The adiabatic acceleration of ions due to magnetic field line curvature and the consequent signatures at the precipitation into the ionosphere are examined by means of single-particle trajectory codes. It is shown that in disturbed times the quatorial geometry of the geomagnetic field ''naturally'' yields bandlik structures (characterized by a decrease of the mean energy with decreasing latitude) in the low-latitude precipitation pattern. Particularly, it is demonstrated that double traces are possibly produced over the auroral zone, owing to prolonged earthward convection of distant populations. Arguments based on particle time of flight and convection time scale bring out the necessity of a narrowly localized region of enhanced magnetotail stretch as well as limited peak energies for the particles (below a few keV for protons) in order to produce such multiple features. ¿American Geophysical Union 1991