Tesis: "Greenland evolution"

1

White, Arthur Percy 1972. "Extensional evolution of the central East Greenland Caledonides". Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8233.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2001.
CDROM contains entire thesis in PDF format.
CDROM copy of thesis held by MIT Institute Archives only.
Includes bibliographical references.
This thesis addresses the complexity of both syn- and post-orogenic extension in the overriding plate during Caledonian continental collision through field and laboratory investigations in the central East Greenland Caledonides. During the course of this work, attempts were made to answer some of the outstanding regional and local questions in East Greenland geology. Structural, U-Pb and ⁴⁰Ar/³⁹Ar geochronologic, petrographic and thermobarometric data were combined to constrain and reconstruct a portion of the tectonic history of this orogen. Most extension was accommodated along a system of orogen-parallel, N-S striking normal faults known as the Fjord Region Detachment (FRD) system. The FRD system comprises two temporally distinct, but overlapping, splays just south of 73⁰ N. The lowermost splay is called the Hogedal detachment was active from ca. 417 to 380 Ma, and was active for a second time as recently as ca. 357 Ma. The uppermost splay is the Tindern detachment. This fault was active from ca. 425-423 Ma, exhuming material at rates as fast as 6.5 mm/year. Continued extension in the hanging-wall of this fault accounts for additional denudation at much slower rates over a 25 my time-period. In-between activity on these faults, there is evidence to suggest that middle-crustal thickening continued to occur. Thus, the East Greenland Caledonides preserve evidence for crustal thickening (minimum -16 km) and orogen parallel shear, followed by rapid upper-middle crustal thinning (-13 km), followed by coeval middle-crustal thickening (unknown amount) and upper-crustal thinning (5 km), and ending with crustal collapse (-16 km thinning).
(cont.) This is the first time that an alternation between thrusting and normal faulting has been observed in an over-riding plate during continent-continent collision, and only the second time that it has ever been documented in a collisional orogen. The data imply that there was a fundamental cyclicity between crustal thickening and thinning, consistent with dynamical models of orogenesis in which plate-forces responsible for contraction and gravitational forces responsible for extension, oscillate between periods where one dominates. Furthermore, given the established relationship between topography and synorogenic extension in active mountain belts, it is likely that activity along the Tindern detachment, the earliest splay of the FRD, was controlled by Caledonian paleotopography that formed during the initial stages of orogenesis. The fact that most middle- and upper-crustal extension was restricted to the FRD implies that a localized inherent crustal weakness may have developed after initial movement along the Tindern detachment. Given that late-stage Devonian activity on the FRD may have played a prominent role in the formation of the Devonian basins, which themselves likely controlled the geometry and location of subsequent Mesozoic extension and formation of the North Sea basins, the implication is that the position of rifting of the north Atlantic ocean was partially [pre-determined] inherited from the initial Caledonian paleotopography.
by Arthur P. White.
Ph.D.

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2

Robertson, S. "Late Archaean crustal evolution in the Ivisartoq region, southern west Greenland". Thesis, University of Exeter, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.353048.

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3

Stein, Martin. "Evolution and taxonomy of Cambrian arthropods from Greenland and Sweden". Doctoral thesis, Uppsala University, Department of Earth Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9301.

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Arthropods have a rich fossil record spanning the Phanerozoic. Biomineralized forms such as the extinct trilobites are particularly common and are proven index fossils for biostratigraphy. Forms with an unmineralized cuticle are more rare, preserved only in so called konservat lagerstätten. Cambrian strata of Greenland have yielded rich trilobite faunas with potential for intercontinental correlation of Cambrian strata, but also an exceptionally preserved fauna, the Sirius Passet Lagerstätte. The first part of this thesis is concerned with trilobite biotratigraphy of the provisional Cambrian Series 2 in Greenland. The second part is concerned with exceptionally preserved arthropods from the Sirius Passet Lagerstätte, but also from 'Orsten' deposits from the Cambrian of Sweden.

Perissopyge phenax occurs in the Henson Gletscher and Paralleldal formations spanning the Series 2 and 3 boundary interval in North Greenland. It also occurs in the Sekwi Formation of Yukon Territory, demonstrating that the species may hold potential for correlation within Laurentia. An indeterminate species of Perissopyge is shown to occur in the Ella Island Formation of North-East Greenland together with Olenellus cf. hanseni, which is similar to Olenellus cf. truemani described from the Henson Gletscher Formation. If this correlation is further corroborated it would offer a first tie-point for the An t'Sron Formation of North-West Scotland which yields Fritzolenellus lapworthi, herein reported for the first time from the Bastion Formation which underlies the Ella Island Formation.

Oelandocaris oelandica from ‘Orsten’ deposits in the Cambrian series 3 and 4 boundary interval in Sweden is an early representative of the Crustacean stem lineage. Kiisortoqia avannaarsuensis is a new arthropod from the Sirius Passet Lagerstätte with robust antennulae strikingly similar to the 'raptorial' limb of the problematic anomalocaridids. The ventral morphology of the 'bivalved' Isoxys volucris is described for the first time and compared with other species assigned to Isoxys from Cambrian lagerstätten around the world. Finally, Siriocaris trolla, is a new arthropod that similarities with trilobites and certain ‘trilobitomorphs’ but seems to lack important synapomorphies of these taxa, though this may be due to preservational limitations in the material at hand.

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4

Stripp, Gemma Rachel. "The late-stage evolution of the Skaergaard intrusion, East Greenland". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608729.

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5

Martin, Andrew Richard. "The evolution of the Tugtutoq-Ilimaussaq dyke swarm, southwest Greenland". Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/12582.

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6

Alsulami, Sulaiman Lafi. "Tectonic variation and structural evolution of the West Greenland continental margin". Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7381/.

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The study sets out to unravel the tectonic evolution and lateral structural variation of the West Greenland (Baffin Bay, Davis Strait and Labrador Sea) and to consider its hydrocarbon potential in light of this new evaluation. The study follows a multidisciplinary approach by using 2D seismic, gravity, magnetic, depth-dependent stretching data combined with heat flow and petroleum system modelling. The Western Greenland margin evolved through a complex combination of processes that included multiple phases of extension, varying degrees of subsidence and margin uplift. Basin fill architecture indicates that the margin changes dramatically laterally along the margin. Two rift events were recognized based on architecture of syn-rift sediments. The complex structural variation along the margin is revealed by: the presence of a clear magnetic lineament indicating formation of oceanic crust in Labrador Sea at Chron 31; a good correlation between gravity anomalies in areas of oceanic crust where the extinct spreading axis between Canada and Greenland was identified; areas of continental crust with greater uncertainty in the structure of the continental lithosphere; and greater extension accommodated by the lithosphere in its entirety, rather than by the upper crust alone as indicated by depth-dependent stretching along the margin This study therefore demonstrates that understanding the complex processes involved in multiple-rifting and depth-dependent stretching is important to constraining hydrocarbon potential of passive margin basins.

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7

Lee, Natasha. "The Neoarchaean tectonothermal evolution of the SE Nuuk region, southern West Greenland". Thesis, University of Edinburgh, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520515.

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8

Mader, Marianne M. "From genesis to juxtaposition : the evolution of the Ivisârtoq greenstone belt, southwest Greenland /". Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,64637.

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9

RiCharde, Gabriel E. "GEOTHERMOBAROMETRIC ANALYSIS AND TECTONIC EVOLUTION OF THE LIVERPOOL LAND ECLOGITES, EAST GREENLAND CALEDONIDES". UKnowledge, 2012. http://uknowledge.uky.edu/ees_etds/10.

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Mineral chemistry and thermobarometry of mafic pods in the Liverpool Land Eclogite Terrane (LLET) provide insight into potential relationships with regional high-pressure (HP) and ultrahigh-pressure (UHP) terranes such as the North East Greenland Eclogite Province (NEGEP), the Western Gneiss Region (WGR), and HP granulites in the East Greenland Caledonides at Payer Land. Grt-cpx thermometry and jadeite barometry performed on garnet and omphacite cores in a sequence of retrogressed eclogites give minimum and average P-T values across six samples for eclogite at 18.4 ± 3.7 kbar at 764 ± 156 °C. Granulite facies conditions based on early retrograde Opx-Plag symplectites, garnet rim compositions, and relict omphacite grains give P-T values at 12.7 ± 0.6 kbar at 860 ± 10 °C, based on grt-cpx thermometry and the opx-grt-pl-qtz equilibra. Late retrograde amphibolite facies conditions, marked by matrix plagioclase and biotite and orthopyroxene symplectite replacement by hornblende symplectites, give mean P-T values of 6.8 ± 0.4 kbar at 740 ± 150 °C, based on grt-cpx thermometry and the grt-hbl-plag-qtz equilibra. Thermometers and barometers yield a qualitative P-T path from lower eclogite facies pressures through the granulite facies via hot isothermal and static decompression, preserving symplectite textures, to amphibolite facies conditions via isobaric cooling. The path is consistent with low-pressure WGR eclogites and suggests affinities between the LLET and Baltica.

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10

Swientek, Oliver. "The Greenland Norwegian Seaway climatic and cyclic evolution of Late Jurassic-Early Cretaceous sediments /". [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=965036944.

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11

Lane, Timothy Patrick. "The evolution and dynamic behaviour of the northern Uummannaq Ice Stream System, west Greenland". Thesis, Durham University, 2013. http://etheses.dur.ac.uk/7724/.

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This thesis considers the evolution and dynamic behaviour of the northern Uummannaq Ice Stream System (UISS), a large ice stream which extended to the Greenland shelf edge during the Last Glacial Maximum (LGM). The Uummannaq region has been shown to be dominated by areas of selective linear erosion (SLE) and areal scour. Over multiple glacial cycles, enhanced by favourable geology and uplift, SLE controlled the formation of a confluent fjord system which triggered the onset and development of the UISS. At the LGM, northern UISS ice thicknesses reached 1400-1968 m a.s.l., comparable to data from the southern UISS. However, in the north, thicknesses were not sufficient to overtop fjord confines, with ice flow remaining topographically controlled. The presence of thick, fast ice flowing ice in the onset zone suggests that subglacial conditions within the study area were characterised by intense basal sliding. The evolution of bedforms (roches moutonnées and whalebacks) was influenced by basal ice dynamics, but bedrock type, joints and bedding were also critical controls on bedform morphometry. Deglaciation following the LGM began on the outer shelf by 14.9 kyr, with increased air temperature, rising relative sea-level and bathymetric over-deepening driving the UISS to the outer edge of coastal fjords by 11.4-11.0 kyr. Geochronological data demonstrate that the retreat rate of the northern and southern UISS became highly asynchronous during the early-Holocene. In the south, topographic constrictions stabilised the ice from 11.0-9.3 kyr, before it retreated beyond its present ice margin at 8.7 kyr. Ice in the north became pinned at the mouth of Rink-Karrat Isfjord between 11.6-6.9 kyr, remaining stable through the Holocene Thermal Maximum, demonstrating the ability of topography to override climate and sea-level drivers. Geomorphological and sedimentological evidence has demonstrated that the Svartenhuk Peninsula in the northern Uummannaq region, previously cited as an LGM ice-free enclave, was overrun by ice during the LGM. Ice was sourced from the Svartenhuk interior, and expanded radially to the present coastline. This is contrary to existing work, and suggests there may be a need to reassess the evidence for interstadial, high sea-level conditions throughout Greenland.

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12

Buchanan, John Wesley Steltenpohl Mark G. "Tectonic evolution of a Caledonian-aged continental basement eclogite terrane in Liverpool Land, East Greenland". Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Geology_and_Geography/Thesis/Buchanan_John_21.pdf.

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13

Hermann, Tobias [Verfasser], Gerhard [Akademischer Betreuer] Jentzsch, Thomas [Akademischer Betreuer] Jahr y Wilfried [Akademischer Betreuer] Jokat. "The Northeast Greenland Margin - Tectonic Evolution / Tobias Hermann. Gutachter: Gerhard Jentzsch ; Thomas Jahr ; Wilfried Jokat". Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2014. http://d-nb.info/1047578875/34.

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14

McGregor, Eoin David. "Onshore-offshore relationships and basin evolution along the west Greenland and conjugate Baffin-Labrador margins". Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=203963.

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The passive margins of west Greenland and Baffin/Labrador (sedimentary basins and onshore topography therein) developed mainly as a result of Late Mesozoic and Cenozoic rifting processes in the Davis Strait area. The origin and age of topography along the west Greenland margin is a matter of continued debate. Analysis of seismic reflection profiles and 1-D modelling of wells along the Greenland margin of Davis Strait demonstrate that the data are consistent with a model of ancient continental topography affected by Late Cretaceous-early Palaeocene rifting followed by thermal subsidence, where offshore Neogene tectonic uplift is not required. First order analysis of apatite fission track data from southeast Baffin Island reveals that samples experienced contemporaneous cooling from an array of initial temperatures. 1-D modelling suggests that cooling through the partial annealing zone occurred over discrete periods ranging from 100 to 300 Ma. Modelling the 3-D exhumation of a heterogeneous crust demonstrates that some of the variability in observed fission track ages could be attributed to thermal crustal heterogeneity. The results show that the observed data are consistent with a simple exhumation scenario where the present-day high topography is a remnant of that created during Palaeoproterozoic orogenies. In view of new geophysical constraints and newly assessed well data, a number of the exploration wells located on the conjugate west Greenland and Baffin/Labrador margins have been re-modelled to determine whether any new insights might be derived. Model results imply that southeast Baffin area was subject to more intense rifting prior to the onset of magmatism in the early Palaeocene. This in turn suggests that magmatism in the area was related to rifting and not linked to the arrival of a mantle plume at the beginning of the Palaeocene. The thermal histories presented here are consistent with those required for hydrocarbon generation.

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15

Huselbee, Maxine Yvonne. "Late Cambrian to earliest Ordovician (Ibexian) conodont evolution and biogeography of Greenland and northwest Scotland". Thesis, University of Birmingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597114.

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The Late Cambrian to earliest Ordovician coniform-dominated conodont faunas recovered from the platform carbonate sequences of western North Greenland, central East Greenland, and northwest Scotland comprise a total of22 multi-element genera. Four genera and seven species are new to this study. Although the faunas exhibit a strong North American Midcontinent Province affinity, a FranklinianlArctic fauna (typified by Pagetopetalon gen. nov. and Loxognathodus Ji and Barnes) has also been identified - a fauna which was restricted to the margins ofthe Laurentian craton (Greenland, northwest Scotland, western Newfoundland, and the Canadian Arctic Islands). Furthermore, conodonts recovered from the upper Eilean Dubh Formation of northwest Scotland, traditionally considered to be faunally barren, have unequivocally established an Ordovician (c. lindstromi Biozone) age; thus placing the Cambrian-Ordovician boundary at an interval within the formation. Revised apparatus reconstructions have been proposed for three genera: A septimembrate apparatus is proposed for Variabiloconus bassleri (Pander), and its homology with that of the Fauna 0 taxa Aloxoconus stauffiri (Furnish), Colaptoconus quadraplicatus (Branson and Mehl), Eucharodus parallelus (Branson and Mehl) and Ulrichodina deflexus Furnish, has significant implications regarding the actual diversity of samples over this interval. In contrast, Rossodus Repetski and Ethington is reconstructed with a quinquemembrate apparatus ofprioniodontid affinity (based on P element morphology). A trimembrate, crushing apparatus has also been proposed for Clavohamulus Furnish as a consequence of its comparative morphology with certain species of the Raja.

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16

Leeson, Amber Alexandra. "Insights from observations and modelling into the evolution of superglacial lakes on the Greenland ice sheet". Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5060/.

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Supraglacial lakes (SGLs) form when runoff (meltwater + rain) pools in depressions on the Greenland ice sheet (GrIS). SGLs can collectively affect seasonal ice sheet flow rates when they drain episodically; although the net impact on flow speed is uncertain. In this thesis: 1) a new model of SGL Initiation and Growth (the SLInG model) is presented, 2) existing SGL observations are evaluated and combined to form a single optimised dataset, 3) these data are used to evaluate the model and 4) this model is used to investigate past trends in SGL evolution in south west Greenland. SLInG is a 2-dimensional transient hydrology model which routes runoff, which has been simulated using a regional climate model, over a digital elevation model (DEM) of the ice sheet surface. Water is routed using Darcy’s law for flow through a porous medium and Manning’s equation for open channel flow, and is allowed to collect in depressions in the DEM, thus forming SGLs. Observations of SGLs can be temporally sparse and variation in reported lake frequency can be significant between datasets. Three observational datasets of SGLs, automatically derived from satellite data, were found to omit a sizeable (29 to 48%) fraction of lakes identified manually. These datasets were combined using a hierarchical scheme, leading to a 67% increase in the number of lakes reported. By comparison with satellite observations, SLInG is found to be 19 times more likely to correctly predict the location, or absence, of a lake, than not. In addition, simulated and observed lake onset dates are highly correlated (r= ~0.8) and model estimates of the rate of growth of lake covered area are, on average, just 14% greater than observed values. SLInG was forced with 40 years of reanalysis data in order to investigate historical variation in the temporal evolution of SGLs. SLInG shows that SGLs have responded to recent dramatic changes in local climate by migrating inland by 150 m a.s.l. (3.75 m a.s.l. per year) during 1971-2010. This modelled trend is in good agreement with recent satellite observations and suggests that SGLs, by forming and draining at higher elevations, where pre-existing surface-bed conduits such as moulins and crevasses are rare, may contribute more significantly to ice sheet dynamics in the future.

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17

Starkey, Natalie. "Evolution of the Earth's mantle-crust-atmosphere system from the trace element and isotope geochemistry of the plume-mantle reservoir". Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/5934.

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The 62 million year old lava flows of Baffin Island and West Greenland represent the earliest phase of magmatism in the North Atlantic Igneous Province (NAIP). These picritic lavas are characterised by high magnesium contents owing to their high proportion of olivine crystals. The parental magmas for the picrites are likely to have accumulated olivine crystals on their transit through the lithosphere and crust. Debate over the origin of accumulated crystals in the lavas results in uncertainty in the temperature and composition of the parental magmas for the early NAIP. The magnesium-rich olivine crystals (up to Fo93) in the picrites of this study are shown not to have a xenocrystic origin. The samples, therefore, support the inference of high potential temperatures for the Baffin Island-West Greenland magmas, ~200oC above ambient mantle. The picrites of Baffin Island and West Greenland display the highest terrestrial magmatic 3He/4He (up to 50 Ra, where Ra is the atmospheric value 1.39 x 10-6), values that are considerably higher than the highest 3He/4He in contemporary ocean island basalts, which reach a maximum of ~30 Ra. High 3He/4He in Baffin Island and West Greenland are associated with a wide range of incompatible trace element and lithophile radiogenic isotopic compositions, not dissimilar to the range of compositions displayed by lavas at mid-ocean ridges, and overlapping the range displayed by most northern hemisphere ocean island basalts. Crustal contamination modelling in which high-grade Proterozoic crustal basement rocks are mixed with depleted parents cannot account for the compositional trends displayed by the picrites. Major and trace element compositions were determined on melt inclusions in high- 3He/4He picrites that span a wide range of whole-rock incompatible trace element and radiogenic isotopic compositions. The melt inclusions support the findings from the whole-rock study since melt inclusion compositions reflect the composition of their associated whole-rock, with no anomalous compositions present. In addition, there is no evidence for a contribution of a proportion of depleted melts to the source of the relatively enriched whole-rock samples. Therefore, since all melt inclusions were contained within high-3He/4He samples, it is shown that high 3He/4He is a feature of both depleted and relatively enriched melt compositions. The wide range in whole-rock compositions of the Baffin Island and West Greenland picrites represents that of the sub-lithospheric mantle source region and is inconsistent with derivation of the picrites from residues of ancient mantle depletion. The apparent decoupling of helium from trace elements and radiogenic isotopes is hard to reconcile with simple mixing of a high-helium concentration, high-3He/4He reservoir with various depleted and enriched helium-poor mantle reservoirs. It is possible that primordial helium has diffused into a reservoir with a composition similar to that of the convecting upper mantle. However, this must have occurred after the development of existing mantle heterogeneity. The high-3He/4He picrites require the existence of a deep, primordial helium-rich reservoir. Whether this reservoir is present in the upper or deep mantle, or even the core, remains uncertain.

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18

Stone, Emma Jane. "The impact of vegetation feedbacks on the evolution of the Greenland ice-sheet under future and past climates". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535472.

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19

Müller, Sascha [Verfasser], Annika [Akademischer Betreuer] Dziggel y Jochen [Akademischer Betreuer] Kolb. "Metamorphic evolution of relict eclogite-facies rocks in the Paleoproterozoic Nagssugtoqidian Orogen, South-East Greenland / Sascha Müller ; Annika Dziggel, Jochen Kolb". Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1192375580/34.

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20

Simpson, Matthew James Ross. "The evolution of the Greenland Ice Sheet from the Last Glacial Maximum to present-day : an assessment using glaciological and Glacial Isostatic Adjustment modelling". Thesis, Durham University, 2009. http://etheses.dur.ac.uk/283/.

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In this thesis we constrain a three-dimensional thermomechanical model of Greenland ice sheet (GrIS) evolution from the Last Glacial Maximum (LGM, 21 ka BP) to the present-day using, primarily, observations of relative sea level (RSL) as well as field data on past ice extent. The new model (Huy2) fits a majority of the observations and is characterised by a number of key features: (i) the ice sheet had an excess volume (relative to present) of 4.1 m ice-equivalent sea level at the LGM, which increased to reach a maximum value of 4.6 m at 16.5 ka BP; (ii) retreat from the continental shelf was not continuous around the entire margin, as there was a Younger Dryas readvance in some areas. The final episode of marine retreat was rapid and relatively late (c. 12 ka BP), leaving the ice sheet land based by 10 ka BP; (iii) in response to the Holocene Thermal Maximum (HTM) the ice margin retreated behind its present-day position by up to 80 km in the southwest, 20 km in the south and 80 km in a small area of the northeast. As a result of this retreat the modelled ice sheet reaches a minimum extent between 5 and 4 ka BP, which corresponds to a deficit volume (relative to present) of 0.17 m ice-equivalent sea level. The results suggest that remaining discrepancies between the model and the observations are likely associated with non-Greenland ice load, differences between modelled and observed present-day ice elevation around the margin, lateral variations in Earth structure and/or the pattern of ice margin retreat. Predictions of present-day vertical land motion generated using the new Huy2 model are highly sensitive to variations of upper mantle viscosity. Depending on the Earth model adopted, different periods of post-LGM ice loading change dominate the present-day response in particular regions of Greenland. These results will be a useful resource when interpreting existing and future observations of vertical land motion in Greenland. In comparison to the sparse number of GPS observations available, predictions from the Huy2 model are in good agreement to the absolute measurements from south and southwest Greenland. This suggests that the response of the ice sheet to the HTM is reasonably well produced by the Huy2 model and, thus, corroborates our earlier findings. Uplift predictions generated using a surface mass balance reconstruction of the GrIS (Wake et al., 2009), which covers the period 1866-2005, show that decadal-scale ice mass variability over the last c. 140 years plays a small role in determining the present-day viscous response (it is as large as ±0.2 mm/yr). Results from the same reconstruction show that high rates of peripheral thinning in west and southwest Greenland from 1995 to 2005 (due to surface mass balance changes) generate elastic uplift rates over 6 mm/yr. In the final part of the thesis, we examine how non-Greenland ice mass loss influenced vertical land motion and sea-level change around Greenland over the last deglaciation and consider the implications for GrIS evolution. Results from this analysis suggest non-Greenland solid Earth deformation had little impact on the evolution ice sheet. Sea-level change around Greenland which is driven by non-Greenland ice mass loss departs from the associated eustatic signal; largely because of the close proximity of the late North American ice sheets (NAIS). Non-Greenland RSL change is also spatially non-uniform and is characterised by a distinct east-west gradient. For example, we find that from 16 to 14 ka BP rates of sea-level rise remained relatively low in the west (0-2 m/ka), whereas, those in the east reach values between 6 and 8 m/ka (although these results are sensitive to the source of meltwater, in particular, the relative partitioning of meltwater pulse 1A (mwp-1A, 14.2 ka BP) between the North American and Antarctic ice sheets). If the marine breakup of the GrIS was forced by non-Greenland RSL change, then we would expect the retreat of the ice sheet to reflect the sea-level changes described. A preliminary modelling study suggests that, assuming a conventional ice sheet model calving treatment, a more realistic sea-level forcing results in a pattern of ice margin retreat which is at least partly due to spatial variations in non-Greenland RSL change. Thus, the modelled marine retreat is generally earlier in east Greenland and later in the west than for when non-Greenland RSL change is not accounted for - this pattern of ice margin retreat is generally consistent with observations from the continental shelf.

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21

Schlindwein, Vera. "Architecture and evolution of the continental crust of East Greenland from integrated geophysical studies = Aufbau und Entwicklungsgeschichte der kontinentalen Kruste Ostgrönlands aus integrierten geophysikalischen Untersuchungen /". Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1998. http://www.gbv.de/dms/bs/toc/245800581.pdf.

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22

Fabre, Adeline. "Modélisation 3D de l'écoulement des calottes glaciaires : application à la calotte du Groenland et aux calottes de l'hémisphère nord au dernier maximum glaciaire". Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10014.

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Le systeme climatique terrestre est forme de plusieurs composantes qui interagissent etroitement (atmosphere, calottes de glace, oceans, lithosphere et biosphere). La modelisation numerique permet d'etudier ces interactions. Dans ce travail, l'ecoulement de plusieurs calottes glaciaires est modelise et on s'attache particulierement a l'etude de leurs interactions avec l'atmosphere. Celles-ci sont determinees par l'altitude de la surface de la calotte, les temperatures en surface et l'accumulation. Un modele 3d d'ecoulement de calotte glaciaire, developpe au sein de l'equipe modelisation du lgge, est presente. Il est teste sur une calotte theorique dans le cadre d'un projet europeen d'intercomparaison de modeles. Il est ensuite applique a la calotte du groenland, en simulant la reponse de la calotte sous des climats differents du climat actuel et en etudiant son evolution au cours du dernier cycle interglaciaire-glaciaire. La sensibilite du modele a la parametrisation de l'accumulation est mise en evidence. Le modele est enfin applique a la reconstruction des calottes de glace presentes dans l'hemisphere nord (laurentide et fennoscandie) au dernier maximum glaciaire (il y a environ 21 000 ans). Trois methodes sont utilisees pour calculer les conditions climatiques en entree du modele. Dans les deux premieres, ces conditions sont determinees par une parametrisation calibree sur les valeurs actuelles: les resultats ainsi obtenus ne sont pas satisfaisants. La troisieme methode utilise les temperatures en surface et les precipitations issues de simulations du climat du dernier maximum glaciaire, realisees avec le modele de circulation generale de l'atmosphere du lmd. Le couplage entre les deux modeles necessite un traitement de donnees complexe, mais les calottes obtenues sont en meilleur accord avec les donnees geologiques sur l'extension et l'epaisseur des calottes a cette epoque

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Swientek, Oliver [Verfasser]. "The Greenland Norwegian Seaway : climatic and cyclic evolution of Late Jurassic-Early Cretaceous sediments / vorgelegt von Oliver Swientek". 2002. http://d-nb.info/965036944/34.

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Tesis sobre el tema "Greenland evolution"

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