depthprofile

Depth profile, sometimes written as depthprofile, refers to a representation of how a given property varies with depth within a material, body of water, soil, or geological formation. It is typically plotted with depth on the vertical axis and the measured quantity on the horizontal axis, allowing visualization of gradients, interfaces, and layering.

In oceanography and limnology, depth profiles map variables such as temperature, salinity, dissolved oxygen, and nutrient concentrations with depth. These profiles reveal features like thermoclines, haloclines, and oxygen depletion zones, and they help diagnose circulation patterns and biogeochemical processes.

In soil science and environmental monitoring, depth profiles describe how properties such as pH, moisture, organic matter, nutrient availability, or contaminant concentrations change from the surface downward. They inform processes like leaching, root-zone functioning, and contaminant transport in subsurface environments.

In materials science and semiconductor manufacturing, depth profiling characterizes the composition and structure of layered materials as a function of depth. Techniques include secondary ion mass spectrometry, X-ray photoelectron spectroscopy, Auger electron spectroscopy, Rutherford backscattering, and sputter depth profiling. Depth information is often obtained by removing material layer by layer or by depth-resolved analysis, with depth calibration based on sputtering rate or known film thickness.

Applications of depth profiles include understanding diffusion and mixing processes, diagenetic or weathering histories, groundwater contamination, and the design of multilayer coatings and devices. Limitations arise from finite depth resolution, surface roughness, diffusion during measurement, and calibration uncertainties, which can blur sharp interfaces and complicate interpretation.