Record Details
Crustal structure of the Baja Peninsula between latitudes 22 ̊N and 25 ̊N
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Crustal structure of the Baja Peninsula between latitudes 22 ̊N and 25 ̊N |
| Names |
Huehn, Bruce
(creator) Couch, Richard W. (advisor) |
| Date Issued | 1977-04-28 (iso8601) |
| Note | Graduation date: 1977 |
| Abstract | 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 the Baja peninsula, indicates normal faulting of the near surface sediment layers along the outer continental shelf. The reflection record also shows that sediment layers immediately above the acoustic basement dip toward the east at the base of the continental slope. A crustal and subcrustal cross section, oriented approximately parallel to the reflection profile and constrained by gravity, magnetic, bathymetric and seismic refraction data, indicates a maximum crustal thickness of approximately 21 km for Baja California, making it intermediate in thickness between normal continental and normal oceanic crusts. The section also indicates a low density zone in the mantle below the Gulf of California. Magnetic anomalies along the cross section require oceanic crust of the Pacific Plate to extend at least 50 km landward of the edge of the western continental shelf of Baja California. This suggests either a past period of oblique subduction of the Pacific Plate beneath Baja California or emplacement of Pacific Plate oceanic crust beneath the peninsula by descending spreading centers of the East Pacific Rise. |
| Genre | Thesis/Dissertation |
| Topic | Earth -- Crust |
| Identifier | http://hdl.handle.net/1957/29137 |
