Unraveling the parameters controlling diagenetic evolution in relatively shallow-buried, syn-tectonic ramp limestones (Upper Cretaceous), United Arab Emirates

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F25%3A73633888" target="_blank" >RIV/61989592:15310/25:73633888 - isvavai.cz</a>

Result on the web

<a href="https://www.sciencedirect.com/science/article/pii/S0264817225003241" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0264817225003241</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.marpetgeo.2025.107607" target="_blank" >10.1016/j.marpetgeo.2025.107607</a>

Result language

angličtina

Original language name

Unraveling the parameters controlling diagenetic evolution in relatively shallow-buried, syn-tectonic ramp limestones (Upper Cretaceous), United Arab Emirates

Original language description

This study utilizes petrographic, geochemical, and fluid-inclusion microthermometric analyses to unravel the controls on the distribution of diagenetic alterations of shallow-buried Upper Cretaceous syn-tectonic, foreland, ramp limestones of the United Arab Emirates. The diagenetic alterations are linked to porewater evolution during the tectonic evolution of the basin, as well as to the depositional facies and sequence stratigraphy. Limited improvement of reservoir quality was promoted by dissolution of allochems and formation of moldic pores. Porosity reductionensued mostly from: (i) cementation by meteoric waters and by hot basinal/hydrothermal brines with wide ranges of delta 18OV-PDB (-6.3 %o to -3.2 %o) and precipitation temperatures (Th approximate to 65-125 degrees C; salinity approximate to 16-22 wt% NaCl eq), and (ii) mechanical compaction of ductile peloids formed by micritization of allochems. Micritization, notably prevalent in the transgressive lagoon and upper ramp slope packstones, as well as in the regressive shoal grainstones below marine-flooding surfaces, led to the development of abundant microporosity. Porosity was preserved in some of the grainstones by partial calcite cementation (rims, as well as scattered equant crystals and syntaxial overgrowths), which supported the framework against mechanical compaction. Dissolution of aragonitic allochems and concomitant cementation by equant calcite was prevalent in regressive shoal grainstones during repeated episodes of subaerial exposure and meteoric-water incursion as a consequence of the syn-tectonic deposition. The delta 13CV-PDB (-11.6 %o to +13.2 %o; mostly -2%o to +2 %o) suggests derivation from marine porewaters and/or dissolution of the host limestones and, in some cases, from methanogenesis of organic matter and methane oxidation. The lack of systematic differences in porosity and permeability between the limestones from the crest and the flanks of the field is attributed to the accomplishment of most diagenetic alterations before oil emplacement.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10505 - Geology

Project

—

Continuities

N - Vyzkumna aktivita podporovana z neverejnych zdroju

Publication year

2025

Confidentiality

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

Name of the periodical

MARINE AND PETROLEUM GEOLOGY

ISSN

0264-8172

e-ISSN

1873-4073

Volume of the periodical

182

Issue of the periodical within the volume

DEC

Country of publishing house

GB - UNITED KINGDOM

Number of pages

22

Pages from-to

"107607-1"-"107607-22"

UT code for WoS article

001577700800001

EID of the result in the Scopus database

2-s2.0-105016315123