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The Svecofennian‐Karelian‐Lapland‐Kola Transect (SVEKALAPKO) project is one of the five multidisciplinary key projects of Europrobe, a scientific program of the European Science Foundation (ESF) that studies the tectonic evolution of European continental lithosphere [Gee and Zeyen, 1996]. The SVEKALAPKO project [Hjelt and Daly, 1996] has adopted a multidisciplinary approach that uses geological, penological, and geophysical methods to unravel the evolution of the crust and lower lithosphere in three major crustal segments of the Fennoscandian Shield: the Proterozoic Svecofennian and Lapland‐Kola orogens and the intervening Archaean Karelia craton. Improved knowledge of the structure and evolution of the Fennoscandian Shield should lead to a better understanding of plate‐tectonic processes in the early history of the Earth.

Tectonic evolution of the Paleoproterozoic Vaasa migmatitic complex (VMC) in the central part of the Svecofennian accretionary orogen is deciphered using aeromagnetic and gravity maps, deep seismic and magnetotelluric profiles, and structural and metamorphic data. The VMC is a semicircular structure with migmatitic rim and granitic core composed of several subdomes. It evolved in three main tectonic events (D1-D3). The D1 event (ca. 1.89-1.88 Ga) corresponds to the stacking of supracrustal rocks and the formation of an inverted metamorphic gradient. Anatexis at LP-HT metamorphic conditions enabled the material to flow. The D2 event (ca. 1.88-1.87 Ga) corresponds to large-scale folding of the partially molten crust within an orocline. It is marked by folds with an E-W vertical axial planar foliation. The late D3 event resulted from mass redistribution owing to mechanical instabilities within the hinge of the orocline. It is marked by vertical shearing (ca. 1.87-1.85 Ga) in the marginal parts of the complex and along the granitoid subdomes. The seismic reflection profile (FIRE 3a) and magnetotelluric profiles (MT-PE and MT-B2) image large-scale D1 stacking structures within an accretionary prism. Near vertical breaks in crustal-scale reflectivity and conductivity models are interpreted as D3 shear zones. The VMC is an example of early mass and heat transfer within a collage of hot supracrustal rocks in an accretionary belt. Partial melting enhanced the flow of material, the production, and rise of magma as well as exhumation, marked by magmatic domes in the hinge of the orocline.

The marriage of several high‐quality seismic experiments in Finland over the past 30 years has shown that the saying “something old, something new, something borrowed” can result in the cost‐efficient analysis of large‐scale, three‐dimensional (3‐D) seismic structures. Standing alone, each data set gives a partial view of complex 3‐D structures. When combined, they reveal a 3‐D block structure embedded in a layered crust and enable the analysis of dynamics involved in forming stable cratonic crust. Efforts to collect large 3‐D data sets around the globe include EarthScope (funded by the U.S. National Science Foundation (NSF)), the European Science Foundations (ESF) 4‐D Topography Evolution in Europe: Uplift, Subsidence and Sea Level Change (TOPO‐EUROPE), and the European Space Agency's Gravity Field and Steady‐State Ocean Circulation Explorer (GOCE). Such endeavors are fundamental to modern crustal research. Huge emphasis is placed on collecting and archiving these data, but often only a fraction of data are used in initial studies. Fortunately, new data sets can be complemented with vintage ones (e.g., the NSF‐funded Consortium for Continental Reflection Profiling (COCORP) and ESFs European GeoTraverse (EGT), as well as continent‐wide science programs on continental evolution in Canada (LITHOPROBE), Europe (ESF‐funded EUROPROBE), and the Himalayas (NSF‐funded International Deep Profiling of Tibet and the Himalaya (INDEPTH)). Because fieldwork and archiving have already been completed for these vintage projects, new information can be extracted by new methods, with considerably less effort and funding.