Growth of primordial continents by cycles of oceanic lithosphere subductions: Evidence from tilted seismic anisotropy supported by geochemical and petrological findings

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F20%3A00523731" target="_blank" >RIV/67985530:_____/20:00523731 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S2451912X19300558" target="_blank" >https://www.sciencedirect.com/science/article/pii/S2451912X19300558</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.sesci.2019.12.003" target="_blank" >10.1016/j.sesci.2019.12.003</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Growth of primordial continents by cycles of oceanic lithosphere subductions: Evidence from tilted seismic anisotropy supported by geochemical and petrological findings

Popis výsledku v původním jazyce

Formation of the first continents belongs to fundamental questions regarding the evolution of the Earth. Though the growth of early crust is often debated, role of the mantle lithosphere that represents the biggest volume of continents is often overlooked, particularly in geologic interpretations of tectonic processes. This is mainly due to difficulties in its imaging and uncertainty in its rheology. Investigation of seismic anisotropy from propagation of teleseismic P and S waves in three dimensions (3D), i.e., with no limitation imposed on the symmetry axis orientation into the horizontal or vertical directions, provides a unique constraint on tectonic fabrics and character of past and present-day deformations of the continental lithosphere. In this paper, we collect independent findings from seismology, petrology and geochemistry to support our 3D anisotropic model of mantle lithosphere with tilted symmetry axes, derived from data of passive seismic experiments organised in tectonically different domains of Archean, Proterozoic and Phanerozoic provinces of Europe. Olivine preferred orientation, formed by mantle convection in the oceanic mantle lithosphere due to its spreading on both sides of the midocean ridges, is a prerequisite for the tilted anisotropies that we model in the continents. We have explained the systematically oriented dipping fabrics in the continental mantle lithosphere by successive subductions of ancient oceanic plates and their accretions enlarging primordial continent cores. Consequent continental break-ups and assemblages of wandering micro-plates preserve “frozen” anisotropic fabrics and create patchwork structures of the present-day continents. Supporting arguments for such model arise from petrological and geochemical studies indicating that continental mantle peridotites formed in oceanic environments and became “continental” after significant thickening or underthrusting.

Název v anglickém jazyce

Growth of primordial continents by cycles of oceanic lithosphere subductions: Evidence from tilted seismic anisotropy supported by geochemical and petrological findings

Popis výsledku anglicky

Formation of the first continents belongs to fundamental questions regarding the evolution of the Earth. Though the growth of early crust is often debated, role of the mantle lithosphere that represents the biggest volume of continents is often overlooked, particularly in geologic interpretations of tectonic processes. This is mainly due to difficulties in its imaging and uncertainty in its rheology. Investigation of seismic anisotropy from propagation of teleseismic P and S waves in three dimensions (3D), i.e., with no limitation imposed on the symmetry axis orientation into the horizontal or vertical directions, provides a unique constraint on tectonic fabrics and character of past and present-day deformations of the continental lithosphere. In this paper, we collect independent findings from seismology, petrology and geochemistry to support our 3D anisotropic model of mantle lithosphere with tilted symmetry axes, derived from data of passive seismic experiments organised in tectonically different domains of Archean, Proterozoic and Phanerozoic provinces of Europe. Olivine preferred orientation, formed by mantle convection in the oceanic mantle lithosphere due to its spreading on both sides of the midocean ridges, is a prerequisite for the tilted anisotropies that we model in the continents. We have explained the systematically oriented dipping fabrics in the continental mantle lithosphere by successive subductions of ancient oceanic plates and their accretions enlarging primordial continent cores. Consequent continental break-ups and assemblages of wandering micro-plates preserve “frozen” anisotropic fabrics and create patchwork structures of the present-day continents. Supporting arguments for such model arise from petrological and geochemical studies indicating that continental mantle peridotites formed in oceanic environments and became “continental” after significant thickening or underthrusting.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10507 - Volcanology

Projekt

<a href="/cs/project/EF16_013%2F0001800" target="_blank" >EF16_013/0001800: Distribuovaný systém observatorních a terénních měření geofyzikálních polí</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Solid Earth Sciences

ISSN

2451-912X

e-ISSN

—

Svazek periodika

5

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

19

Strana od-do

50-68

Kód UT WoS článku

000536950600005

EID výsledku v databázi Scopus

—