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Geologist associated with the principal stress model of faulting represented by an Andersonian faulting regime.

A boundary between bodies with different lithologies. It can be depositional, intrusive or created by faulting. A remotely observed colour change is evidence for a candidate lithological contact, but illumination, soil and vegetation changes require independent checks.

The boundary between a mountain block and adjacent lower terrain. Its geometry records interacting tectonic uplift, faulting, erosion and deposition. A straight front, triangular facets and displaced alluvial fans together can support an active normal fault interpretation.

Probably yes in connected fractures or transiently opened pore space, especially where a transform fault admits circulating seawater; a uniform water-filled porous layer several kilometres thick is not guaranteed. Porosity and permeability of a porous medium generally decrease as cracks close or seal, while ongoing faulting can reopen pathways. Fluid can occur at high pressure and temperature, including a supercritical state; it need not resemble cold surface water.

Several complementary tests address presence and origin:

No one anomaly uniquely identifies water. Seismic velocity can also reflect cracks, composition and temperature; electrical conductivity can reflect melt or conductive minerals. Serpentinization demonstrates incorporation of water into minerals, which must be distinguished from fluid currently occupying pore space. At an oceanic transform fault, an external seawater supply is the natural first hypothesis, but isotope ratios and chemical budgets can test contributions from deep fluids rather than presuming the source. A research example of coupled deformation and hydrothermal alteration is Mass transfer and fluid flow during detachment faulting and development of an oceanic core complex, Atlantis Massif by Chiara Boschi and others; a detachment system illustrates the methods without proving identical flow at every transform fault.

For regional coverage, use stereo photogrammetry from overlapping satellite or airborne imagery, or a radar-derived digital elevation model where suitable data exist. Match the same terrain features in images taken from different known viewing positions, infer their three-dimensional positions by triangulation, and georeference and grid the result. Satellite stereo or interferometric radar can cover $10^4\mathrm{k}{\mathrm{m}}^2$ efficiently; choose pixel size and vertical precision fine enough for the fault scarps of interest, rather than assuming every regional model resolves small scarps.

InSAR topographic mapping uses the phase difference from a known viewing baseline; repeat-pass deformation work must separate that height contribution from actual motion. Vegetation, cloud, radar shadow and steep slopes can leave gaps or represent the canopy rather than bare ground.^[ref] Ground control and independent elevation checks are needed before interpreting small relief as active faulting.

The network partitions deformation into oblique horizontal displacement on the strike-slip fault and more directly north–south crustal shortening on the approximately east–west reverse fault. On the oblique strand, northeastward motion of the southeastern side relative to the northwestern side has a northward component, reducing separation in the direction of ${\sigma }_1$. On the reverse fault, northward and upward motion of the southern hanging wall shortens and thickens the crust.

Sketch north–south opposing compression arrows around the plan view, left-lateral arrows along the oblique trace, and teeth on the southern side of the reverse fault trace. A section normal to the latter shows horizontal shortening converted into tectonic uplift. Where strands meet, folding, distributed strain or subsidiary faulting can maintain displacement compatibility; a strike-slip fault terminating abruptly in undeforming rock would not. This is an interpretation involving transpression, and the map does not by itself give a unique partition of slip rates between the strands.