Provenance and tectonic settings of sands from Puerto Penasco, Desemboque and Bahia Kino beaches, Gulf of California, Sonora, Mexico

Textural, heavy minerals and geochemical (major, trace and rare earth elements) studies were undertaken on the sands from Puerto Penasco, Desemboque and Bahia Kino beaches to determine the provenance and tectonic settings. Puerto Penasco and Bahia Kino sands are coarse grained to fine grained, while Desemboque sands are fine grained. Geochemically, these sands are classified as arkose. The sands are depleted in most of the trace elements relative to upper continental crust (UCC), except for few trace elements (Sr, Rb and Ba), which are slightly enriched. High FREE content are observed in the Desemboque sands (94.43 +/- 6.9) than in the Puerto Penasco and Bahia Kino sands (51.58 +/- 17.06; 72.38 +/- 9.27; respectively). The chemical index of alteration (CIA) values of Puerto Penasco, Desemboque and Bahia Kino sands (PP: 42 to 50; DE: 48 to 50; BK: 44 to 50: respectively) indicate the low intensity of chemical weathering in the source rocks. The tectonic discriminant-function-based multidimensional diagram shows arc and rift settings for Puerto Penasco sands whereas rift setting for both Desemboque and Bahia Kino sands. The heavy mineral assemblage, immobile trace elements, REE patterns, elemental ratios such Eu/Eu*, (La/Lu)cn, La/Sc, Th/Sc, La/Co, Th/Co, and Cr/Th, various bivariate and ternary plots indicate the contribution of sediments from felsic composition. This interpretation is supported by the comparison of REE patterns of the Puerto Penasco, Desemboque and Bahia Kino sands with the potential source rocks exposed nearby the study areas. (C) 2016 Elsevier Ltd. All rights reserved.