Raster Visualization
A completed spatial analysis appears in the sidebar as a child of the aquifer it was run on. Clicking the analysis loads the raster — a sequence of color-mapped overlay frames — onto the map, alongside a set of playback controls, color-ramp options, and a summary statistics view in the chart panel. This page covers how to drive the visualization and how to read what it's showing.
Loading a raster activates the raster controls panel attached to the map and populates the chart panel with additional tabs (Storage Change, Raster Statistics, and Cross Section, when appropriate). Clicking the raster again in the sidebar unloads it and returns the map to the plain well-marker view. Only one raster can be loaded at a time; clicking a different raster swaps in the new one.
Color Mapping
Six color ramps are available for the raster overlay, selectable from a dropdown in the raster controls panel. Each ramp is implemented as a 64-step lookup table so transitions are visually smooth across the full value range.
| Ramp | Character | Suited to |
|---|---|---|
| BGYR (default) | Blue → Green → Yellow → Red | Sequential data where low-to-high direction matters |
| Viridis | Purple → Green → Yellow | General-purpose; colorblind-friendly |
| Plasma | Purple → Orange → Yellow | High-contrast sequential, emphasizes high end |
| Turbo | Red → Yellow → Green → Cyan → Blue | Spectral, preserves fine detail at cost of perceptual linearity |
| Inferno | Black → Red → Yellow → White | Works well on dark basemaps |
| Blues | Light blue → Dark blue | Monochromatic, water-themed |
BGYR is the default because the blue-to-red direction is widely associated with low-to-high values in hydrogeologic figures. Viridis is a stronger choice for figures intended for publication or for audiences that include colorblind readers, since it's perceptually uniform and readable across the common forms of colorblindness.
The color scale is computed automatically from the 2nd-to-98th percentile of all values across all raster frames. This percentile clipping keeps a handful of extreme values — often generated by extrapolation in data-sparse areas — from compressing the visible color range into the middle of the ramp. The colorbar alongside the map shows the current value-to-color mapping.
Contour Lines
Toggling Contour Lines in the raster controls overlays a set of isolines on the raster surface. The isolines are computed with a marching-squares algorithm at eight evenly-spaced levels across the value range. Contours serve a diagnostic purpose that pure color maps don't: closely spaced lines indicate steep gradients, widely spaced lines indicate gentle slopes, and closed loops mark local highs and lows. For water-table work, contour lines effectively function as a potentiometric map — the gradient direction reads as the perpendicular to the contours at every point.
Contour lines track the animation, so scrubbing through frames shows how the isoline geometry evolves over time. A pumping cone that's deepening shows up as contours tightening around the pumping center; a recharge pulse shows up as contours spreading outward from a recharge area.
Animation Playback
A raster generated with multiple time frames — anything with an output window longer than the frame interval — can be animated through time.
The Play button starts the animation; frames advance at roughly 500 ms intervals and the loop stops at the last frame rather than wrapping back to the first automatically. Pause halts the animation and keeps the current frame displayed. The frame slider lets you scrub to any frame directly, which is often the faster way to navigate than playing through and pausing on a specific date. The current date is displayed above the slider so you always know which moment the overlay represents.
Scrubbing the slider is also the primary way to coordinate the different chart tabs with the map. The storage-change and raster-statistics charts, described below, both show a vertical reference line at the current frame's date, and cross-section profiles update to reflect whichever frame you've scrubbed to.
Cursor Tooltip
Hovering over the raster shows a tooltip with the interpolated value at the cursor location, rounded to one decimal place. The tooltip appears only over cells inside the aquifer boundary; pixels outside the polygon mask show nothing. This is the fastest way to read specific values at arbitrary locations — well locations, features visible in the basemap, or simply anywhere the surface's behavior looks worth noting.
Raster Statistics Chart
When a raster is loaded, a Raster Statistics tab becomes available in the chart panel. This chart plots the distribution of well values at each frame time — not the interpolated grid values, but the per-frame distribution of the actual well data that went into the interpolation. It's the right view for answering questions like "how has the typical well's value changed over this period?" or "is the variability across the aquifer growing or shrinking?"
The chart's default display shows a solid blue mean line with a lighter blue ±1 standard deviation band shaded around it, which gives an immediate read on both central tendency and dispersion across frames. A settings icon in the top-right corner toggles additional overlays: the median as a purple dashed line (useful when the data is skewed and the mean is pulled by outliers), the interquartile range (P25–P75) as a teal band, and the min–max envelope as a wider orange band that shows the total spread at each frame.
The six statistics computed at each frame are: mean, standard deviation, median, 25th percentile, 75th percentile, minimum, maximum, and the well count. Hovering over the chart at any x-axis position shows all of these for the frame under the cursor, along with the date and the number of wells with qualifying data at that frame.
A vertical red line on the statistics chart tracks the animation's current frame, keeping it synchronized with the map overlay and any other chart tabs. Scrubbing the raster slider moves this reference line in real time, which is useful when you want to see how the raster at a specific time relates to the aquifer-wide statistics at that same time.
Managing Rasters
Right-clicking a raster in the sidebar opens a context menu with three options. Get Info opens a modal summarizing the analysis parameters — the interpolation method and its options, the date range and frame interval, the resolution, the number of qualifying wells, and the creation timestamp. This is the reference view for remembering exactly how a raster was built, which matters when you have several rasters for the same aquifer and need to recall which one used which method.
Rename changes the raster's display label in the sidebar but leaves the underlying file on disk unchanged. This is purely cosmetic; it's useful for tagging rasters with shorter or more descriptive names after the fact.
Delete removes the raster from disk, with a confirmation dialog. Deleting a raster also clears it from any sidebar, map, or chart view it's currently loaded in.