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At low northern latitude, a simple induced total-field magnetic anomaly is generally asymmetric and bipolar, not a symmetric central positive peak. A compact body more magnetic than its surroundings, magnetized parallel to a northward, downward ambient field, gives its principal positive lobe on the southern side and a negative lobe toward the north. At exactly zero magnetic inclination its central anomaly reverses relative to the pole; latitude and survey orientation must therefore be included.^[ref]

For an original explicit sketch, put a dipole at depth $d$ and let $x$ increase northward. In a north–south vertical section with inducing inclination $I$, an induced magnetization parallel to the ambient field givesA geocentric-dipole approximation at latitude $20^{\circ }$ gives $I\simeq \arctan (2\tan 20^{\circ })=36.1^{\circ }$, only an illustrative field direction, not a measured local value.

For the actual crater, breccia, water and sediment may replace more magnetic basalt, giving negative magnetization contrast. In that case reverse the simple positive-body sketch: a dominant southern low and a northern high are possible even with purely induced contrasts. The magnetic sign cannot be inferred from density or from the word “crater” alone.

The supplied south–north profile has a large southern/interior negative trough and a sharp positive peak toward the northern rim. That is opposite to the simplest positive, presently induced magnetic body in question 5(d). It therefore does not justify interpreting the crater as a concentration of strongly magnetic meteorite material.

A negative magnetization contrast from replacing magnetic basalt already reverses the simple induced-body response. In addition, the target Deccan Traps can retain strong remanent magnetization whose direction differs from the present geomagnetic field; crater excavation and rim geometry then produce a strong magnetic topographic effect. Rock-magnetic measurements and forward modelling distinguish these contributions. A primary study of this crater attributes most of its anomaly to magnetized target basalts and topography, with a comparatively small contribution from the breccia and post-impact sediment.^[ref]

The curve alone is not a unique diagnosis of reversed polarity, impact-induced magnetization or a buried iron mass. The physical conclusion supported by the comparison is that a positive induced-body model is inadequate; inherited target-rock magnetization, its removal and geometry must be modelled.