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Correlación de cambios en la gravedad, la elevación y la tensión en el sur de California
Science (New York, N.Y.)
|March 11, 1983
Resumen
El sur de California experimentó una deformación significativa de la corteza entre 1977 y 1982. Los datos de gravedad, elevación y deformación revelaron cambios correlacionados, lo que indica verdaderos cambios geológicos.
Área de la Ciencia:
- La geofísica es la geofísica.
- La geodesia es una técnica de geodesia.
- La tectónica es la tectónica.
Sus antecedentes:
- El sur de California es una región sísmicamente activa propensa a la deformación de la corteza.
- Comprender el movimiento de la corteza terrestre es crucial para la evaluación del peligro sísmico.
Objetivo del estudio:
- Para investigar cambios correlacionados en la gravedad, la elevación y la tensión en el sur de California.
- Para evaluar la validez de las mediciones de deformación de la corteza desde 1977-1982.
Principales métodos:
- Encuestas de gravedad precisas realizadas semestralmente.
- Repetidas encuestas de elevación a lo largo de largas líneas de base.
- Encuestas de alcance láser para medir la tensión superficial.
Principales resultados:
- La gravedad observada cambia hasta 25 microgals en 6 meses.
- Los cambios de elevación anuales alcanzaron los 100 milímetros sobre las líneas de base de 40-100 km.
- Cambios de cepa de área de 1-2 partes por millón detectados en todo el sur de California.
Conclusiones:
- Las mediciones correlacionadas de múltiples técnicas geodésicas sugieren una verdadera deformación de la corteza.
- Los hallazgos proporcionan evidencia de una actividad geológica significativa en el sur de California durante el período de estudio.
- A pesar de las preocupaciones de precisión, el acuerdo entre los sistemas apoya la realidad de los cambios observados.
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