$%675$&7Metabasites belonging to the Arquía Complex and outcropping along the Pijao-Génova strip (western edge of the Central Cordillera of the Colombian Andes) consist of chlorite schists, actinolite schists with and without garnet, amphibolites, garnet-amphibolites, eclogites and metabasalts. Some bodies of serpentinized peridotites are observed along with PHWDEDVLWHV %RWK URFN W\SHV DUH FRQ¿QHG WR WKH WHFWRQLF EORFN ERUGHUHG E\ WKH &DXFD$OPDJXHU DQG 6LOYLD3LMDR fault systems and their satellite faults. Metabasites were affected by a regional metamorphism, reaching their peak of metamorphism at the amphibolite facies. The Rare Earth Elements (REEs) (normalized to the C1 3DODEUDV FODYH Petrología; metabasitas; Complejo Arquía; Cordillera Central; Colombia.

This research article refers to the coastal region around Santa Marta (Colombia), showing a valuable geodiversity from a coastal geomorphology point of view, with great scientific importance for the study of coastal landscapes and attractive for the development of geotourism. The landscape value of the coastal regions of the Colombian Caribbean, in particular of the coastal region around Santa Marta, should be globally recognized to improve and protect its aesthetic and environmental value through geoeducation and geotourism activities that contribute to its geoconservation, motivating efficient management that outlines guidelines that promote the development of appropriate tourist infrastructure, centers of scientific interpretation, dissemination and educational materials, active exchange with geoparks, continuous improvement, and participation of local communities.

<p>High-pressure complexes along the Earth's surface provide evidence of the processes involved in both the crystallization of rocks in the subduction channel and its exhumation. Such processes are key to understand the dynamics and evolution of subduction zones and to try to reconstruct P-T trajectories for these complexes.</p><p>Previous studies on the Raspas complex (southern Ecuador) agree to state that it is composed of metamorphic rocks, mainly blueschists and eclogites, containing the mineral assemblage: glaucophane + garnet + epidote + omphacite + white mica + rutile ± quartz ± apatite ± pyrite ± calcite; which stabilized in metamorphic conditions of high pressure and low temperature. Additionally, the Raspas Complex has been genetically related to accretion and subduction processes of seamounts, which occurred in South America during the Late Jurassic - Early Cretaceous interval; and the exhumation of the complex was related to subduction channels. However, the evidence presented in the existing literature makes little emphasis on the reconstruction of thermobarometric models for the rocks of this complex.</p><p>By combining petrographic observations, whole-rock chemistry, and mineral chemistry in this work; it was possible to determine that pressure values of 10 ± 3 Kbar and temperature values of 630 ± 30 ° C, (obtained by simulations with THERMOCALC®) correspond to an event of retrograde metamorphism, suffered by the complex during its exhumation. This theory is complemented by the specific textures (that suggest this retrograde process) observed during petrographic analysis, such as amphibole replacing pyroxene, garnet chloritization, plagioclase crystallization and rutile replacement by titanite.</p><p>The results obtained, together with the thermobarometry data published for the Arquía complex in Colombia, allow us to establish a P-T trajectory, that may suggest a genetic relationship between these two complexes as a result of the tectonic processes associated with an active subduction margin that affected the NW margin of the South American plate at the end of the Jurassic.</p><p> </p>

El Itinerario Geológico de la franja costera comprendida entre el aeropuerto Internacional “Simón Bolívar” y la Bahía de Taganga, Provincia Geotectónica de Santa Marta, representa un laboratorio geológico natural de gran importancia para el entendimiento de la evolución geológica del margen noroccidental de Sur América. Este trabajo surge como resultado de las investigaciones realizadas por los autores durante varios años y contiene una síntesis actualizada y ampliamente ilustrada del estado de conocimiento de los lugares de interés geológico de esta región, siendo una contribución significativa para la literatura de la geología regional. Por primera vez se presenta un trabajo de tal naturaleza para el ámbito del Macizo Sierra Nevada de Santa Marta, en el que se destacan evidencias geológicas de fenómenos que han afectado nuestro planeta. La gran variedad temática de sus afloramientos (de interés estratigráfico, geomorfológico, mineralógico, petrológico, tectónico, etc.), junto a la calidad de exposición, hace que tengan un gran potencial científico y didáctico. Los lugares de interés geológico incluidos en el presente trabajo tienen, además de su valor científico y didáctico, un valor añadido gracias a su atractivo paisajístico. Su singularidad y belleza hace que algunos de estos lugares sean aprovechados como recurso geoturístico.

We report here for the first time the occurrence of chloritoid in Mg-Al-rich metapelitic rocks of the Silgará Formation at the Central Santander Massif, which was metamorphosed up to the amphibolite facies. These rocks contain an unusual mineral assemblage such as quartz + biotite + muscovite + garnet + staurolite ± kyanite ± chloritoid, with minor plagioclase and K-feldspar, and Fe-Ti oxides as the main accessory phases. Associated carbonate rocks containing the mineral assemblage tremolite + calcite. Chloritoid occurs as porphyroblastic tablets in graphite-bearing metapelitic schists highly tectonized that can be associated to the influence of the major tectonic structures in the study area. The occurrence of chloritoid as an index mineral in metapelitic rocks of the Silgará Formation is attributed to a thermal event (associated to the emplacement of small granitic masses) overimposed on the regional metamorphism.Key words: Chloritoid, Metapelitic rocks, Silgará Formation, Central Santander Massif, Colombian Andes.Ocurrencia de rocas metapelíticas con presencia de cloritoide y su significado en el metamorfismo de la Formación Silgará en la región central del Macizo de Santander ResumenEn el presente estudio se reporta por primera vez la aparición de cloritoide en metapelitas ricas en Mg-Al de la Formación Silgará en la región central del Macizo de Santander, las cuales fueron afectadas por un metamorfismo hasta en facies anfibolita. Estas rocas contienen una asociación mineral inusual, tal como cuarzo + biotita + moscovita + granate + estaurolita ± cianita ± cloritoide, con menor plagioclasa y feldespato potásico, y óxidos de Fe-Ti como las principales fases accesorias. Rocas carbonatadas asociadas contienen la asociación mineral tremolita + calcita. El cloritoide ocurre como porfidoblastos tabulares en esquistos metapelíticos con grafito fuertemente tectonizados que pueden asociarse a la influencia de las principales estructuras tectónicas en el área de estudio. La ocurrencia de cloritoide como un mineral índice en las rocas metapelíticas de la Formación Silgará se atribuye a un evento térmico (asociado al emplazamiento de pequeñas masas graníticas) sobreimpuesto al metamorfismo regional.Palabras clave: Cloritoide, Rocas metapelíticas, Formación Silgará, Región Central del Macizo de Santander, Andes Colombianos.