Re–Os and Sr Isotopic Study of Permian–Triassic Sedimentary Rocks from the Himalaya: Shale Chronology and Carbonate Diagenesis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985831%3A_____%2F21%3A00541839" target="_blank" >RIV/67985831:_____/21:00541839 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.mdpi.com/2075-163X/11/4/417" target="_blank" >https://www.mdpi.com/2075-163X/11/4/417</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/min11040417" target="_blank" >10.3390/min11040417</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Re–Os and Sr Isotopic Study of Permian–Triassic Sedimentary Rocks from the Himalaya: Shale Chronology and Carbonate Diagenesis

Popis výsledku v původním jazyce

Sedimentary rocks from the Himalayas are well-preserved archives of the Neo-Tethys oceanic conditions. In this contribution, Re–Os isotopic systematics of black shales from the Gungri Formation, Spiti valley and siltstones from the Khunamuh Formation, Guryul Ravine have been investigated to constrain their depositional ages. The Re–Os isochron for the Gungri shales yields a depositional age of 255 ± 22 Ma (2δ, n = 8, MSWD (Mean Square Weighted Deviation) = 5.7), consistent with available biostratigraphic information. The initial 187Os/188Os ratio (0.60 ± 0.13) is similar to that reported for the Late Permian shales, indicating the connection of the Neo-Tethys with the global ocean. In contrast, the Re–Os systematic is found to be non-isochronous for the Guryul Ravine section, a proximal site with a strong influence of seismic/Tsunami events. Global compilation of 187Re/188Os ratios in Late Permian shales and bathymetric distribution of the Re/Os ratios point to strong role of Re/Os uptake by macroalgae, in addition to oceanic pH and redox state, in regulating the Re–Os systematic in shales. The 87Sr/86Sr ratios for the Induan carbonates from the Spiti (0.71551–0.71837) are higher than to that expected for the Lower Triassic ocean (~0.707). Co variations of Sr and 87Sr/86Sr with Mn concentrations establish the diagenetic alteration of these carbonates.

Název v anglickém jazyce

Re–Os and Sr Isotopic Study of Permian–Triassic Sedimentary Rocks from the Himalaya: Shale Chronology and Carbonate Diagenesis

Popis výsledku anglicky

Sedimentary rocks from the Himalayas are well-preserved archives of the Neo-Tethys oceanic conditions. In this contribution, Re–Os isotopic systematics of black shales from the Gungri Formation, Spiti valley and siltstones from the Khunamuh Formation, Guryul Ravine have been investigated to constrain their depositional ages. The Re–Os isochron for the Gungri shales yields a depositional age of 255 ± 22 Ma (2δ, n = 8, MSWD (Mean Square Weighted Deviation) = 5.7), consistent with available biostratigraphic information. The initial 187Os/188Os ratio (0.60 ± 0.13) is similar to that reported for the Late Permian shales, indicating the connection of the Neo-Tethys with the global ocean. In contrast, the Re–Os systematic is found to be non-isochronous for the Guryul Ravine section, a proximal site with a strong influence of seismic/Tsunami events. Global compilation of 187Re/188Os ratios in Late Permian shales and bathymetric distribution of the Re/Os ratios point to strong role of Re/Os uptake by macroalgae, in addition to oceanic pH and redox state, in regulating the Re–Os systematic in shales. The 87Sr/86Sr ratios for the Induan carbonates from the Spiti (0.71551–0.71837) are higher than to that expected for the Lower Triassic ocean (~0.707). Co variations of Sr and 87Sr/86Sr with Mn concentrations establish the diagenetic alteration of these carbonates.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

—

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

Minerals

ISSN

2075-163X

e-ISSN

2075-163X

Svazek periodika

11

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

15

Strana od-do

417

Kód UT WoS článku

000643330600001

EID výsledku v databázi Scopus

2-s2.0-85104102693