FN Archimer Export Format
PT J
TI Defining active, inactive, and extinct seafloor massive sulfide deposits
BT 
AF Jamieson, J.W.
   Gartman, A.
AS 1:1;2:2;
FF 1:;2:;
C1 Department of Earth Sciences, Memorial University of Newfoundland, St. John's, NL, A1B 3X5, Canada
   U.S. Geological Survey Pacific Coastal and Marine Science Center, 2885 Mission Street, Santa Cruz, CA, 95060, USA
C2 UNIV MEM NEWFOUNDLAND, CANADA
   US GEOL SURVEY, USA
IF 2.453
TC 24
UR https://archimer.ifremer.fr/doc/00618/72972/72039.pdf
LA English
DT Article
CR SERPENTINE
BO Pourquoi pas ?
DE ;Hydrothermal systems;Seafloor massive sulfide deposits;Inactive deposits;Seafloor mining
AB Hydrothermal activity results in the formation of hydrothermal mineral deposits, including seafloor massive sulfide deposits, at oceanic spreading ridges, arcs, and back-arcs. As hydrothermal systems age, the mineral deposits eventually become severed from the heat source and fluid-flow pathways responsible for their formation and become extinct. The timescales and processes by which this cessation of activity occurs, and the resultant distinction between hydrothermally active and inactive deposits has recently taken on policy implications related to the potential issuance of exploitation leases for seafloor massive sulfide deposits by the International Seabed Authority in Areas Beyond National Jurisdiction. Here, we discuss the scientific rationale behind designating hydrothermal systems as active, inactive, or extinct, with the aim of applying a scientific underpinning to ongoing policy discussions, which often lack a common set of criteria and use the same descriptions for opposing phenomena. We apply the simple definition that active vent fields currently exhibit fluid flow above ambient seawater temperatures, inactive vent fields are not currently exhibiting fluid flow but may potentially become active again, and extinct vent fields are not expected to become active again. We suggest these terms can only be correctly applied at the vent field scale and define a vent field as a geologically continuous entity that may include both actively and formerly venting hydrothermal deposits. Finally, we propose criteria and techniques for determining activity and reasonably bounding the extent of a vent field for classification purposes. 
PY 2020
PD JUN
SO Marine Policy
SN 0308-597X
PU Elsevier BV
VL 117
UT 000541263200067
DI 10.1016/j.marpol.2020.103926
ID 72972
ER

EF