The Guaymas Basin is one of several basins which have formed along the Pacific-North American plate boundary in the Gulf of California. Single-channel data crossing the basin reveals a sediment distribution that is difficult to reconcile with a model for sea-floor spreading in which all of the oceanic crust in the basin formed at a single, stable spreading center. Near the axis of the basin, the apparent sediment thickness on single-channel records is remarkably uniform; from the northern trough for more than 60 km to the southeast, the average thickness remains close to 0.5 s (or 500 m with a 2.0 km/sec constant sediment velocity). The multi-channel reflection profiles from the Guaymas Basin, collected on the basin site survey prior to Leg 64 of the Deep Sea Drilling Project (DSDP), show that the single-channel estimates of basin sediment thickness are too small. The sediment column visible on the multi-channel data is often more than three times as thick as that seen on the single channel records; ranging from less than 500 m in the central troughs to nearly 2 km at the boundary between oceanic and rifted continental crust between 60 km and 70 km from the center of the basin. The more realistic estimates of total sediment thickness from the multi-channel data suggests that a complex model for the formation of oceanic crust in the basin is unnecessary. The corrected basement depths calculated using the multi-channel sediment thickness show that, toward the center of the basin, the acoustic basement depths are similar to depths predicted by the subsidence of normal oceanic crust, though they are between 300 m and 600 m too shallow. The constant depth to acoustic basement of about 2300 m near the edges of the basin, and the anomalously shallow depths along the basin's axis, can be explained by processes which affect the crustal subsidence at the edges of the basin and the presence of a sill-sediment layer in the Guaymas Basin. The analysis of the geometry and superposition of seismic sequences shows that, near the middle of the basin, the details of the sediment column support a simple spreading model.