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Liu, CS, Sandwell DT, Curray JR.  1982.  The Negative Gravity-Field Over the 85-Degrees-E Ridge. Journal of Geophysical Research. 87:7673-7686.   10.1029/JB087iB09p07673   AbstractWebsite

An isopach map made from seismic reflection and refraction data in the Bay of Bengal shows two prominent N-S trending features in the basement topography. One is the northernmost portion of the Ninetyeast Ridge which is totally buried by sediments north of 10°N. The other buried ridge trends roughly N-S for 1400 km at 85°E to the latitude of Sri Lanka and then curves toward the west. It has basement relief up to 6 km. Two free-air gravity anomaly profiles across the region show a strong gravity low (∼−60 mGal) over the 85°E Ridge, while the Ninetyeast Ridge shows a gravity high. To understand the negative free-air gravity anomaly over the 85°E Ridge, we model the lithosphere as a thin elastic plate and calculate its flexural and gravitational response to an uneven sediment load. A plausible formation history for a buried ridge consists of at least two major episodes. The first is the formation of the ridge on a lithosphere with a flexural rigidity of D1. At some later time the ridge is buried by an influx of sediments, the lithosphere is cooler, and the flexural rigidity has increased to D2. The character of the gravity field depends primarily upon the initial and final values of flexural rigidity. These D1 and D2 values are varied to obtain good agreement between the model and observed gravity anomalies. Best fitting models have a 180 times increase in flexural rigidity between ridge formation and sediment burial. An approximate relationship between flexural rigidity and crustal age shows that the 85°E Ridge was formed on relatively young lithosphere, 5–15 m.y. old and that it was buried when the lithosphere was 40–80 m.y. old.

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Sandwell, DT, Sichoix L, Agnew D, Bock Y, Minster JB.  2000.  Near real-time radar interferometry of the Mw 7.1 Hector Mine Earthquake. Geophysical Research Letters. 27:3101-3104.   10.1029/1999gl011209   AbstractWebsite

The Hector Mine Earthquake (Mw 7.1, 16 October 1999) ruptured 45 km of previously mapped and unmapped faults in the Mojave Desert. The ERS-2 satellite imaged the Mojave Desert on 15 September and again on 20 October, just 4 days after the earthquake. Using a newly-developed ground station we acquired both passes and were able to form an interferogram within 20 hours of the second overflight. Estimates of slip along the main rupture are 1-2 meters greater than slip derived from geological mapping. The gradient of the interferometric phase reveals an interesting pattern of triggered slip on adjacent faults as well as a 30 mm deep sink hole along Interstate 40.

Sandwell, DT, Müller DR, Smith WHF, Garcia E, Francis R.  2014.  New global marine gravity model from CryoSat-2 and Jason-1 reveals buried tectonic structure. Science. 346:65-67.   10.1126/science.1258213   AbstractWebsite

Gravity models are powerful tools for mapping tectonic structures, especially in the deep ocean basins where the topography remains unmapped by ships or is buried by thick sediment. We combined new radar altimeter measurements from satellites CryoSat-2 and Jason-1 with existing data to construct a global marine gravity model that is two times more accurate than previous models. We found an extinct spreading ridge in the Gulf of Mexico, a major propagating rift in the South Atlantic Ocean, abyssal hill fabric on slow-spreading ridges, and thousands of previously uncharted seamounts. These discoveries allow us to understand regional tectonic processes and highlight the importance of satellite-derived gravity models as one of the primary tools for the investigation of remote ocean basins.