A novel GIS-based tool for estimating present-day ocean reference depth using automatically processed gridded bathymetry data

作者：Jurecka Miroslawa^*; Niedzielski Tomasz; Migon Piotr

来源：Geomorphology, 2016, 260: 91-98.

DOI：10.1016/j.geomorph.2015.05.021

• GIS
• Reference depth
• Python geoprocessing
• Global bathymetry
• Oceanic crust

This paper presents a new method for computing the present-day value of the reference depth (d(r)) which is an essential input information for assessment of past sea-level changes. The method applies a novel automatic geoprocessing tool developed using Python script and ArcGIS, and uses recent data about ocean floor depth, sediment thickness, and age of oceanic crust. The procedure is multi-step and involves creation of a bathymetric dataset corrected for sediment loading and isostasy, delineation of subduction zones, computation of perpendicular sea-floor profiles, and statistical analysis of these profiles versus crust age. The analysis of site-specific situations near the subduction zones all around the world shows a number of instances where the depth of the oceanic crust stabilizes at a certain level before reaching the subduction zone, and this occurs at depths much lower than proposed in previous approaches to the reference depth issue. An analysis of Jurassic and Cretaceous oceanic lithosphere shows that the most probable interval at which the reference depth occurs is 5300-5800 m. This interval is broadly consistent with dr estimates determined using the Global Depth-Heatflow model (GDH1), but is significantly lower than dr estimates calculated on a basis of the Parsons-Sclater Model (PSM).

• 出版日期2016-5-1