scholarly journals ¿PUEDE HABER 5 FASES DE DEFORMACIÓN HERCÍNICA EN LA ZONA DE VALDEMORILLO (MADRID)?

2020 ◽  
Author(s):  
Elena Real Fernández

This work aims to understand the processes that have taken part in the deformation, both on a small and large scale, of metamorphic materials in Valdemorillo area, located in the west of the Community of Madrid and within the Spanish Central System. The objective is to understand the kinematic evolution and the specific mechanical behaviour of igneous-metamorphic materials from the area, deformed by certain efforts developed throughout the Hercynian Orogeny. Therefore, a structural analysis has been carried out throughout a geological mapping scaled 1: 25000 and the analysis of various petrographic studies by microscope. Thus, a total of 5 different deformations have been identified, which have allowed us to better understand the reconstruction of the processes generated in these materials and that we see today.

1994 ◽  
Vol 131 (1) ◽  
pp. 67-80 ◽  
Author(s):  
Ole Petter Wennberg ◽  
Arild Andresen ◽  
Sigurd Hansen ◽  
Steffen G. Bergh

AbstractThe geometry and kinematic evolution of a frontal ramp section associated with the Tertiary West Spitsbergen Orogenic Belt has been investigated in a small area (Lappdalen) north of Isfjorden. The previously recognized thrust front corresponds to a complex step or ramp in the position of the sole-thrust in the area. The sole-thrust is localized to the evaporites of the Permian Gipshuken Formation to the west of the footwall ramp, whereas to the east it continues as a bedding-parallel thrust in Triassic shales (Sassendalen Group). The area to the west of the footwall ramp is characterized by large scale thrusts and folds involving the Permian Gipshuken and Kapp Starostin formations and the lower part of the Triassic Sassendalen Group. East of the footwall ramp both Permian and Triassic strata are sub-horizontal and apparently undeformed. Three major thrust sheets are recognized. Based on the geometric relationship between folds and faults in the area, both fault-bend and fault-propogation mechanisms of folding are inferred. Restoration of the Kapp Starostin Formation to its pre-deformational state indicates a minimum of 35% shortening. Structural observations within the Sassendalen Group in the study area and on Dickson Land suggest that some of this shortening is transmitted eastwards along one or more bedding parallel thrusts in the Sassendalen Group.


2016 ◽  
pp. 21-32 ◽  
Author(s):  
Helbert Garcia ◽  
Giovanny Jimenez

We report geological mapping, recollection of kinematic data, fracture data and transverse sections along the Zipaquira Anticline (ZA) used to recognize the deformation mechanisms involved in the kinematic evolution of the ZA. The Zipaquira Anticline (ZA) is an assimetrical fold with variation in the strike of fold axis and affected by some transverse faults (Transverse Zones) along its extension. The main fracture set in the ZA was formed in a pre-folding stage (J1), controlling the formation and propagation of sin-folding fractures (J2). Another fracture set (J3) was only recognized near the Zipaquira Lineament where several factors converge to deform considerably the rocks (e.g. Salt diapirs). We calculate the stress tensor from kinematic data, resulting in fractures formed in an extensional environment induced by diapir intrusion in the fold core. According to the transverse sections and previous considerations, thickness variation in Upper Cretaceous-Paleocene formations may indicate the onset of the pre-Andean Orogeny and the uplift of separated blocks, controlled by the transverse zones.


2021 ◽  
pp. 001139212110246
Author(s):  
Walid Habbas ◽  
Yael Berda

This article delves into the everyday dynamics of colonial rule to outline a novel way of understanding colonized–colonizer interactions. It conceives colonial management as a social field in which both the colonized and colonizers negotiate and exchange resources, despite their decidedly unequal positions within a racial hierarchy. Drawing their example from the West Bank, the authors argue that a Palestinian economic elite has proactively participated in the co-production of the colonial management of spatial mobility, a central component of Israeli colonial rule. The study employs interviews and document analysis to investigate how the nexus between Palestine’s commercial-logistical needs and Israel’s security complex induced large-scale Palestinian producers to exert agency and reorder commercial mobility. The authors describe and explain the evolution of a ‘Door-to-Door’ logistical arrangement, in which large-scale Palestinian traders participate in extending Israeli’s system of spatial control in exchange for facilitating logistical mobility. This horizontal social encounter that entails pay-offs is conditioned, but not fully determined, by vertical relations of domination and subordination.


2020 ◽  
Vol 23 (3) ◽  
pp. 189-205 ◽  
Author(s):  
Françoise Naudillon

The documentary film C’est ma terre by Fabrice Bouckat screened during the 2019 edition of Terrafestival is one of the first large-scale films produced locally on the crisis of the chlordecone molecule. This article will examine from a decolonial perspective, how its director, a Martinican with Gabonese origins who lives and works in Guadeloupe, develops a synthetic and universal vision of environmental crises, and thus demonstrates that destruction of ecosystems crosses time and space, cultures and lands, languages and peoples by bringing ecological crisis in the West Indies closer to the one experienced by the Vietnamese victims of Agent Orange.


Radiocarbon ◽  
1986 ◽  
Vol 28 (2A) ◽  
pp. 391-396 ◽  
Author(s):  
Reiner Schlitzer

The renewal of east Atlantic deep water and its large-scale circulation and mixing have been studied in observed distributions of temperature, silicate, ΣCO2, and 14C. 14C variations in northeast Atlantic deep water below 3500m depth are small. Δ14C values range from − 100‰ to −125‰. 14C bottom water concentrations decrease from Δ14C =−117‰ in the Sierra Leone Basin to Δ14C = − 123‰ in the Iberian Basin and are consistent with a mean northward bottom water flow. The characteristic of the water that flows from the west Atlantic through the Romanche Trench into the east Atlantic was determined by inspection of θ/Δ14C and θ/SiO2 diagrams. A mean potential temperature of θ = 1.50 ± .05°C was found for the inflowing water. A multi-box model including circulation, mixing, and chemical source terms in the deep water has been formulated. Linear programing and least-squares techniques have been used to obtain the transport and source parameters of the model from the observed tracer fields. Model calculations reveal an inflow through the Romanche Trench from the west Atlantic, which predominates over any other inflow, of (5 ± 2) Sv (potential temperature 1.50°C), a convective turnover of (150 ± 50) years and a vertical apparent diffusivity of (4 ± 1) cm2/s. Chemical source terms are in the expected ranges.


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