Summary
The postglacial Stuoragurra Fault (SF) lies within the regional Mierujav'ri- Sværholt Fault Zone which is located in the extensive Proterozoic terrain of inner Finnmark. To explore the SF at depth, 135 m of core-drilling was located between two previous percussion drillholes. More detailed information has been acquired from the coredrilling as compared with the previous drilling. The location of the main fault zones from the core-drilling is consistent with the results from the geophysical measurements. The two uppermost zones are coinci- ding with 2-3 m wide zones of brecciation. The postglacial fault coincides with the lowermost of these zones and is composed of several thin (a few cm wide) zones of fault gouge within a 1.5 metre wide zone at a depth of 37 metres. We can conclude that the postulated listric shape of the fault is most likely to be the corrrected model. The annual average changes in elevation of benchmarks based on precision levelling in 1954 and later in 1975 along the old road from Alta to Kautokeino have shown a significant deviation from the general postglacial upheaval of Fennoscandia. Instead of an increasing uplift from 2 mm/year in Alta to 5 mm/year in Kautokeino as is generally indicated on land upheaval maps of Fennoscandia, a subsidence of the inland area was observed. During Quaternary geological mapping in the Iesjav'ri area one submerged shoreline has been observed at the southern margin of this lake. The shoreline is located roughly a few dm below the present water-level, and we think that this indicates that a vertical crustal movement with a N-S gradient opposite to that of the general postglacial rebound has occured during the last few hundred years. Relevelling of the profile of 1954 and 1975, however, did not reproduce this pattern. We therefore recommend that a system- atic mapping of the shorelines around Iesjav'ri should be carrie
