Allen P. Nutman

University of Wollongong

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

C. R. L. Friend

Oxfam

Vickie C. Bennett

Australian National University

Solomon Buckman

University of Wollongong

MÂ

Miguel Ângelo Stipp Basei

Universidade de São Paulo

D. Bridgwater

Natural History Museum Aarhus

V. R. McGregor

Iridescent

Umberto G. Cordani

Magna Graecia University

Dunyi Liu

Chinese Academy of Geological Sciences

Yusheng Wan

Changzhou University

Feiko Kalsbeek

Geological Survey of Denmark and Greenland

Cooperative Institutions

Australian National University

Chinese Academy of Geological Sciences

Instituto de Geociencias

Universidade de São Paulo

Chinese Academy of Sciences

Geological Survey of Denmark and Greenland

University of Wollongong

University of Copenhagen

Institute of Geology and Geophysics

Planetary Science Institute

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Early Proterozoic crustal provinces in the southwestern U. S. : What they represent and implications about continental reconstructions

Geological Society of America, Abstracts with Programs; (United States) (1993)

J. L. Wooden David M. Miller Katherine E. Howard E. DeWitt Karl E. Karlstrom

The Early Proterozoic basement of the southwestern US can be divided into at least 3 major crustal provinces on the basis of Pb isotopic and geochemical signatures. These are: (1) the Mojave of SE CA, southern NV, and western AZ; (2) the Yavapai of central and northern AZ, northern NM and southern CO; and (3) the Mazatzal of southern AZ., and central and southern NM. The boundary between the Yavapai and Mazatzal provinces is close to the age province boundary proposed by Silver. Crustal provinces defined by chronologic, structural, lithologic, or metamorphic criteria usually don't distinguish regions unique in crustal formation character because these criteria often represent events that affected the crust (well) after the time of its original formation or represent non-unique information (e.g., magmatism can occur at the same time in entirely different crustal provinces). In comparison, isotopic and certain geochemical data often provide unique criteria because they are related to distinct mantle sources, specific processes, or the specific time of crustal formation. New U-Pb zircon ages determined by the SHRIMP ion microprobe indicate that the Mojave province probably has a latest Archean/earliest Proterozoic basement on which sedimentary rocks containing 2.7--2.5 Ga and 2.0--1.8 Ga detrital zircon populationsmore » were deposited. The timing of plutonic events in the Mojave and Yavapai provinces is indistinguishable from 1.76--1.70 Ga. Plutonic rocks with Yavapai isotopic and geochemical signatures intruded the eastern edge ( ) of the Mojave province as early as 1.74 Ga. This suggests that the two provinces were in close proximity from 1.76 Ga and that the older Mojave province was a buttress against which juvenile Yavapai crust formed.« less

Basement

Lithology

Source

Cite

Citations (0)

Comment on "Zircon Thermometer Reveals Minimum Melting Conditions on Earliest Earth" II

Science (2006)

Allen P. Nutman

Watson and Harrison (Reports, 6 May 2005, p. 841) interpreted low temperatures (approximately 700 degrees C) for Hadean zircons as evidence of the existence of wet, minimum-melting conditions within 200 million years of solar system formation. However, high-temperature melts (approximately 900 degrees C) are zircon-undersaturated and crystallize zircon only after substantial temperature drop during fractional crystallization. Zircon thermometry cannot distinguish between low- and high-temperature Hadean igneous sources.

Hadean

Early Earth

10.1126/science.1120977

Cite

Citations (42)

Anatomy of an Early Archean gneiss complex: 3900 to 3600 Ma crustal evolution in southern West Greenland

Geology (1993)

Allen P. Nutman C. R. L. Friend Peter D. Kinny V. R. McGregor

Research Article| May 01, 1993 Anatomy of an Early Archean gneiss complex: 3900 to 3600 Ma crustal evolution in southern West Greenland Allen P. Nutman; Allen P. Nutman 1Research School of Earth Sciences, Australian National University, Canberra, A.C.T. 2601, Australia Search for other works by this author on: GSW Google Scholar Clark R. L. Friend; Clark R. L. Friend 2Department of Geology, Oxford Brookes University, Headington, Oxford OX3 OBP, England Search for other works by this author on: GSW Google Scholar Peter D. Kinny; Peter D. Kinny 3Grant Institute, University of Edinburgh, Edinburgh EH9 3JW, Scotland Search for other works by this author on: GSW Google Scholar Victor R. McGregor Victor R. McGregor 4Atammik, Maniitsoq 3912, Greenland Search for other works by this author on: GSW Google Scholar Geology (1993) 21 (5): 415–418. https://doi.org/10.1130/0091-7613(1993)021<0415:AOAEAG>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Allen P. Nutman, Clark R. L. Friend, Peter D. Kinny, Victor R. McGregor; Anatomy of an Early Archean gneiss complex: 3900 to 3600 Ma crustal evolution in southern West Greenland. Geology 1993;; 21 (5): 415–418. doi: https://doi.org/10.1130/0091-7613(1993)021<0415:AOAEAG>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The Early Archean complex of southern West Greenland consists of polyphase, tonalitic-trondhjemitic-granodioritic (TTG) and granitic Amîtsoq gneisses with inclusions of volcanic and sedimentary rocks, gabbros, and ultramafic rocks. In this complex, rocks of similar appearance and composition were found to be of different ages by U-Pb zircon dating; the Amîtsoq gneisses comprise 3870,3820-3810, 3760, 3730, 3700, and 3625 Ma TTG and 3660-3650 and 3625 Ma granites, and their inclusions belong to several supracrustal sequences with a similar spread of ages. These results show that the complex grew by episodic addition of new TTG and welding together of rocks of different ages. A possible plate-tectonics scenario is as follows: Melting of subducted mafic (oceanic) crust formed ≥3700 Ma microcontinents consisting of TTG suites with predominantly mafic inclusions. At 3650 Ma, collision between microcontinents caused crustal thickening, high-grade metamorphism, and emplacement of leucogranites. At 3625 Ma,subduction at the edge of the >3625 Ma continental mass created a new crustal addition comprising both TTG and granite, while granites were emplaced into the >3625 Ma continental mass. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Icon

10.1130/0091-7613(1993)021<0415:aoaeag>2.3.co;2

Cite

Citations (115)

Rapid maturation and stabilisation of middle Archaean continental crust: the Akia terrane, southern West Greenland

Bulletin of the Geological Society of Denmark (2000)

Adam A. Garde C. R. L. Friend Allen P. Nutman Mogens Marker

from the Akia terrane, southern West Greenland, supported by Sm-Nd isotope geochemistry, document its middle Archaean accretional history and provide new evidence about the location of its northern boundary. Zircon populations in grey gneiss and inherited zircons in granite show that magmatic accretion of new continental crust, dominated by intrusion of tonalite sheets in a convergent island arc setting, occurred between c. 3050 and 3000 Ma, around and within a c. 3220 Ma continental core. In the central part of the terrane, tonalite sheets were intercalated with older supracrustal rocks of oceanic affinity by intrusion, thrusting and folding during the Midterhøj and Smalledal deformation phases of Berthelsen (1960). Continued tonalite injection led to a thermal maximum with granulite facies conditions at c. 2980 Ma, dated by metamorphic zircons in grey gneiss. The metamorphic maximum was contemporaneous with upright, angular folds of the Pâkitsoq deformation phase. Within a few million years followed high-grade retrogression and intrusion of two large dome-shaped tonalite-granodiorite complexes, granites s.l. derived from remobilisation of grey gneiss, and post-kinematic diorite plugs. Whereas the relative chronology of these events is firmly established from field observations, zircons from the post-granulite facies intrusions all yielded statistically indistinguishable emplacement ages of c. 2975 Ma. These results show that crustal growth occurred in several short-lived events starting at c. 3220 Ma, and that final maturation and stabilisation of new, thick continental crust took place rapidly (within c. 20 Ma) at c. 2975 Ma.

Continental arc

Continental Margin

10.37570/bgsd-2000-47-01

Cite

Citations (63)

Sr and Nd isotope systematics of polymetamorphic Archean gneisses from southern West Greenland and northern Labrador

Canadian Journal of Earth Sciences (1989)

K. D. Collerson Malcolm T. McCulloch Allen P. Nutman

Sr and Nd isotopic data for middle to late Archean polymetamorphic felsic gneisses from localities in the Nuuk area, West Greenland, are compared and contrasted with new isotopic results for early Archean Amîtsoq gneisses and with data for isotopically reworked Kiyuktok gneisses from the Saglek area, Labrador. Sr isotopic data for individual suites of felsic gneisses record the time-integrated effect of variable Rb–Sr fractionation during prograde and retrograde events as well as the effect of source inhomogeneity.Contrasting petrologic and Sr–Nd isotopic characteristics are the result of differences in level of exposure, caused partially by juxtaposition of terranes of different metamorphic character by movement on ductile shear zones and post-shearing folding deformation. Sm–Nd systematics of felsic gneisses from Nordafar, Ikerasakitsup akornga, Tinissaq, and Kangimut sammisoq – Qasigianguit define a geologically meaningless ca. 3280 Ma Nd "isochron", which is the result of mixing of samples from unrelated suites and the effect of open-system behaviour. Gneisses lying on this pseudoisochron were variably affected by ca. 2800–2900 Ma prograde granulite-facies metamorphism and structurally controlled retrogression under amphibolite- to greenschist-facies conditions.The study shows that Sr–Nd isotope systematics of geologically identifiable units may be modified by open-system behaviour during prograde and retrograde metamorphism. Isotopic data from gneiss complexes metamorphosed under granulite-facies conditions may therefore yield equivocal information concerning isochron interpretation, significance of model ages, and estimates of crustal residence time.

Felsic

10.1139/e89-039

Cite

Citations (43)

Age and Provenance of the Nindam Formation, Ladakh, NW Himalaya: Evolution of the Intraoceanic Dras Arc Before Collision With India

Tectonics (2019)

Jessica Walsh Solomon Buckman Allen P. Nutman Renjie Zhou

Abstract The Dras Arc in NW India Himalaya is a belt of basaltic‐andesites intercalated with arkose‐dominated volcaniclastic rocks of the Nindam Formation situated along the Indus Suture between India and Eurasia. Debates exist as to whether these rocks developed in a forearc basin to the Eurasian margin or as part of an intraoceanic island arc system that collided with either India or Eurasia before final continental collision. Detrital zircons from the Nindam Formation yield U‐Pb age spectra with dominant youngest age populations of ~84–125 Ma, corresponding with arc magmatism. Sandstone provenance analysis from the Nindam Formation indicates that the Dras Arc evolved from an undissected arc to dissected arc over a period of ~41 Myr. Slightly older, smaller populations occur at ~135–185 Ma, corresponding with reported ages of Neotethyan ophiolites (e.g., Spongtang). The basal section of the Nindam Formation reveals the presence of arc‐derived basaltic‐andesite and tonalite clasts, plus ophiolitic components sourced from an adjacent accretionary complex. There is a distinct absence of quartz or felsic granitic clasts, suggesting that the Nindam Formation did not develop as a forearc basin to the Ladakh Batholith of southern Eurasia but rather as separate intraoceanic island arc. A distinct “Gondwanan” signature occurs in all samples, with zircon age peaks at ~514–988, ~1000–1588, ~1627–2444, and ~2500 Ma. We suggest that the Dras and Spong arcs are the same intraoceanic island arc system that developed as a result of subduction initiation along NNE‐SSW transform faults perpendicular to the Indian and Eurasia continents.

Forearc

Island arc

10.1029/2019tc005494

Cite

Citations (28)

A new fragment of the early earth crust: the Aasivik terrane of West Greenland

Precambrian Research (2001)

Minik T. Rosing Allen P. Nutman Linea Løfqvist

10.1016/s0301-9268(00)00107-8

Cite

Citations (42)

Detrital zircon sedimentary provenance ages for the Eoarchaean Isua supracrustal belt southern West Greenland: Juxtaposition of an imbricated ca. 3700Ma juvenile arc against an older complex with 3920–3760Ma components