Articles

 

Boletín de la Sociedad Geológica Mexicana

Volumen 69, núm. 2, 2017, p. 479 ‒ 494

Influencia de la temperatura sobre la asimetría de pilancones en ambiente granítico. Aplicación de un modelo de regresión lineal

Manuel García-Rodríguez, Abel Sánchez-Jiménez, Antonio Murciano, Blanca Pérez-Uz, Mercedes Martín-Cereceda

 

Manuel García-Rodríguez
This email address is being protected from spambots. You need JavaScript enabled to view it.
Departamento de Ciencias Analíticas, Facultad de Ciencias Universidad Nacional de Educación a Distancia (UNED). Paseo Senda del Rey 9. 28040, Madrid (España).

Abel Sánchez-Jiménez
Antonio Murciano
Departamento de Matemática Aplicada (Biomatemática), Facultad de Ciencias Biológicas. Universidad Complutense de Madrid (UCM). 28040, Madrid (España).

 

Blanca Pérez-Uz
Mercedes Martín-Cereceda

Departamento de Microbiología III, Facultad de Ciencias Biológicas. Universidad Complutense de Madrid (UCM). 28040, Madrid (España).

 

Abstract

Weathering pits represent a kind of geological form present in almost all climatic environments. This manuscript explores the role of thermal cycles as important agents in the modelling and asymmetry of the walls of weathering pits in a temperate-cold Mediterranean climate. This study has been developed in the granite massif from La Pedriza in Manzanares which is a protected area, with a great environmental value, allocated in the National Park Sierra de Guadarrama (Madrid, Spain). The analysis of thermal variability was approached using periodic multiple regression that showed the influence of daily and annual cycles depending on the north and south orientation of the pit walls. A mathematical model of linear regression revealed the influence of the daily thermal variability on the alteration of the pit walls generating flat surfaces or a more or less pronounced concavity. This study also established relationships between the alteration degree of different areas of the pits with the lichen presence and with the relative hardness of the rock. The results support the hypothesis of a causal relationship between thermal variability and the shaping of the weathering pits depending on their north or south orientation.

Keywords: gnamma, mathematical modelling, weathering granite, La Pedriza de Manzanares.