Marine geophysical data from the continental margin of Baja
California and the Gulf of California, and geological and geophysical
data from the Baja California Peninsula and mainland Mexico, outline
the major geologic and tectonic features of the Baja California
Peninsula and the surrounding areas from 24.5° N. Lat. to 27.5°...
Geophysical data collected in 1975 and 1976 reveal major
crustal and tectonic elements of the continental margin of southern
Baja California. Gravity, magnetic, seismic reflection and bathymetric data show seaward extension of the islands enclosing Magdalena
and Almejas Bays. A seismic reflection profile, oriented
approximately normal to the trend of...
Data collected by personnel of the Geophysics Group at Oregon State
University and the Instituto Oceanografico of the Direccion General dé
Oceanografia are used to construct a free-air anomaly map for the central
part of the Pacific continental margin of Mexico, which shows the gravity
expression of major structural features...
A free-air gravity anomaly map of the area between 10°-17°N and
90°-101°W shows distinctive positive and negative anomalies which
parallel the Tehuatepec Ridge. The positive anomaly approximately
overlies the topographic expression of the ridge. On the wide continental
shelf southeast of the Gulf of Tehuantepec a positive gravity
anomaly with...
Geophysical surveys in the Gulf of California provided
the data to construct contour maps of bathymetry, free-air
anomalies and total field magnetic anomalies for the area
north of 27° N. Major faults such as the Ballenas-
Salsipuedes, Tiburón, Guaymas, and the South Cerro Prieto
are clearly observable on these maps....
Gravity, magnetic and seismic data indicate that the oceanic
crust is 9.7 km thick west of the Continental Borderland. The top
of the mantle is about 12 km deep under the Borderland, and deepens
to 27 km beneath the Peninsular Ranges of Baja California. The
mantle is about 20 km...
Gravity and magnetic data from cruises by the R/V Yaquina in 1973
and the R/V Wecoma in 1975 provide new data that make possible the construction of a map of the free-air gravity anomalies at sea and simple
Bouguer anomalies on lano in Panama, western Colombia, and the eastern
Panama...
Using gravity, magnetic, bathymetric and seismic
refraction data, I have constructed a geophysical cross-section
of the central part of the northern Gulf of California. The
section exhibits a crustal thickness of 18 km and features an
anomalous block of high density lower basement (3.15 g/cm³)
which probably resulted from rifting...
A free-air gravity anomaly map of the continental margin of
Peru between 12° and 18° S. Lat. shows a -110 to -220 mgl anomaly
associated with the Peru-Chile Trench, a -60 mgl anomaly over the
Pisco Basin on the continental shelf, and -120 mgl anomaly over the
Mollendo (or Arequipa)...
Gravity and seismic data obtained by the geophysical group at
Oregon State University on the R/V YAQUINA during 1969, 1971, and
1973 plus other available data over the area just west of Nicaragua
and Costa Rica indicate the tectonic complexity of the region. Gravity
measurements show negative free-air anomalies over...
Gravity measurements made during 1979 and 1980, combined with
existing gravity measurements, provide data for the interpretation
of upper crustal structures relevant to the assessment of the geothermal
potential of south-central Oregon.
West of Upper Klamath Lake, free-air gravity anomalies trend
north-south and average near 35 mgals. East of Upper...