Descripción de facies de la formación suretkaEn los alrededores de Siquirres y su relación con ambientes de depositación

Revista Geologica de America Central

Salazar, Jorge¹  Vargas, Asdrúbal G.¹  Barrantes, Manuel¹ 

[1] Instituto Costarricense de Electricidad, CR

关键词: facies;    conglomerate;    Suretka Formation;    Limón Basin;    sedimentation environment.;   

DOI  :  10.15517/rgac.v0i57.30149

学科分类：地质学

来源: Universidad de Costa Rica * Editorial

【 摘 要 】

In this work a description of sedimentary facies identified for the Suretka Formation near the town of Siquirres, Limón, is presented. The description was carried out with the inspections of underground excavations, outcrops in creeks, shafts, and boreholes during the construction stage of the Reventazón Hydroelectric power plant. Three sedimentary facies were identified: conglomerate facies, sandstone lenses with fine to very fine conglomerate and tuff lenses facies. The conglomerate facies is characterized by igneous blocks sumerged in a loam sandy matrix. These facies have metric to decametric bedding with bad gradation. On the other side facies of sandstone lenses and fine conglomerates are described as strata of the centimeter order with presence of both parallel and cross laminations in sandstone lenses and reverse and normal gradations in fine conglomerate lenses. The facies analysis allows the identification of an environment of subareal deposition associated with alluvial fans. For the facies of conglomerates, a proximal alluvial fan environment is established and for the facies of lenses of sandstones and intercalations of fine to very fine conglomerates a environment of medium alluvial fan with meandering sedimentary processes like longitudinal or point bars.

【 授权许可】

Unknown