Marquardt, Mathias et al. (2010): A transfer function for the prediction of gas hydrate inventories in marine sediments

ODP 112
ODP 164
ODP 167
ODP 170
ODP 175
ODP 201
ODP 202
ODP 167 1014
ODP 170 1041
ODP 175 1084
ODP 201 1230
ODP 202 1233
ODP 112 685
ODP 164 995

Marquardt, Mathias
IFM-GEOMAR, Leibniz-Institut fuer Meereswissenschaften, Kiel, Germany

Hensen, Christian

Pinero, Elena

Wallmann, Klaus

Haeckel, Matthias

A transfer function for the prediction of gas hydrate inventories in marine sediments
Copernicus GmbH on behalf of the European Union, Katlenburg-Lindau, International
A simple prognostic tool for gas hydrate (GH) quantification in marine sediments is presented based on a diagenetic transport-reaction model approach. One of the most crucial factors for the application of diagenetic models is the accurate formulation of microbial degradation rates of particulate organic carbon (POC) and the coupled formation of biogenic methane. Wallmann et al. (2006) suggested a kinetic formulation considering the ageing effects of POC and accumulation of reaction products (CH (sub 4) , CO (sub 2) ) in the pore water. This model is applied to data sets of several ODP sites in order to test its general validity. Based on a thorough parameter analysis considering a wide range of environmental conditions, the POC accumulation rate (POCar in g/m (super 2) /yr) and the thickness of the gas hydrate stability zone (GHSZ in m) were identified as the most important and independent controls for biogenic GH formation. Hence, depth-integrated GH inventories in marine sediments (GHI in g of CH (sub 4) per cm (super 2) seafloor area) can be estimated as: GHI=a.POCar.GHSZ (super b) .exp(-GHSZ (super c/POCar) /d)+e with a=0.00214, b=1.234, c=-3.339, d=0.3148, e=-10.265. The transfer function gives a realistic first order approximation of the minimum GH inventory in low gas flux (LGF) systems. The overall advantage of the presented function is its simplicity compared to the application of complex numerical models, because only two easily accessible parameters need to be determined.
Coverage:Geographic coordinates:
West:-119.5853East: 13.0140

Oceanography; aliphatic hydrocarbons; alkanes; Atlantic Ocean; biogenic processes; Blake-Bahama Outer Ridge; Cape Basin; carbon; depth; East Pacific; Equatorial Pacific; gas hydrates; hydrocarbons; Leg 112; Leg 164; Leg 167; Leg 170; Leg 175; Leg 201; Leg 202; marine sediments; methane; nitrogen; North Atlantic; North Pacific; Northeast Pacific; numerical models; Ocean Drilling Program; ODP Site 1014; ODP Site 1041; ODP Site 1084; ODP Site 1230; ODP Site 1233; ODP Site 685; ODP Site 995; organic carbon; organic compounds; Pacific Ocean; particulate materials; Peru-Chile Trench; pore water; porosity; prediction; sedimentation; sedimentation rates; sediments; South Atlantic; South Pacific; Southeast Pacific; transfer functions;