Current Trends in Natural Sciences Vol. 7, Issue 13, pp. 170-175, 2018 Current Trends in Natural Sciences (on-line) Current Trends in Natural Sciences (CD-Rom) ISSN: 2284-953X ISSN: 2284-9521 ISSN-L: 2284-9521 ISSN-L: 2284-9521 http://www.natsci.upit.ro *Corresponding author, E-mail address: codrutza_dobrescu@yahoo.com 170 RESEARCH ON THE POROSITY OF THE MESO-METAMORPHIC CRYSTALLINE SCHIST IN SOME SCREE IN LEAOTA MOUNTAINS Magdalin Leonard Dorobăţ 1 , Anca Gabriela Turtureanu 2 , Codruţa Mihaela Dobrescu 1* 1 University of Piteşti, Faculty of Science, Physical Education and Informatics, Department of Natural Sciences, Târgu din Vale Street, No. 1, 110040, Pitesti, Romania 2 University “Danubius” of Galaţi, Faculty of Economic Sciences, B-dl Galaţi no. 3, 800654, Galaţi, Romania Abstract Scree, as the main result of the gelivation (gelifraction) processes, represents a very interesting habitat type through the ecologic particularities it has. The formation and the spreading of scree is strongly related to the type of rock that generated it. Different types of rock lead to a different behavior against gelifraction and also against meteorization and bio-meteorization (chemical and biochemical alteration). Some of the mechanical features of rocks are defining regarding the higher or lower susceptibility of generating scree. The present paper is the result of the research on the porosity of meso-metamorphical crystalline schist extracted from different types of scree located on the north-western side of Leaota Mountains. It represents the continuation of some research of similar researches on limestone scree in the previously mentioned geographical area, leading to the conclusion that one can make a comparison between the two categories of rocks (limestone and schist) regarding their porosity and the way through which this geo-mechanical feature makes its mark on their behavior against the action of external features. The present paper is part of a complex assembly of researches on the way through which the geological component of the mesovoid shallow substratum (MSS) (in our case, the scree) leads, in a direct or indirect manner, to defining ecologic particularities of this habitat type and thus it influences the distribution of some zoocoenosis components. Keywords: chemical alteration, gelifraction, MSS, porosity, schist, scree. 1. INTRODUCTION This paper represents the result of the studies on the total porosity and of the open porosity in the case of the clasts which compose the meso-metamorphical crystalline schist scree which spreads on the north-western slope of the Leaota Mountains. These researches are a continuation of the ones on the limestone scree in the same area. This way, one can make a comparison between the two scree types, the scree and the limestone ones. Basically, the different behavior of limestone reported to the schist against the chemical, biochemical alteration processes and against gelifraction/gelivation (Matthews, 2013) or frost-shattering (Gutiérrez, 2013); congelifraction (Kurtz, 2004; Gutiérrez, 2013), is determined by the open porosity, namely by the pores that intercommunicate and through which water circulates. Open porosity has a defining role in the capacity of the rock of absorbing water, also determining its resistance against the frost-defrost cycles and permeability, the ability of the rock of chemically and biochemically reacting to water and the micro-organic load in the alteration processes. Moreover, the capacity of the rock of absorbing water leads to the existence of a high relative humidity from depths of just several tens of centimeters, humidity which persists all over the year. This contributes to the emergence of an interesting living environment in this scree,