TIME-CORRELATION BY PALEOMAGNETISM OF THE 1631 ERUPTION OF MOUNT VESUVIUS - VOLCANOLOGICAL AND VOLCANIC HAZARD IMPLICATIONS

被引:22
作者
CARRACEDO, JC
PRINCIPE, C
ROSI, M
SOLER, V
机构
[1] CNR,IST GEOCHRONOL & GEOCHIM ISOTOP,I-57127 PISA,ITALY
[2] UNIV PISA,DIPARTIMENTO SCI TERRA,I-56100 PISA,ITALY
关键词
D O I
10.1016/0377-0273(93)90108-4
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The 1631 eruption of Mount Vesuvius was the most destructive episode in the recent volcanic history of Vesuvius and the last in which large pyroclastic flows were emitted. The controversy about whether lava flows were also generated in this eruption, as sustained in the mapping by Le Hon (1866) and by the interpretation by some authors (Burri et al., 1975; Rolandi et al., 1991) of eyewitness accounts, is important not only for a better understanding of the eruption but also for the implications in the prediction of volcanic hazards of this volcano, set in an overpopulated area with more than 3 million people potentially at risk. Short-period palaeomagnetic techniques (secular variation curve) have been applied to correlate lava flows interpreted as produced in the event of 1631 with the pyroclastic flow of this same eruption and other lava flows unquestionably emitted prior to this eruptive event. The model that best fits the results obtained suggests that the presumed 1631 lava flows were not the result of a single eruptive event but were, in fact, produced by several different eruptions. These lava flows also have a better palaeomagnetic correlation with the medieval lava flows than with the pyroclastic flow of 1631, whose juvenile pumice clasts have a well-defined single component magnetization that fits in the expected corresponding position of the secular variation curve for that age. The palaeomagnetic characteristics of the 1631 pyroclastic flow are compatible with a ''hot'' depositional temperature (apparently above the Curie point of magnetite, 585 degrees C) for the juvenile pumice fragments (magmatic fraction) and a ''cold'' deposition for the non-magmatic fraction. This suggests the lack of thermal equilibration during transport of the larger clasts, probably due to the short distance travelled by the pyroclastic flows. The main volcanological and volcanic hazard issues of this work are that the 1631 event was entirely explosive and that pyroclastic flow activity played a major role in the eruption. Before 1631 Vesuvius remained for about five centuries in a state of quiescence. If the present period of repose continues for decades or centuries it is increasingly likely that the next eruption will be a highly dangerous explosive event similar to that of 1631.
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页码:203 / 209
页数:7
相关论文
共 19 条
[1]   TEMPERATURE ESTIMATION OF PYROCLASTIC DEPOSITS BY NATURAL REMANENT MAGNETISM [J].
ARAMAKI, S ;
AKIMOTO, SI .
AMERICAN JOURNAL OF SCIENCE, 1957, 255 (09) :619-627
[2]  
Arno V., 1987, QUAD RIC SCI, V114, P53
[3]  
Bauer L. A., 1895, PHYS REV, V2, P455
[4]  
Bauer L. A., 1896, PHYS REV, V3, P34
[5]   SECULAR VARIATION IN ITALY FROM HISTORICAL GEOMAGNETIC-FIELD MEASUREMENTS [J].
CAFARELLA, L ;
DESANTIS, A ;
MELONI, A .
PHYSICS OF THE EARTH AND PLANETARY INTERIORS, 1992, 73 (3-4) :206-221
[6]  
Di Girolamo P., 1975, REND SOC ITAL MINERA, V30, P705
[7]   DISPERSION ON A SPHERE [J].
FISHER, R .
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES, 1953, 217 (1130) :295-305
[8]   ARCHAEOMAGNETIC SECULAR VARIATION RECORD OF MOUNT VESUVIUS [J].
HOYE, GS .
NATURE, 1981, 291 (5812) :216-218
[9]   PALEOMAGNETIC DETERMINATION OF EMPLACEMENT TEMPERATURE OF VESUVIUS AD 79 PYROCLASTIC DEPOSITS [J].
KENT, DV ;
NINKOVICH, D ;
PESCATORE, T ;
SPARKS, SRJ .
NATURE, 1981, 290 (5805) :393-396
[10]   THE LEAST-SQUARES LINE AND PLANE AND THE ANALYSIS OF PALEOMAGNETIC DATA [J].
KIRSCHVINK, JL .
GEOPHYSICAL JOURNAL OF THE ROYAL ASTRONOMICAL SOCIETY, 1980, 62 (03) :699-718