Trace and rare-earth element characteristics of fine-grained sediments in the Upper Triassic Xujiahe Formation in the western Sichuan Basin, SW China: implications for the provenance and depositional environment

2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Yu Yu ◽  
Liangbiao Lin ◽  
Hongli Nan
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Sichuan Basin ◽  
Depositional Environment ◽  
Earth Element ◽  
Upper Triassic ◽  
Xujiahe Formation ◽  
Western Sichuan ◽  
Fine Grained ◽  
Western Sichuan Basin

scholarly journals The Origin of Quartz Cement in the Upper Triassic Second Member of the Xujiahe Formation Sandstones, Western Sichuan Basin, China

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1890
Author(s):  
Jie Ren ◽  
Zhengxiang Lv ◽  
Honghui Wang ◽  
Jianmeng Wu ◽  
Shunli Zhang
Keyword(s):  
Sichuan Basin ◽  
Secondary Ion Mass Spectrometry ◽  
Trace Element Composition ◽  
Upper Triassic ◽  
Al2o3 Content ◽  
Xujiahe Formation ◽  
Western Sichuan ◽  
Rock Fragments ◽  
Quartz Cement ◽  
Western Sichuan Basin

High-precision in situ δ18O values obtained using secondary ion mass spectrometry (SIMS) for μm-size quartz cement are applied to constrain the origin of the silica in the deep-buried Upper Triassic second member of Xujiahe Formation tight sandstones, western Sichuan Basin, China. Petrographic, cathodoluminescence (CL), and fluid inclusion data from the quartz cements in the Xu2 sandstones indicate three distinct, separate quartz precipitation phases (referred to as Q1, Q2, and Q3). The Q1 quartz cement was formed at temperatures of approximately 56–85 °C and attained the highest δ18O values (ranging from 18.3 to 19.05‰ Vienna Standard Mean Ocean Water (VSMOW)). The Q2 quartz cement was generated at temperatures of approximately 90–125 °C, accompanying the main phase of hydrocarbon fluid inclusions, with the highest Al2O3 content and high δ18O values (ranging from 15 to 17.99‰ VSMOW). The Q3 quartz cement was formed at temperatures of approximately 130–175 °C, with the lowest δ18O values (ranging from 12.79 to 15.47‰ VSMOW). A portion of the Q2 and Q3 quartz cement has a relatively high K2O content. The dissolution of feldspar and volcanic rock fragments was likely the most important source of silica for the Q1 quartz cement. The variations in δ18O(water) and trace element composition from the Q2 quartz cement to the Q3 quartz cement suggest that hydrocarbon emplacement and water-rock interactions greatly altered the chemistry of the pore fluid. Feldspar dissolution by organic acids, clay mineral reactions (illitization and chloritization of smectite), and pressure dissolution were the main sources of silica for the Q2 and Q3 quartz cements, while transformation of the clay minerals in the external shale unit was a limited silica source.

Diagenesis of tight sandstone reservoirs of Xujiahe Formation (Upper Triassic), the Xinchang Gas Field, western Sichuan Basin, China

2019 ◽  
Vol 55 (6) ◽  
pp. 4604-4624
Author(s):  
Yi‐Jiang Zhong ◽  
Ke‐Ke Huang ◽  
Li‐Ming Ye ◽  
Ye‐Fang Lan ◽  
Lei Liu
Keyword(s):  
Sichuan Basin ◽  
Upper Triassic ◽  
Tight Sandstone ◽  
Gas Field ◽  
Xujiahe Formation ◽  
Western Sichuan ◽  
Sandstone Reservoirs ◽  
Western Sichuan Basin

Paleoenvironments revealed by rare-earth element systematics in vertebrate bioapatite from the Lower Devonian of Svalbard

2016 ◽  
Vol 53 (8) ◽  
pp. 788-794
Author(s):  
Živilė Žigaitė ◽  
Alexandre Fadel ◽  
Alberto Pérez-Huerta ◽  
Teresa Jeffries ◽  
Daniel Goujet ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Element ◽  
Lower Devonian ◽  
Depositional Environment ◽  
Earth Element ◽  
Long Distance ◽  
Dental Tissues ◽  
Abundance Patterns ◽  
The Eu

In situ rare-earth element (REE) compositions have been measured in early vertebrate microremains from the Lower Devonian basin of Andrée Land (Svalbard), with the aim of obtaining information about their early depositional environment and potential reworking. Vertebrate microremains with different histology were used for the analyses, sourced from two different localities of marginal marine to freshwater sediments from geographically distant parts of the Grey Hœk Formation (Skamdalen and Tavlefjellet members). We selected thelodont and undescribed ?chondrichthyan scales, which allowed us to define potential taxonomic, histological, and taphonomic variables of the REE uptake. Results showed REE concentrations to be relatively uniform within the scales of each taxon, but apparent discrepancies were visible between the studied localities and separate taxa. The compilation of REE abundance patterns as well as REE ratios have revealed that thelodont and ?chondrichthyan originating from the same locality must have had different burial and early diagenetic histories. The shapes of the REE profiles, together with the presence and absence of the Eu and Ce anomalies, equally suggested different depositional and diagenetic environments for these two sympatric taxa resulting from either stratigraphical or long-distance reworking. The REE concentrations appear to have visible differences between separate dental tissues, particularly between enameloid and dentine of thelodonts, emphasizing the importance of in situ measurements in microfossil biomineral geochemistry.

Sign in / Sign up

Export Citation Format

Share Document