A gravity survey on Mizuho Plateau was carried out in austral summer of 2001-2002 by the 43rd Japanese Antarctic Research Expedition (JARE-43), as one of the geophysical measurements of deep seismic exploration. Gravi...A gravity survey on Mizuho Plateau was carried out in austral summer of 2001-2002 by the 43rd Japanese Antarctic Research Expedition (JARE-43), as one of the geophysical measurements of deep seismic exploration. Gravity measurements were conducted at 151 points in approximately 1 km interval along the 150 km profile. Considering the gravity effect from the ice-sheet, Free-air and Bouguer anomalies were calculated by using precise GPS locations. Furrowed and basin-like negative Free-air anomalies were observed in middle and northern parts of the profile. Bouguer anomalies were calculated by two bedrock elevation data obtained from seismic refraction and radio-echo sounding. High resolution model for bedrock elevation by radio-echo sounding was applied in determining the crustal thickness.展开更多
This study provides new insights into the nature of seasonal variations in coordinate time series of GPS sites located near active faults and methods of their modeling. Monthly averaged coordinate time series were ana...This study provides new insights into the nature of seasonal variations in coordinate time series of GPS sites located near active faults and methods of their modeling. Monthly averaged coordinate time series were analyzed for several pairs of collocated GPS sites situated near the active fault intersection area, in close proximity to the central part of the northern boundary of the Amurian plate and the vicinity of the San Andreas Fault zone. It is concluded that the observed seasonal variations are best described by a breather function which is one of the solutions of the well-known sine-Gordon equation. The obtained results suggest that, in this case, the source of seasonal variations may be caused by the appearance of solitary strain waves in the fault intersection system, which may be qualitatively treated as standing waves of compression-extension of the geological medium. Based on statistical testing, the limits of applicability of the suggested model have been established.展开更多
文摘A gravity survey on Mizuho Plateau was carried out in austral summer of 2001-2002 by the 43rd Japanese Antarctic Research Expedition (JARE-43), as one of the geophysical measurements of deep seismic exploration. Gravity measurements were conducted at 151 points in approximately 1 km interval along the 150 km profile. Considering the gravity effect from the ice-sheet, Free-air and Bouguer anomalies were calculated by using precise GPS locations. Furrowed and basin-like negative Free-air anomalies were observed in middle and northern parts of the profile. Bouguer anomalies were calculated by two bedrock elevation data obtained from seismic refraction and radio-echo sounding. High resolution model for bedrock elevation by radio-echo sounding was applied in determining the crustal thickness.
文摘This study provides new insights into the nature of seasonal variations in coordinate time series of GPS sites located near active faults and methods of their modeling. Monthly averaged coordinate time series were analyzed for several pairs of collocated GPS sites situated near the active fault intersection area, in close proximity to the central part of the northern boundary of the Amurian plate and the vicinity of the San Andreas Fault zone. It is concluded that the observed seasonal variations are best described by a breather function which is one of the solutions of the well-known sine-Gordon equation. The obtained results suggest that, in this case, the source of seasonal variations may be caused by the appearance of solitary strain waves in the fault intersection system, which may be qualitatively treated as standing waves of compression-extension of the geological medium. Based on statistical testing, the limits of applicability of the suggested model have been established.
