Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf
Carbon cycling is an important but poorly understood process on passive continental margins. In this study, we use the ionic and stable isotopic composition of interstitial waters and the petrology, mineralogy, and stable isotopic composition of authigenic carbonates collected from Ocean Drilling Pr...
Main Authors: | , , , |
---|---|
Format: | Dataset |
Language: | English |
Published: |
PANGAEA
2002
|
Subjects: | |
Online Access: | https://doi.pangaea.de/10.1594/PANGAEA.740060 https://doi.org/10.1594/PANGAEA.740060 |
id |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.740060 |
---|---|
record_format |
openpolar |
spelling |
ftpangaea:oai:pangaea.de:doi:10.1594/PANGAEA.740060 2023-05-15T17:37:02+02:00 Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf Malone, Mitchell J Claypool, George E Martin, Jonathan B Dickens, Gerald Roy MEDIAN LATITUDE: 39.373986 * MEDIAN LONGITUDE: -72.709540 * SOUTH-BOUND LATITUDE: 39.365610 * WEST-BOUND LONGITUDE: -72.724500 * NORTH-BOUND LATITUDE: 39.382361 * EAST-BOUND LONGITUDE: -72.694580 * DATE/TIME START: 1997-06-23T00:00:00 * DATE/TIME END: 1997-06-29T00:00:00 2002-06-22 application/zip, 2 datasets https://doi.pangaea.de/10.1594/PANGAEA.740060 https://doi.org/10.1594/PANGAEA.740060 en eng PANGAEA https://doi.pangaea.de/10.1594/PANGAEA.740060 https://doi.org/10.1594/PANGAEA.740060 CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess CC-BY Supplement to: Malone, Mitchell J; Claypool, George E; Martin, Jonathan B; Dickens, Gerald Roy (2002): Variable methane fluxes in shallow marine systems over geologic time. The composition and origin of pore waters and authigenic carbonates on the New Jersey shelf. Marine Geology, 189(3-4), 175-196, https://doi.org/10.1016/S0025-3227(02)00474-7 174-1071 174-1072 174-1072A COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg174A North Atlantic Ocean Ocean Drilling Program ODP Dataset 2002 ftpangaea https://doi.org/10.1594/PANGAEA.740060 https://doi.org/10.1016/S0025-3227(02)00474-7 2023-01-20T07:31:49Z Carbon cycling is an important but poorly understood process on passive continental margins. In this study, we use the ionic and stable isotopic composition of interstitial waters and the petrology, mineralogy, and stable isotopic composition of authigenic carbonates collected from Ocean Drilling Program (ODP) Leg 174A (Sites 1071 and 1072) to constrain the origin of the carbonates and the evolution of methane on the outer New Jersey shelf. The pore fluids of the New Jersey continental shelf are characterized by (1) a fresh-brackish water plume, and (2) organic matter degradation reactions, which proceed through sulfate reduction. However, only minor methanogenesis occurs. The oxygen isotopic composition of the pore fluids supports a meteoric origin of the low salinity fluids. Authigenic carbonates are found in nodules, thin (~1-cm) layers, and carbonate cemented pavements. Siderite is the most common authigenic carbonate, followed by dolomite and calcite. The oxygen isotopic composition of the authigenic carbonates, i.e. 1.3-6.5 per mil PeeDee Belemnite (PDB), indicates an origin in marine pore fluids. The carbon isotopic composition of dolomite cements range from -16.4 to -8.8 per mil PDB, consistent with formation within the zone of sulfate reduction. Siderite d13C values show a greater range (-17.67-16.4 per mil), but are largely positive (mean=2.8 per mil) and are interpreted to have formed throughout the zone of methanogenesis. In contrast, calcite d13C values are highly negative (as low as -41.7 per mil)and must have formed from waters with a large component of dissolved inorganic carbon derived from methane oxidation. Pore water data show that despite complete sulfate reduction, methanogenesis appears not to be an important process presently occurring in the upper 400 m of the outer New Jersey shelf. In contrast, the carbon isotopic composition of the siderites and calcites document an active methanogenic zone during their formation. The methane may have been either oxidized or vented from shelf ... Dataset North Atlantic PANGAEA - Data Publisher for Earth & Environmental Science ENVELOPE(-72.724500,-72.694580,39.382361,39.365610) |
institution |
Open Polar |
collection |
PANGAEA - Data Publisher for Earth & Environmental Science |
op_collection_id |
ftpangaea |
language |
English |
topic |
174-1071 174-1072 174-1072A COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg174A North Atlantic Ocean Ocean Drilling Program ODP |
spellingShingle |
174-1071 174-1072 174-1072A COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg174A North Atlantic Ocean Ocean Drilling Program ODP Malone, Mitchell J Claypool, George E Martin, Jonathan B Dickens, Gerald Roy Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
topic_facet |
174-1071 174-1072 174-1072A COMPCORE Composite Core DRILL Drilling/drill rig Joides Resolution Leg174A North Atlantic Ocean Ocean Drilling Program ODP |
description |
Carbon cycling is an important but poorly understood process on passive continental margins. In this study, we use the ionic and stable isotopic composition of interstitial waters and the petrology, mineralogy, and stable isotopic composition of authigenic carbonates collected from Ocean Drilling Program (ODP) Leg 174A (Sites 1071 and 1072) to constrain the origin of the carbonates and the evolution of methane on the outer New Jersey shelf. The pore fluids of the New Jersey continental shelf are characterized by (1) a fresh-brackish water plume, and (2) organic matter degradation reactions, which proceed through sulfate reduction. However, only minor methanogenesis occurs. The oxygen isotopic composition of the pore fluids supports a meteoric origin of the low salinity fluids. Authigenic carbonates are found in nodules, thin (~1-cm) layers, and carbonate cemented pavements. Siderite is the most common authigenic carbonate, followed by dolomite and calcite. The oxygen isotopic composition of the authigenic carbonates, i.e. 1.3-6.5 per mil PeeDee Belemnite (PDB), indicates an origin in marine pore fluids. The carbon isotopic composition of dolomite cements range from -16.4 to -8.8 per mil PDB, consistent with formation within the zone of sulfate reduction. Siderite d13C values show a greater range (-17.67-16.4 per mil), but are largely positive (mean=2.8 per mil) and are interpreted to have formed throughout the zone of methanogenesis. In contrast, calcite d13C values are highly negative (as low as -41.7 per mil)and must have formed from waters with a large component of dissolved inorganic carbon derived from methane oxidation. Pore water data show that despite complete sulfate reduction, methanogenesis appears not to be an important process presently occurring in the upper 400 m of the outer New Jersey shelf. In contrast, the carbon isotopic composition of the siderites and calcites document an active methanogenic zone during their formation. The methane may have been either oxidized or vented from shelf ... |
format |
Dataset |
author |
Malone, Mitchell J Claypool, George E Martin, Jonathan B Dickens, Gerald Roy |
author_facet |
Malone, Mitchell J Claypool, George E Martin, Jonathan B Dickens, Gerald Roy |
author_sort |
Malone, Mitchell J |
title |
Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
title_short |
Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
title_full |
Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
title_fullStr |
Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
title_full_unstemmed |
Stable carbon and oxygen isotope record of diagenetic carbonates from the New Jersey shelf |
title_sort |
stable carbon and oxygen isotope record of diagenetic carbonates from the new jersey shelf |
publisher |
PANGAEA |
publishDate |
2002 |
url |
https://doi.pangaea.de/10.1594/PANGAEA.740060 https://doi.org/10.1594/PANGAEA.740060 |
op_coverage |
MEDIAN LATITUDE: 39.373986 * MEDIAN LONGITUDE: -72.709540 * SOUTH-BOUND LATITUDE: 39.365610 * WEST-BOUND LONGITUDE: -72.724500 * NORTH-BOUND LATITUDE: 39.382361 * EAST-BOUND LONGITUDE: -72.694580 * DATE/TIME START: 1997-06-23T00:00:00 * DATE/TIME END: 1997-06-29T00:00:00 |
long_lat |
ENVELOPE(-72.724500,-72.694580,39.382361,39.365610) |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Supplement to: Malone, Mitchell J; Claypool, George E; Martin, Jonathan B; Dickens, Gerald Roy (2002): Variable methane fluxes in shallow marine systems over geologic time. The composition and origin of pore waters and authigenic carbonates on the New Jersey shelf. Marine Geology, 189(3-4), 175-196, https://doi.org/10.1016/S0025-3227(02)00474-7 |
op_relation |
https://doi.pangaea.de/10.1594/PANGAEA.740060 https://doi.org/10.1594/PANGAEA.740060 |
op_rights |
CC-BY-3.0: Creative Commons Attribution 3.0 Unported Access constraints: unrestricted info:eu-repo/semantics/openAccess |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1594/PANGAEA.740060 https://doi.org/10.1016/S0025-3227(02)00474-7 |
_version_ |
1766136747808260096 |