HISTORY OF SEISMOLOGY IN CROATIA

The work of Andrija Mohorovičić (1857–1936) had a large impact on the development of seismology, both in Croatia and world-wide. This paper presents a chronological survey of the development of seismology in Croatia providing context for the discovery of the Mohorovičić discontinuity in 1910. The development of early Croatian seismology was strongly influenced by advances in the field made in both Europe and world-wide. It also was influenced by several strong earthquakes that occurred within its territory, most notably the 1880 Zagreb earthquake, and the 1909 Kupa Valley (Pokupsko) earthquake. By studying the seismograms from the Kupa Valley earthquake, Mohorovičić was able to prove the existence of the boundary layer between the Earth's crust and the mantle (the Mohorovičić discontinuity). After Mohorovičić retired in 1921, seismological research in Croatia lost much of it's momentum, and for 20 years no seismological papers were published. After World War II, the Geophysical Institute was incorporated into the Faculty of Science of the University of Zagreb, and seismologists became active once more. Beginning in the second half of the twentieth century, the scientific interests of Croatian seismologists broadened, and international cooperation intensified. During that time, the number of active seismologists in Croatia varied, but never exceeded twelve, all of whom were affiliated with the Department of Geophysics of the Faculty of Science at the University of Zagreb. This small seismological community bore the responsibility of maintaining high standards in seismological research and education, and of keeping Croatian seismology visible in the world of geophysical sciences.

A sismicidade no Curso de Sismologia (1970) de Frederico Machado e seis cartas históricas de isossistas com interesse para o Ensino de Ciências

Resumo Nos documentos curriculares portugueses em vigor para a disciplina de Ciências Naturais, 7.o ano de escolaridade, há uma orientação no sentido da exploração e discussão de cartas de isossistas relativas a sismos com efeitos no território nacional. Neste trabalho incluímos alguns apontamentos históricos sobre o conceito de intensidade sísmica, a qual permite a medição de um terramoto sem recurso a instrumentos, e apresentamos seis cartas de isossistas que constam no Curso de Sismologia (1970) de Frederico Machado. Para cada carta de isossistas analisámos as fontes utilizadas pelo autor e produzimos uma reflexão com sugestões para exploração em contexto didático. Verificámos que estas cartas são representativas da sismicidade no território português e constituem uma oportunidade para explorar o conceito de intensidade sísmica e corresponder às orientações curriculares (ensino básico) para este tema. Palavras-chave: História da Sismologia, intensidade sísmica, cartas de isossistas Abstract In current portuguese curricular documents for the Natural Sciences subject, 7th grade, there is an orientation towards exploring and discussing isoseismal maps related to earthquakes with effects in the portuguese territory. In this work we include some historical notes about the concept of seismic intensity, which allows the measurement of an earthquake without the use of instruments, and we present six isoseismals maps that are included in Curso de Sismologia (1970) by Frederico Machado. For each isoseismal map we analyzed the sources used by the author and we produced a reflection with suggestions for didactic exploration. We found that these maps are representative of the seismicity in the Portuguese territory and provide an opportunity to explore the concept of seismic intensity and to meet the curricular orientations (basic education) for this theme. Keywords: History of Seismology, seismic intensity, isoseismal maps