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....
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...
Anomaly timescales for the last 90 million years, derived from
marine magnetic profiles and published prior to mid-1979, are summarized,
illustrated for comparison, and critically reviewed. A revised timescale
is constructed using calibration points which fix the ages of anomalies
2.3', 5.5, 24, and 29. An equation is presented for...
Plankton and surface sediment samples from the Gulf of California
were analyzed to determine the present geographic distribution of silicoflagellate
species in this area. Variations in the composition of the
silicoflagellate assemblage are related to water mass distributions.
Seven species and three forms were identified in these samples. Octactis
pulchra...