Baltica data makes it difficult to locate the margin in the Arctic. Ordovician faunas indicate that most of Svalbard, including Bjørnøya, was part of Laurentia, but Franz Josef Land and Kvitøya (an eastern island of the Svalbard archipelago) most likely became part of Baltica in the Timanide Orogeny. The Taymyr Peninsula, in contrast, never was part of Baltica: southern Taymyr was part of Siberia whilst northern Taymyr and the Severnaya Zemlya archipelago were part of the independent Kara Terrane in the early Palaeozoic. The eastern margin, the Uralide orogen, extends from the Arctic Novaya Zemlya archipelago to the Aral Sea. The
Novaya Zemlya Novaya Zemlya. The launch rocket was subsequently deployed to Cuba. 1963 saw the implementation of the Limited Test Ban Treaty which banned most atmospheric nuclear tests. The largest underground test in Novaya Zemlya took place on September 12, 1973, involving four nuclear devices of 4.2 megatons total yield. Although far smaller in blast power than the Tsar Bomba and other atmospheric tests, the confinement of the blasts underground led to pressures rivaling natural earthquakes. In the case of the September 12, 1973, test, a seismic magnitude of 6.97 on the Richter Scale was reached, setting off an 80 million ton