In:
Science, American Association for the Advancement of Science (AAAS), Vol. 348, No. 6233 ( 2015-04-24), p. 428-431
Abstract:
Methane is a key component in the global carbon cycle, with a wide range of anthropogenic and natural sources. Although isotopic compositions of methane have traditionally aided source identification, the abundance of its multiply substituted “clumped” isotopologues (for example, 13 CH 3 D) has recently emerged as a proxy for determining methane-formation temperatures. However, the effect of biological processes on methane’s clumped isotopologue signature is poorly constrained. We show that methanogenesis proceeding at relatively high rates in cattle, surface environments, and laboratory cultures exerts kinetic control on 13 CH 3 D abundances and results in anomalously elevated formation-temperature estimates. We demonstrate quantitatively that H 2 availability accounts for this effect. Clumped methane thermometry can therefore provide constraints on the generation of methane in diverse settings, including continental serpentinization sites and ancient, deep groundwaters.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.aaa4326
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2015
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11