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芬诺罗拉(FENNOLORA)计划—1979年的芬诺斯堪的亚长测线地震计划,它的主要目的是确定在芬诺斯堪的亚地盾下方400多公里深度下的下部岩石圈和上地幔的结构。本研究中,瑞典南部各台站记录的三个爆炸点的资料被用来导出延伸600多公里的一个二维岩石圈结构模型。这三个爆炸点,一个在德国北部(剖面WN),两个在瑞典南部,相距300km(剖面BN和CS)。从北到南,这个剖面通过瑞芬构造(Svecofennides)、斯玛兰德-伐姆兰德(Smaland-Varmland)花岗岩带、不整合地覆盖在芬诺斯堪的亚地盾上的古生代岩石,经波罗的海(这里没有台站)进入德国北部的加里东构造区,在德国北部有一个爆炸点,但没有台站。这三个记录剖面图的解释是基于二维射线跟踪的方法,这种方法包括渐近射线理论综合地震图的计算。由于没有从德国的爆炸点到瑞典南部台站0～150km内的数据,因此,得不到这一地区详细的地壳结构图。测得地壳的厚度为32km。在大约50km深处,速度从8.00km/s迅速增大到8.35km/s,而下边是一个一直延伸到70km深度的低速带。对瑞典南部的相遇剖面BN和CS,情况完全不同,解释结果表明,地壳厚度与剖面北段相差大约12km。此段的莫霍面比较深,下地壳较厚,且有一个壳-幔过渡带,而不是速度的迅速增大。在这个相遇剖面的南段,有一个范围有限的地壳低速区。这一解释结果最重要的方面,是指出了瑞典南部两个爆炸点之间,地壳结构的变化出现在小于几十公里的、横向宽度有限的一个过渡区内。我们认为,模型的这个过渡区是一个主要的岩石圈边界,它与斯玛兰德-伐姆兰德花岗岩带与瑞芬构造的交接有关。
FENNOLORA PROGRAM - The Finno Scandinavian long-line survey of earthquakes in 1979, whose main purpose was to identify the lower lithosphere above and above the depth of more than 400 km beneath the Finn-Scandinavian shield Structure of the mantle. In this study, the data of the three explosion points recorded at various stations in southern Sweden were used to derive a two-dimensional lithospheric structural model extending over 600 kilometers. The three explosions, one in northern Germany (section WN) and two in southern Sweden, are 300 km (section BN and CS). From north to south, this section passes through the Svecofennides, Smaland-Varmland granite belts unconformably over the Paleozoic rocks of the Finn Scandinavian shield, The Baltic Sea (where there is no station) enters the Caledonian tectonic zone in northern Germany, with an explosion point in northern Germany but no stations. The interpretation of these three recorded profiles is based on a two-dimensional ray-tracing method that includes the computation of synthetic seismograms using asymptotic ray theory. Because there is no data from the German explosion point to 0-150 km from southern Sweden, no detailed crustal structure map of this area is available. The measured crust thickness is 32km. At a depth of about 50 km, the speed rapidly increases from 8.00 km / s to 8.35 km / s, while the lower part is a low speed zone that extends to a depth of 70 km. The situation is completely different for the encounter profiles BN and CS in southern Sweden, and interpretation shows that the crustal thickness differs from the northern section of the profile by about 12 km. This section of the Moho is relatively deep, the lower crust thick, and there is a crust-mantle transition zone, rather than the rapid increase in speed. In the southern section of this encounter profile, there is a limited area of low crustal velocity. The most important aspect of this interpretation is the indication of the change in crustal structure between two explosions in southern Sweden in a transition zone of less than tens of kilometers of limited lateral width. We believe that this transitional area of the model is a major lithospheric boundary associated with the handover of the Reimafen structure between the Simarande-Vulland granite belt.