GSA 2020 Connects Online

Paper No. 62-12
Presentation Time: 11:50 AM

VOLCANO-SEDIMENTARY AND LIMESTONES: JURASSIC ROCKS IN CHONGOYAPE DISCTIRICT, PERÚ


MARTINEZ-SACRISTAN, Hernando, Research, HMS Latin American Products & Services, 2918 Letourneau Dr, Longview, TX 75602 and LÓPEZ MESONES, Eleazar Mario, Universidad Nacional Pedro Ruiz Gallo de Lambayeque, Av. Pedro Ruiz 1483, Chiclayo, 14002, Peru

Following the comparison and contrast research that the author has been developing between Jurassic Triassic rocks present in the East Bank of North America and the West part of the old margin of the South American Continent, started since 2012, a region of Peru is presented here, Remember that the hypothesis is to try to find similarities between rocks in the different sedimentary basins of the mentioned regions on the two continents.

The methodology has been affected by Covid 19 pandemic restrictions; Photographic comparisons are made of the information base collected by the co-author Mario López Mesones, his descriptions, geological maps of public agencies and the author's visual experience of these outcrops.

Two Stratigraphic Formations are presented, La Leche- The Milk, (Early Jurassic) and Tinajones Formation, (Jurassic). La Leche Formation, composed of limestone with coarse to massive stratification; layers with almost horizontal geological structural disposition, flat morphology at the top and obviously, presence of vertical scarps in their geomorphology and topography in the outcrop. Large limestone blocks on top of the hill and presence of marble blocks (by tectonics), as remnants of erosion. In these rocks, the co-author has found Turritelas and brachiopods. Adjacent to Cerro La Cal is a paleo forest with Otozamites, covered by volcanic eruptions. Tinajones Formation, Jurassic, composed of volcanic-sedimentary rocks Andesite Tobas, Adamelite Toba reddish to violets interspersed with intermediate to thin layers of reddish siltstones and the traditional andesitic dikes with intermediate slope / dip to high by tectonic effects.

La Leche Formation was deposited DISCORDANTE on the volcano-sedimentary rocks of the Tinajones Formation, Jurassic. Both Formations present similar appearance to the Saldaña, Department of Tolima, among others in Colombia. Although in the National Geological Chart of Peru, the Cerro La Cal area appears in the Upper Triassic and Jurassic although there is a new reinterpretation and this geomorphological structure would be at the beginning of the Jurassic. This would be the goal of a future more detailed study

El Cerro La Cal located northeast of the city of Chiclayo, in the Chongoyape District, near the town of El Palmo in Cuculí. It is located 45 minutes from Chiclayo, by car.