[en] Caves developed in granite terrains are landscapes little know so far. But despite the few and scattered references in the scientific literature to such type of caves, the Atlas on Pseudokarst written by CHABERT & COUBORN (1997) includes a hundred of large cavitites located in plutonic rocks, a number which is increasing every day. This Thesis is in general focused on the caves developed in granites (plutonic rocks) and especially on the large granite cave systems of Iberia Peninsula. In a first phase they will be mapped erosional forms, structural forms and depositional (mainly speleothems and biospeleothems) forms, to develop specific geomorphological maps (plan and elevation views, crossover profiles, 3D models), on which will be intented to define a chronology for these cavities and also the active and fossil dynamics which are present in this type of underground environment. These caves can be of three types. The first type are fissure caves, which are developed taking advantage in those fault or fracture planes where weathering proccesses was well developed and where the alterites were removed after by erosion. The second type, and here belongs to the majority of the samples that will be studied in this Thesis, have been defined taking advantage of existing voids in slope deposits formed by gravitational collapse of blocks. In most cases the size of the gaps among blocks depend entirely on the dimensions of the blocks. Some times when the accumulations of blocks occur at the valey bottoms, the runoff waters are channelized through these gaps, although the water scarcely produces changes in space than pot holes or erosion channels. In other cases boulder caves have been developed by opening convex forms (tor, castle kopje, inselbergs, etc), (that is) in which previous rock structure has been opened by rock(y) creep giving place to the cavity due to the separation of blocks. The deposits inside these cavities preserve sedimentary records of different entity from which we can get information on the evolution of the underground environment since the cave is formed. The third type of caves, of great singularity though more modest dimensions, are tafoni caves. Here the cavity is limited to the scope of the block affected by the process. From the three types of granite caves, this Thesis is specifically focused in the second one. The first part of this Thesis studies the genesis of these caves, and so defining as far as possible, the involved mechanisms that produce block and boulder movements and also the chronology of these movements, both aspects often intractable especially by the lack of an appropriate criteria. The second part of the Thesis studies the microclimatic characteristics that defining the underground environment. Our objective is to build a mathematical model (black-box or gray-box model) which copy the underground microclimatic dynamic inside these type of caves. Many works on karst caves assume that caves are causal dynamic systems, continuous, invariant on time and lineal. However the first data analyzed shows that these type of caves should be processed using no-lineal dynamic system identification strategies. So mathematical models will be developed using artificial neural networks, mainly those specialized on processing time series. These networks are characterized by their learning, generalization and abstraction capacities, and so they are capable to develop and extend continuous models from broken datasets (series). Multiparametric mono or multiobjective optimization will be solved by heuristic approaches. As previous phase to system identification, it must be determined the correlation among physic variables that interact in the system and that in our problem all they are long not-stationary time series. We will use wavelet transforms due they are an specialized tool to study not-stationary process, multiscale, and developed both in finite spatial and time domains. Another part ot this Thesis is focused on the assessment and risk analysis of these systems: On one hand many of these cavities are draining important water courses and so there is a risk of avenues especially dangerous for visitors. Also by the type of lithology and when there isn't drainage through the cave, a potential risk arising from high levels of radon are added, which can become these cavities in traps or natural deposits of this type of gas and their children radioactive subproducts (cesium). On the other hand these caves are accumulations of blocks of large thickness which requires to analyze stability and their potential risk of reactivation.

[gl] As cavidades en rochas plutónicas son un medio pouco coñecido polo de agora. Mais a pesar das poucas e dispersas referencias a iste tipo de covas na literatura científica, o Atlas sobre pseudocasrt de CHABERT e COUBORN (1997), inclúe un centenar de grandes covas emprazadas en rochas plutónicas, un número que se incrementa cada día. Esta Tese céntrase de forma xeral nas covas desenvoltas en granitos (rochas plutónicas) e especificamente nos grandes sistemas de covas en granitos da Península Ibérica. Nunha primeira fase elaborarase unha cartografía xeomorfolóxica específica (planta, alzados, seccións, modelo 3D), cartografiando formas de erosión, formas estruturais e formas de acumulación (espeleotemas e bioespeleotemas), en base á que se tratará de definir unha cronoloxía pra istas cavidades e máis as dinámicas activa e fósil que se atopan neste tipo de medios baixoterreños. Estas covas poden ser de tres tipos. O primeiro tipo son as covas de fisura, desenvoltas aproveitando os planos de falla o de rotura que teñen canalizado os procesos de meteorización e logo teñen sido valeiradas das súas alteritas pola erosión. O segundo tipo, e é ó que pertencen a maior parte das covas que se estudan nesta Tese, definíronse aproveitando os ocos existentes nos depósitos de vertente formados polo colapso gravitatorio de bloques. As veces cando a acumulación dos bloques acontece nos fondos dos vales, a escorrentía superficial canalízase a través deste ocos inda que a auga apenas desenvolve modificacións no espazo soterraño mais aló de marmitas e canles de erosión. Noutros casos as covas de bloques desenvolvéronse pola apertura de formas convexas (tor, castle kopje, inselbergs, etc), nas que a estrututra previa da rocha abríuse por esvaramento, xenerándose o óco pola separación dos bloques. No interior destas cavidades os depósitos preservan rexistros sedimentarios de distinta entidade dos que se pode obter información sobre a evolución do medio baixoterreño dende que se desenvolveu a cavidade. O terceiro tipo de covas, de grande singularidade inda que de dimensións máis modestas, son as cacholas. Neste tipo, a cavidade limítase ao ámbito do bloque afecto polo proceso. Dos tres tipos de covas, ista Tese adícase específicamente ao segundo tipo. A primeira parte da Tese refírese ao estudo da xénese destas covas definindo no posible os mecanismos implicados no movemento dos bloques e a cronoloxía do movemento, ambos aspectos moitas veces irresolubeis especialmente pola ausencia de criterios axeitados. A segunda parte do proxecto de Tese refírese á definición das características microclimáticas que definen o entorno baixoterreño. Preténdese conseguir un modelo matemático (gray-box ou black-box model) que represente a dinámica do microclima neste tipo de covas. Moitos traballos sobre o carst asumen que as covas son sistemas dinámicos causais, continuos, invariantes no tempo e liñais. Nembargantes os primeiros ensaios realizados amosan que istas covas deberían tratarse con técnicas de identificación de sistemas dinámicos non liñais. Así os modelos construiranse mediante redes neuronais artificiais con topoloxías especializadas en series temporais. Istas redes presentan como características fundamentais a súa capacidade de apredizaxe, xeneralización e abstracción, o que permite obter modelos continuos a partir de series de datos "rotas". A optimización multiparamétrica mono o multiobxetivo resolverase mediante métodos heurísticos. Como fase previa á identificación débese determinar a correlación entre as variables físicas que interveñen no sistema e que se presentan como series temporais longas non estacionarias. Farase uso de transformadas wavelet por canto téñense amosado como unha ferramenta de análisis especializada no estudo de procesos non estacionarios, multiescala e desenvoltos nun dominio finito espacial e temporal. Outra parte da Tese céntrase na evaluación e análise dos riscos destes sistemas: Por un lado moitas destas cavidades son a drenaxe de cursos de auga importantes e presentan un risco de avenidas especialmente perigoso para os visitantes. Tamén polo tipo de litoloxía e no caso de que non exista drenaxe a través delas, engádense os riscos derivados dos altos niveis potenciais de radón, o que pode convertir a istas cavidades en trampas ou depósitos deste tipo de gas e produtos radioactivos derivados (cesio). Por outra banda istas covas son acumulacións de bloques de gran potencia, o que conleva analizar cal é a súa estabilidade e cal o seu risco potencial de reactivación.