Next Article in Journal
Hybrid Fixed-Point Fixed-Stress Splitting Method for Linear Poroelasticity
Next Article in Special Issue
Molecular and Isotopic Composition of Hydrate-Bound, Dissolved and Free Gases in the Amazon Deep-Sea Fan and Slope Sediments, Brazil
Previous Article in Journal
Neptunium Reactivity During Co-Precipitation and Oxidation of Fe(II)/Fe(III) (Oxyhydr)oxides
Open AccessArticle

Gas Hydrate Estimate in an Area of Deformation and High Heat Flow at the Chile Triple Junction

1
GEOMAR Helmholtz Centre for Ocean Research, Wischhofstr. 1-3, 24148 Kiel, Germany
2
Facultad de Ingeniería, Universidad Andrés Bello, Quillota 980, Viña del Mar 2531015, Chile
3
Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Av. Altamirano 1480, Valparaíso 2340000, Chile
4
Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Borgo grotta gigante 42/c, 34010 Sgonico, Italy
5
Centro de Investigación Para la Sustentabilidad (CIS), Universidad Andrés Bello, República 252, Santiago 8370134, Chile
*
Author to whom correspondence should be addressed.
Geosciences 2019, 9(1), 28; https://doi.org/10.3390/geosciences9010028
Received: 25 October 2018 / Revised: 8 December 2018 / Accepted: 31 December 2018 / Published: 8 January 2019
(This article belongs to the Special Issue Gas Hydrate: Environmental and Climate Impacts)
  |  
PDF [2757 KB, uploaded 10 January 2019]
  |     |  

Abstract

Large amounts of gas hydrate are present in marine sediments offshore Taitao Peninsula, near the Chile Triple Junction. Here, marine sediments on the forearc contain carbon that is converted to methane in a regime of very high heat flow and intense rock deformation above the downgoing oceanic spreading ridge separating the Nazca and Antarctic plates. This regime enables vigorous fluid migration. Here, we present an analysis of the spatial distribution, concentration, estimate of gas-phases (gas hydrate and free gas) and geothermal gradients in the accretionary prism, and forearc sediments offshore Taitao (45.5°–47° S). Velocity analysis of Seismic Profile RC2901-751 indicates gas hydrate concentration values <10% of the total rock volume and extremely high geothermal gradients (<190 °C·km−1). Gas hydrates are located in shallow sediments (90–280 m below the seafloor). The large amount of hydrate and free gas estimated (7.21 × 1011 m3 and 4.1 × 1010 m3; respectively), the high seismicity, the mechanically unstable nature of the sediments, and the anomalous conditions of the geothermal gradient set the stage for potentially massive releases of methane to the ocean, mainly through hydrate dissociation and/or migration directly to the seabed through faults. We conclude that the Chile Triple Junction is an important methane seepage area and should be the focus of novel geological, oceanographic, and ecological research. View Full-Text
Keywords: BSR; gas hydrate; methane; seepage; active margin; Chile Triple Junction BSR; gas hydrate; methane; seepage; active margin; Chile Triple Junction
Figures

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Villar-Muñoz, L.; Vargas-Cordero, I.; Bento, J.P.; Tinivella, U.; Fernandoy, F.; Giustiniani, M.; Behrmann, J.H.; Calderón-Díaz, S. Gas Hydrate Estimate in an Area of Deformation and High Heat Flow at the Chile Triple Junction. Geosciences 2019, 9, 28.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Geosciences EISSN 2076-3263 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top