marine-geophysics

GMT (Generic Mapping Tools) shell scripts building 3D perspective relief models of the Kuril-Kamchatka Trench: grdview topographic/bathymetric meshes from ETOPO relief overlaid on 2D EGM96 geoid contours, rendered at two perspective azimuths (135 and 165 degrees).

GMT (Generic Mapping Tools) shell scripts extracting and stacking serial cross-track bathymetric profiles across the Kuril-Kamchatka Trench (north and south segments) with grdtrack, plotting median stacked profiles with error envelopes over a shaded-relief basemap.

GMT and Python workflow for a quantitative morphometric typology of the twenty Pacific deep-sea trenches from GEBCO bathymetry, with the derived cross-profile database.

changing header of SAC files

Code and derived per-segment data for window-free recovery of flexural parameters at circum-Pacific trenches: a physics-informed neural inversion and the windowed least-squares baseline it is measured against.

GMT (Generic Mapping Tools) shell script converting a regularly-spaced XYZ bathymetry table directly to a NetCDF grid with xyz2grd (exact grid registration, no interpolation), then contour-mapping the result for the Kuril-Kamchatka Trench.

GMT (Generic Mapping Tools) shell scripts plotting earthquake source mechanisms over relief basemaps: focal-mechanism beachballs from GCMT moment tensors (psmeca), first-motion polarities (pspolar) and GPS/crustal velocity vectors (psvelo) for seismotectonic analysis.

Analysis code and derived segment database for morphostructural control on subduction seismicity in the Pacific Ocean: 221 trench segments parameterised morphometrically, flexurally and seismically.

Over 20 GMT (Generic Mapping Tools) shell scripts fitting polynomial and Fourier regression models to stacked bathymetric trench-profile data by weighted least squares with trend1d, comparing model orders and plotting residuals across many ocean trenches worldwide.

GMT (Generic Mapping Tools) shell scripts computing the 2D-FFT spectral coherence between marine gravity and bathymetry grids (isostasy / flexural response) with grdfft, plus multi-panel maps of bathymetry, geoid, free-air gravity and vertical gravity gradient.

GMT (Generic Mapping Tools) shell scripts demonstrating coastline-based raster clipping (pscoast clip paths) to render a colour geoid over the ocean and gray-shaded relief over masked land, for the Kuril-Kamchatka and Mariana Trenches.

GMT (Generic Mapping Tools) shell scripts producing oblique Mercator (-JOc) coastline basemaps rotated to follow ocean-trench axes / great-circle lines, with graticules and toponymy, for trench regions and a world overview.

GMT (Generic Mapping Tools) shell scripts drawing oblique Mercator (-JOc) coastline basemaps of the Kuril-Kamchatka and Mariana Trenches, with the projection axis aligned to each trench and graticules, scale bars and toponymy.

Over 25 GMT (Generic Mapping Tools) shell scripts plotting statistical histograms of bathymetric depth distributions sampled along ocean-trench cross-section profiles (mean/sigma, median/L1, LMS-mode overlays via pshistogram) with companion rose diagrams (psrose).

LaTeX (Beamer) source of the research presentation 'Deep-Sea Trenches of the Pacific Ocean: A Comparative Analysis of the Submarine Geomorphology by Data Modeling Using GMT, QGIS, Python and R' (Lemenkova), Ocean University of China, College of Marine Geo-Sciences, Qingdao, 2019.

GMT (Generic Mapping Tools) shell script building a faceted side-by-side comparison figure: two map panels contrasting gridding algorithms (xyz2grd direct conversion vs nearneighbor interpolation) of the same Kuril-Kamchatka Trench bathymetry, with shared captions and title.

GRASS GIS and GDAL shell scripts for topographical and geophysical analysis of the Japanese Archipelago from NOAA marine geophysical data and a GEBCO grid: bathymetry, geoid, gravity, magnetic anomaly, sediment thickness and slope/aspect. Figures for Lemenkova, Geomatics Environ. Eng. 2020, 14(4):25-45.

GMT shell scripts mapping the topography (GEBCO), geoid (EGM96/EGM2008) and free-air gravity (Sandwell & Smith) of the Ninety East Ridge, Indian Ocean. Figures for Lemenkova, Bulletin of Perm University. Geology 2021, 20(3):195-212.

GMT (Generic Mapping Tools) shell script drawing a global tectonic map: plate boundaries (PB2002) with rotation poles and boundary steps, GSFML seafloor fabric (fracture zones, magnetic lineation picks) and subducting-slab depth contours, on an Eckert IV equal-area projection centred on the Pacific.

AWK shell pipeline that reshapes a long GMT cross-section profile table into a wide analysis table: extracts the depth column, slices individual trench profiles by regex range, and pastes them side-by-side (12726x5 to 201x11), with mktemp temp files and cleanup.