Tectonic framework of Tiburon Basin, Gulf of California, from seismic reflection evidence

Transtensional rifting in the proto-Gulf of California near Bahia Kino, Sonora, Mexico

“…Its location, strike, and dip are neither observed nor constrained. Both the Infi ernillo on November 20, 2013 gsabulletin.gsapubs.org Downloaded from and Sacrifi cio faults continue northwest of the study area and likely trend into other NWstriking structures on northeastern Isla Tiburón (Bennett et al, 2012) and beneath the Gulf of California (Mar-Hernández et al, 2012), and also to the southeast, parallel to the shoreline, and concealed by the Rio Sonora delta plain (Fig. 1).…”

“…The dextral Bahía Kino fault consists of three NW-striking branches that truncate all pre-Quaternary map units in the central and southern parts of the study area. These branches are the best exposed strike-slip faults in the study area, and their orientations (310°-320°) are subparallel to offshore dextral structures within both the active (Fenby and Gastil, 1991) and abandoned (Aragón-Arreola and Martín- Barajas, 2007;Mar-Hernández et al, 2012) rift basins (e.g., De Mar fault; Fig. 1).…”

Thick deltaic sedimentation and detachment faulting delay the onset of continental rupture in the Northern Gulf of California: Analysis of seismic reflection profiles

“…Additional reprocessing of the same seismic lines was completed at Centro Nacional de Procesado Sismólogico (PEMEX) using ProMax© (workflow 1). Subsequent processing of seismic lines in specific regions was completed during Master thesis projects at CICESE (workflow 2) using ProMax software [Aguilar-Campos, 2007;Hernández-Pérez, 2008;Mar-Hernández, 2009;Soho, 2012]. Seismic lines 5028, 5040, 5042, and 5044 were scanned and vectorized from film copies held at PEMEX archives.…”

“…This region may illustrate the effects of a thick sedimentary section during the thinning and rupturing of the crust and lithospheric mantle because it records the transition from continental to oceanic rifting in two diachronous, subparallel rhombochasm basin systems located along the same transport parallel transect: (1) the active Delfin, Consag, Wagner, Cerro Prieto, and Salton basins in the west and (2) the inactive Tiburón‐Tepoca‐Altar basin system in the east [ Aragon‐Arreola and Martín‐Barajas , ] (Figure ). Both basin systems contain >6–7 km of sediments derived primarily from the Colorado River since latest Miocene time; [ Dorsey et al ., ; González‐Escobar et al ., ; Helenes et al ., ; Mar‐Hernández et al ., ], but the two sets of basins have distinctly different histories of rifting and continental rupture.…”

“…We find that the width of new crust, which forms in the wake of continental rupture, is much smaller than the larger width of new oceanic crust seen in the Guaymas and Alarcon basins to the south. The general basin geometry and master faults in the northern Gulf of California are known from interpretation of portions of the PEMEX seismic data [Aragon-Arreola and Martín-Barajas, 2007;González-Escobar et al, 2009;Mar-Hernández, 2009;Pacheco et al, 2006]. Here we use 90% of the available seismic array to document the fault geometry and extent of thinned continental crust that floors a pair of major rift basins located along the same transport-parallel transect in the northern gulf: Tiburón and Delfin basins (Figure 1).…”