Pedro J. Martínez-García

Miocene Shale Tectonics in the Northern Alboran Sea (Western Mediterranean)

The Alboran Basin is a back-arc basin in the Mediterranean developed during the Miocene by the extensional collapse of the thick continental orogen known as the Betic-Rif arc. Collision and basin formation occurred in the Neogene as a result of oblique convergence of the Eurasian and African plates. A major, curved depocenter (with sedimentary accumulations 10 km [6 mi]) is located to the west of this basin, containing a diapiric province with overpressured shales and mud volcanoes. This study presents a detailed reconstruction of the three-dimensional geometry of the diapirs and associated minibasins in the northern margin of this major depocenter (offshore Spain). Basin formation began in the early Miocene when rapid initial subsidence of the basin floor was accompanied by massive sedimentation and burial of fine-grained sediments. Gravity-driven tectonics and continuous basement subsidence during the Miocene led to downslope migration of mobile shales, whereas the basin margins were affected by synsedimentary extension, and associated shale-cored thrusts occurred in the basin depocenter. Extension occurred by means of low-angle normal faults coalescing with the basement surface, which represents a master detachment surface. Thin-skinned extension during the Miocene was accompanied by punctuated diapir ascent and the advance of shale sheets. Downslope shale advance was enhanced by counterregional high-angle normal faults isolating noncylindrical minibasins in the overburden. The Alboran Basin therefore is a useful area for analysis of the structural pattern associated with shale tectonic processes and a key basin for comparing the geometries and evolution of shale with structures formed in salt basins.

Molecular and phenotypic characterization of the S-locus and determination of flowering time in new 'Marcona' and 'Desmayo Largueta'-type almond (Prunus dulcis) selections

Abstract‘Marcona’ and ‘Desmayo Largueta’ are the most widely cultivated almonds in Spain, representing around 27% of the total production and 34% of the entire almond growing surface. The excellent quality of their kernels makes them highly appreciated and demanded worldwide. However, due to their self-incompatibility, they should be grown along with cross-compatible cultivars, whose lower kernel quality often reduces the economic benefits of the plantation. In addition, although they are cross-compatible, are not good candidates to share the orchard since ‘Desmayo Largueta’ usually flowers earlier than ‘Marcona’. Therefore, to optimize orchard yield, genotypes with overlapping flowering times, cross-compatible with these cultivars and of similar fruit and ripening characteristics are desirable. In order to find suitable pollinators of these cultivars, five ‘Marcona’ and four ‘Desmayo Largueta’-type selections from “Instituto Técnico Agronómico Provincial (ITAP) de Albacete” (Spain) were characterized for flowering time and for self and cross-incompatibility. The results obtained showed that the nine ITAP selections were self-incompatible, and that three and one were promising candidates as pollinators of ‘Marcona’ and ‘Desmayo Largueta’, respectively. The S-haplotypes of two ITAP selections were characterized by cloning and sequencing their pistil S (S-RNase) and pollen S (SFB) genes. The results also showed that Sf RNase does not have a mutated histidine in C2 region, and detected differences with other previously published sequences for S23RNase and SFB23 allele. Moreover, the sequence for almond SFB27 allele is reported here for the first time.