalonia was a microcontinent during most of the Ordovician, separating the Iapetus Ocean to the north from the Rheic Ocean to the south. In the northern Antigonish Highlands, Nova Scotia, volcanic rocks (Dunn Point and McGillivray Brook formations) underlie Early Silurian – Early Devonian strata (Arisaig Group) and were thought to represent extension that heralded the development of the basin into which Arisaig Group strata were deposited. However, recent U–Pb (zircon, thermal ionization mass spectrometry) data from rhyolite in the Dunn Point Formation (DPF) yielded an age of 460.0 ± 3.4 Ma, and, here, we report a concordant age of 454.5 ± 0.7 Ma for an ignimbrite in the overlying McGillivray Brook Formation (MBF). These data confirm a ca. 10 million year gap between volcanism and onset of Arisaig Group deposition, which occurred after accretion of Avalonia to Baltica. The DPF and MBF both resemble A-type SiO2-rich magmas. The MBF has very high concentrations of Zr (745–1965 ppm), Y (65–213 ppm), Nb (57 to 185 ppm), and high Ga/Al. Several MBF samples exhibit strong LREE depletion, consistent with fractionation of LREE-bearing accessory phases. εNdt values for MBF (t = 455 Ma) range from +1.5 to +3.9, and overlap with DPF rhyolites that range from +2.9 to +3.7. Depleted mantle model ages for MBF and DPF samples unaffected by accessory phase fractionation are between 0.9 and 1.2 Ga and are similar to TDM values in older (Neoproterozoic, Cambrian) crustally derived felsic rocks, suggesting derivation from the lower crustal basement beneath the Antigonish Highlands. DPF and MBF rocks were probably erupted in a local extensional environment within an ensialic arc, perhaps analogous to the modern Taupo Volcanic Zone in northern New Zealand.

Outlines of New Global Geochemical Mapping Program

Abstract:Since 1988, great efforts and enthusiasm had been paid by applied geochemists in the implementation of global geochemical mapping through the International Geological Correlation Program's Projects 259 and 360, and the Task Group on ‘Global Geochemical Baselines’ established by the International Union of Geological Sciences (IUGS), in collaboration with the International Association of Geochemistry (IAGC). But how to use extremely low‐density sampling to obtain a global picture of the distribution of most elements in the periodic table in a reasonably short time is still a great challenge faced by the applied geochemistry community. It will depend on the continuous development of new mapping concept, and the advisable and courageous innovation of methodology for searching other suitable sample media and sampling layout. Based on the encouragement results obtained from the representativeness study of delta sediments conducted at the mouth of Yangtze River, and at the mouths of its four major tributary, it is expected to broadly apply the geochemical fractal self‐similarity nature to main rivers and their estuaries with catchments up to hundreds of thousands or over a million square kilometers in the world. With this new mapping concept, a new outlines of a Global Geochemical Mapping Program was advanced and the establishment of an International Research Center of Global Geochemical Mapping was also suggested to facilitate the programs implementations.

Breaking boundaries: IGCP 521 database and science informatics

Over the past decade, the Internet has greatly accelerated collaboration among scientists: realizing the full potential of the sharing and repurposing of research data is now viewed as a priority. In order to grasp the “big picture” of events in the Black Sea–Mediterranean Corridor over the past 30,000 years, an experimental Web-database application has been designed for the International Geological Correlation Programme (IGCP) Project 521 that will share data from scientists worldwide. All data entered must be accompanied by GIS coordinates, depth/elevation, age (historical, geological, or archaeological) and metadata related to the environmental context. In this way, when plotted by latitude and longitude on general topographic and bathymetric maps of the Corridor with NASA land imagery, data from various disciplines and research endeavors can be combined, consolidated and visualized. Each point on the Web-based map presentation is “clickable” to reveal the source, metadata and links to further information. A prototype system demonstrates the potential to display all available data sets in millennial to decadal time slices, and to create displays and juxtapositions of data sets that have rarely or never co-existed before because of political, linguistic, and disciplinary boundaries. Such displays reveal new perspectives of old interpretations by breaking the restrictive boundaries of disciplinary research domains. The IGCP 521 project currently brings together researchers from twenty-three nations, allowing them to share data at annual meetings from 2005 to 2010. To prevent disintegration of this multi-national liaison at the end of the project, however, there is an urgent need to encourage database entry both during and beyond the IGCP 521 lifespan, so that the informatics system persists as a living archive.

Assembly and Breakup of Rodinia (Some results of IGCP project 440)

The principal results of project 440 “Assembly and Breakup of Rodinia” of the International Geological Correlation Programme (IGCP) are reviewed in this work. A map of that supercontinent compiled using geological and paleomagnetic data describes global paleogeography 900 Ma ago. The assembly of Rodinia, which comprised most of Precambrian continental blocks, lasted ca. 400 m.y. (from 1300 to 900 Ma). Its breakup presumably triggered by mantle superplume took place between 830 and 650 Ma. The correlation between tectonic events in different continental blocks is considered. Some problems concerning the Rodinia reconstruction and history, e.g., the slow growth of juvenile crust and effects of mantle-plume events during the amalgamation period and of glaciations at the breakup time, are discussed. The latter caused changes in the biosphere and climate, whereas postglacial periods stimulated progress in biota evolution.

Thematic Section: Geological anatomy of East and South Asia: Paleogeography and paleoenvironments in Eastern Tethys (IGCP 516) Part 1

Thematic Section: Geological anatomy of East and South Asia: Paleogeography and paleoenvironments in Eastern Tethys (IGCP 516) Part 1

From geochemical prospecting to international geochemical mapping: a historical overview

This paper provides a history of the development of regional geochemical mapping. Modern geochemistry was born in the Soviet Union in the 1930s, and the basic methodologies for regional mapping had been developed by the late 1960s, with important extensions being made in the 1980s. The paper records the development of regional geochemical surveys, or mapping, in the context of spatial scale and transition from a mineral exploration and resource assessment tool to an environmental mapping exercise supporting multi-disciplinary research. Attention is drawn to the role of the International Geological Correlation Program's Projects 259 and 360, and the continuing role of the International Union of Geological Sciences, in providing an international focus and dimension to global geochemical mapping. The paper closes with a section on some of the current research issues, opportunities and challenges for regional geochemical mapping.

A Special Issue Devoted to Continental Margin Massive Sulfide Deposits and Their Geodynamic Environments

The papers in this issue arise from a special session held at the May, 2003 Geological Association of Canada (GAC)-Mineralogical Association of Canada (MAC)-Society of Economic Geologists (SEG) meeting in Vancouver, British Columbia, Canada, entitled “Massive Sulfides on the Edge: The Formation of VMS and SEDEX Deposits Within Evolving Continental Margins.” Continental margin environments (e.g., continental arcs, arc rifts, and back-arc basins) host some of the world’s largest volcanogenic massive sulfide (VMS) and sedimentary-exhalative (SEDEX) deposits (e.g., Bathurst, Iberian Pyrite Belt), yet there remains an incomplete understanding of the regional- to local-scale controls on their setting and genesis. The purpose of this issue is to explore and better understand the setting, styles, and continent- to deposit-scale controls on the localization of these deposits within and along continental margins. The papers here build on recent multidisciplinary projects such as those on the Bathurst camp (Goodfellow et al., 2003), on Australian VMS environments (Large et al., 2001), and the ongoing International Geological Correlation Program (IGCP) Project 502 on “Global Comparison of Volcanic-Hosted Massive Sulfide Districts: The controls on the distribution and timing of VMS deposits” (Allen et al., 2002). The results presented here contribute new data and observations from both well-known camps (e.g., Iberian Pyrite Belt) and new camps and deposits for which little published information is available (e.g., Finlayson Lake in the Yukon-Tanana terrane, Greens Creek in the Alexander terrane, Baiyinchang in Gansu Province, China, La Plata in western Ecuador, and Cuale in the Gurrerro terrane, Mexico). The papers in the volume range from those that are regional in scope (e.g., Bissig et al., 2008; Mortensen et al., 2008; Taylor et al., 2008), to new deposit descriptions (e.g., Bradshaw et al., 2008; Chiaradia et al., 2008), to new information on known deposits (e.g., Barrett et al., 2008; …

Essentials of medical geology: impacts of the natural environment on public health

Essentials of medical geology: impacts of the natural environment on public health

WEBBY, B. D., PARIS, F., DROSER, M. L. & PERCIVAL, I. G. 2004. The Great Ordovician Biodiversification Event. xi+484 pp. New York: Columbia University Press. Price US $99.50, £69.00 (hard covers). ISBN 0 231 12678 6

WEBBY, B. D., PARIS, F., DROSER, M. L. & PERCIVAL, I. G. 2004. The Great Ordovician Biodiversification Event. xi+484 pp. New York: Columbia University Press. Price US $99.50, £69.00 (hard covers). ISBN 0 231 12678 6 - Volume 142 Issue 2

Not "Just A Petrographer": The Life and Work of Felix Chayes (1916-1993)

Felix Chayes's life and career, largely spent at the Geophysical Laboratory of the Carnegie Institution, Washington, DC, are described. His principal motivation was to improve the reliability of geological interpretation and decision-making through the use of quantitative techniques and the application of statistical methods: e.g., as discussed in his monograph Petrographic Modal Analysis (1956b). He attempted to raise the awareness of the geological community concerning the inherent problems connected with the interpretation of percentaged- and ratio-data, in both petrography and geochemistry, and to develop approaches to their solution (as discussed in his monograph Ratio Correlation, 1971a), although these were never wholly successful. From the mid-1960s onwards, he was deeply involved in the development and application of geochemical databases for igneous petrology (International Geological Correlation Programme—1GCP—Projects 163 and 239). From 1984 he was Chair of the International Union of Geological Sciences (IUGS) Subcommission on Electronic Databases for Petrology. Emphasis is placed on Chayes's early research as this established the motivation for his statistical approach to petrology.

Professor Salvador Reguant and his work on the International Geological Correlation Programme (IGCP)

At the beginning of the 1970s the International Union of Geological Sciences (IUGS) was founded and one of its first projects was the establishment of an agreement with UNESCO for the creation of the International Geological Correlation Programme (IGCP), an agreement that was signed in 1972. The programme covers a broad range of areas of work within Earth Sciences, from the strictly geological to more applied areas of knowledge; from this comes the informal name given, on occasions, to this programme – that of ‘Geo-sciences at the service of society’. In line with the international nature of the IGCP, the projects adopted must reflect a regional interest, globally speaking, in both the area covered and the composition of the research teams. Both the pressure on natural resources and the effects of natural disasters have produced a tendency to redirect some aspects of the work of the IGCP towards a more intelligent use of our planet.

Global correlation of long Quaternary fluvial sequences: a review of baseline knowledge and possible methods and criteria for establishing a database

AbstractFluvial sequences, particularly major terrace staircases, represent potential archives of palaeoclimatic fluctuation during the Quaternary. Such sequences can span much if not all of the Quaternary and, provided that dating is possible, can serve as stratigraphical frameworks for correlation with evidence from other depositional environments. In particular, they can provide a terrestrial lithostratigraphical framework that can be correlated with the global marine oxygen isotope record. Fluvial lithos-tratigraphical frameworks also provide important contexts for records of faunal evolution and human occupation, the latter largely determined from the occurrence of artefacts in fluviatile sediments.This paper announces a new project within the International Geological Correlation Programme, devoted to fluvial sequences (IGCP 449 ‘Global Correlation of Late Cenozoic fluvial deposits’). It attempts to summarize existing baseline knowledge at the outset of the project and outlines the proposed methods and criteria for establishing a database of fluvial sequences.