Composition and deformation patterns of the caprock on salt extrusions in southern Iran - Field study on the Karmostaj and Siah Taq diapirs

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F21%3A00546423" target="_blank" >RIV/67985530:_____/21:00546423 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00025798:_____/21:00000197 RIV/00216208:11310/21:10438764

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/abs/pii/S0191814121001462" target="_blank" >https://www.sciencedirect.com/science/article/abs/pii/S0191814121001462</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jsg.2021.104422" target="_blank" >10.1016/j.jsg.2021.104422</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Composition and deformation patterns of the caprock on salt extrusions in southern Iran - Field study on the Karmostaj and Siah Taq diapirs

Popis výsledku v původním jazyce

Two iconic salt diapirs in the Zagros Mountains in Iran – Karmostaj (Gach) and Siah Taq – are regarded as world-class examples of salt extrusions and are frequently called salt glaciers. However, our field survey revealed that their glacier-like parts are formed by thick, variegated and deformed caprock, only locally mixed with salt. Caprock is a layer of insoluble residuum that consists primarily of dissolution breccia and gypsum surrounding blocks of non-halite lithologies of the original evaporite sequence. Deformation within the caprock was accommodated primarily by shearing along gypsum-rich zones (gypsum mylonites) that surround subdomains of dissolution breccia and folded and fragmented blocks of carbonates and siliciclastics. Ductile flow in these mylonite shear zones was accommodated by pressure solution-precipitation creep of the lath-shaped gypsum grains. The ductile shearing of gypsum was locally accompanied by increased fluid-pore pressure driven fracturing of the surrounding lithologies. Since the subsurface shape of the salt diapirs is unknown, we present three hypothetical scenarios trying to explain the extrusion process of the studied diapirs and the associated deformation history of their caprocks. The diapiric structures represent either, 1) the remnants of degraded paleoglaciers, 2) advancing salt extrusions, or 3) only slightly reactivated, wide diapirs. To test these hypothetical scenarios, a geophysical survey is required to gain insights into the subsurface structures of the exposed diapirs and salt sheets.

Název v anglickém jazyce

Composition and deformation patterns of the caprock on salt extrusions in southern Iran - Field study on the Karmostaj and Siah Taq diapirs

Popis výsledku anglicky

Two iconic salt diapirs in the Zagros Mountains in Iran – Karmostaj (Gach) and Siah Taq – are regarded as world-class examples of salt extrusions and are frequently called salt glaciers. However, our field survey revealed that their glacier-like parts are formed by thick, variegated and deformed caprock, only locally mixed with salt. Caprock is a layer of insoluble residuum that consists primarily of dissolution breccia and gypsum surrounding blocks of non-halite lithologies of the original evaporite sequence. Deformation within the caprock was accommodated primarily by shearing along gypsum-rich zones (gypsum mylonites) that surround subdomains of dissolution breccia and folded and fragmented blocks of carbonates and siliciclastics. Ductile flow in these mylonite shear zones was accommodated by pressure solution-precipitation creep of the lath-shaped gypsum grains. The ductile shearing of gypsum was locally accompanied by increased fluid-pore pressure driven fracturing of the surrounding lithologies. Since the subsurface shape of the salt diapirs is unknown, we present three hypothetical scenarios trying to explain the extrusion process of the studied diapirs and the associated deformation history of their caprocks. The diapiric structures represent either, 1) the remnants of degraded paleoglaciers, 2) advancing salt extrusions, or 3) only slightly reactivated, wide diapirs. To test these hypothetical scenarios, a geophysical survey is required to gain insights into the subsurface structures of the exposed diapirs and salt sheets.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

<a href="/cs/project/GC20-18647J" target="_blank" >GC20-18647J: Vliv caprocku na dynamiku růstu solných těles v Iránu</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Journal of Structural Geology

ISSN

0191-8141

e-ISSN

1873-1201

Svazek periodika

151

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

20

Strana od-do

104422

Kód UT WoS článku

000692112300001

EID výsledku v databázi Scopus

2-s2.0-85111918627