High-temperature fracturing and subsequent grain-size-sensitive creep in lower crustal gabbros: Evidence for coseismic loading followed by creep during decaying stress in the lower crust?

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11310%2F15%3A10296353" target="_blank" >RIV/00216208:11310/15:10296353 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1002/2014JB011708" target="_blank" >http://dx.doi.org/10.1002/2014JB011708</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/2014JB011708" target="_blank" >10.1002/2014JB011708</a>

Jazyk výsledku

angličtina

Název v původním jazyce

High-temperature fracturing and subsequent grain-size-sensitive creep in lower crustal gabbros: Evidence for coseismic loading followed by creep during decaying stress in the lower crust?

Popis výsledku v původním jazyce

The mechanism of shear zone formation in lower crustal, relatively dry rocks is still poorly understood. We have studied the high-temperature deformation of the Hasvik gabbro (northern Norway) which commences by fracturing. The 10-20 mu m wide fracturesshow little displacement. The fine-grained plagioclase and orthopyroxene in the fractures lack a crystallographic preferred orientation (CPO) or a systematic crystallographic orientation with respect to the host grains. Fractures grade into narrow shearzones, which are composed of fine (10-20 mu m), equant grains of recrystallized plagioclase, amphibole, and pyroxene. Recrystallized plagioclase and pyroxene have compositions different from the magmatic grains, suggesting that they have formed by nucleation and growth. Based on conventional plagioclase-amphibole thermobarometry, the shear zones have formed at temperatures and pressures of 700-750 degrees C and 0.5-0.6GPa. The observed primary minerals cut by fractures suggest high-tempe

Název v anglickém jazyce

High-temperature fracturing and subsequent grain-size-sensitive creep in lower crustal gabbros: Evidence for coseismic loading followed by creep during decaying stress in the lower crust?

Popis výsledku anglicky

The mechanism of shear zone formation in lower crustal, relatively dry rocks is still poorly understood. We have studied the high-temperature deformation of the Hasvik gabbro (northern Norway) which commences by fracturing. The 10-20 mu m wide fracturesshow little displacement. The fine-grained plagioclase and orthopyroxene in the fractures lack a crystallographic preferred orientation (CPO) or a systematic crystallographic orientation with respect to the host grains. Fractures grade into narrow shearzones, which are composed of fine (10-20 mu m), equant grains of recrystallized plagioclase, amphibole, and pyroxene. Recrystallized plagioclase and pyroxene have compositions different from the magmatic grains, suggesting that they have formed by nucleation and growth. Based on conventional plagioclase-amphibole thermobarometry, the shear zones have formed at temperatures and pressures of 700-750 degrees C and 0.5-0.6GPa. The observed primary minerals cut by fractures suggest high-tempe

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

DC - Seismologie, vulkanologie a struktura Země

OECD FORD obor

—

Projekt

<a href="/cs/project/GA14-15632S" target="_blank" >GA14-15632S: Dynamika migrace tavenin a deformace hornin ve spodní kůře orogenů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2015

Kód důvěrnosti údajů

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

Název periodika

JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH

ISSN

2169-9313

e-ISSN

—

Svazek periodika

120

Číslo periodika v rámci svazku

5

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

23

Strana od-do

3119-3141

Kód UT WoS článku

000356454500017

EID výsledku v databázi Scopus

2-s2.0-84935922147