Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions

Abstract Cation mole precents (XCa, XMg, and XNa) on clay minerals in a siliciclastic coastal aquifer calculated from groundwater compositions, can aid in distinguishing fluvial from marine sediments and locate the fluvial/marine transition zone. The clay‐cation compositions of two clay‐rich silicic...

Full description

Bibliographic Details
Main Authors: Cole R. Jones, Regina M. Capuano
Format: Article
Language:English
Published: Wiley 2023-02-01
Series:Geochemistry, Geophysics, Geosystems
Subjects:
Online Access:https://doi.org/10.1029/2022GC010601
_version_ 1797638087539425280
author Cole R. Jones
Regina M. Capuano
author_facet Cole R. Jones
Regina M. Capuano
author_sort Cole R. Jones
collection DOAJ
description Abstract Cation mole precents (XCa, XMg, and XNa) on clay minerals in a siliciclastic coastal aquifer calculated from groundwater compositions, can aid in distinguishing fluvial from marine sediments and locate the fluvial/marine transition zone. The clay‐cation compositions of two clay‐rich siliciclastic coastal aquifers calculated from the composition of the groundwater were compared to the location of fluvial, fluvial‐marine transition and marine environments identified by traditional core, well log and paleontological analyses. The traditionally defined fluvial depositional environment is distinguished by clays with low XNa < 8% (for 92% of the samples) and high XCa from 55% to 98% with the remainder XMg. In comparison, the traditionally defined marine depositional environment is distinguished by clays with higher XNa > 8.0% (for 86% of the samples) and lower XCa ranging from 5% to 39% with the remainder XMg. The traditionally defined fluvial/marine transition zone has values overlapping the fluvial and marine end members, with 59% with XNa < 8% (fluvial) and 41% with XNa > 8% (marine), and XCa ranging from 45% to 98% with the remainder XMg. Calculations support that the excess Na (XNa > 8%) on marine clays can be retained for 10s of millions of years despite flushing with meteoric water, because of the high clay content in marine sediments. The calculated cation composition of clays deposited from river water are XNa < 8%. In contrast XNa 8%–54% is possible for seawater equilibrated clays supporting that the values found in the different depositional zones are possible. Calculated cation compositions might supplement traditional stratigraphic interpretations in distinguishing fluvial/marine depositional environments.
first_indexed 2024-03-11T12:58:37Z
format Article
id doaj.art-80c37437455c4f32b875fad0a5810656
institution Directory Open Access Journal
issn 1525-2027
language English
last_indexed 2024-03-11T12:58:37Z
publishDate 2023-02-01
publisher Wiley
record_format Article
series Geochemistry, Geophysics, Geosystems
spelling doaj.art-80c37437455c4f32b875fad0a58106562023-11-03T16:55:39ZengWileyGeochemistry, Geophysics, Geosystems1525-20272023-02-01242n/an/a10.1029/2022GC010601Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation CompositionsCole R. Jones0Regina M. Capuano1Department of Earth and Atmospheric Sciences University of Houston Houston TX USADepartment of Earth and Atmospheric Sciences University of Houston Houston TX USAAbstract Cation mole precents (XCa, XMg, and XNa) on clay minerals in a siliciclastic coastal aquifer calculated from groundwater compositions, can aid in distinguishing fluvial from marine sediments and locate the fluvial/marine transition zone. The clay‐cation compositions of two clay‐rich siliciclastic coastal aquifers calculated from the composition of the groundwater were compared to the location of fluvial, fluvial‐marine transition and marine environments identified by traditional core, well log and paleontological analyses. The traditionally defined fluvial depositional environment is distinguished by clays with low XNa < 8% (for 92% of the samples) and high XCa from 55% to 98% with the remainder XMg. In comparison, the traditionally defined marine depositional environment is distinguished by clays with higher XNa > 8.0% (for 86% of the samples) and lower XCa ranging from 5% to 39% with the remainder XMg. The traditionally defined fluvial/marine transition zone has values overlapping the fluvial and marine end members, with 59% with XNa < 8% (fluvial) and 41% with XNa > 8% (marine), and XCa ranging from 45% to 98% with the remainder XMg. Calculations support that the excess Na (XNa > 8%) on marine clays can be retained for 10s of millions of years despite flushing with meteoric water, because of the high clay content in marine sediments. The calculated cation composition of clays deposited from river water are XNa < 8%. In contrast XNa 8%–54% is possible for seawater equilibrated clays supporting that the values found in the different depositional zones are possible. Calculated cation compositions might supplement traditional stratigraphic interpretations in distinguishing fluvial/marine depositional environments.https://doi.org/10.1029/2022GC010601groundwaterclay compositionfluvial marinedepositional environmentcoastal sedimentscation exchange
spellingShingle Cole R. Jones
Regina M. Capuano
Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
Geochemistry, Geophysics, Geosystems
groundwater
clay composition
fluvial marine
depositional environment
coastal sediments
cation exchange
title Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
title_full Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
title_fullStr Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
title_full_unstemmed Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
title_short Fluvial and Marine Depositional Environments Determined From Groundwater Chemistry and Calculated Clay‐Cation Compositions
title_sort fluvial and marine depositional environments determined from groundwater chemistry and calculated clay cation compositions
topic groundwater
clay composition
fluvial marine
depositional environment
coastal sediments
cation exchange
url https://doi.org/10.1029/2022GC010601
work_keys_str_mv AT colerjones fluvialandmarinedepositionalenvironmentsdeterminedfromgroundwaterchemistryandcalculatedclaycationcompositions
AT reginamcapuano fluvialandmarinedepositionalenvironmentsdeterminedfromgroundwaterchemistryandcalculatedclaycationcompositions