Geomorfología litoral y significación de las variacones del nivel del mar

Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu

A Derivation of Three-Dimensional Inertial Transformations

The derivation of the transformations between inertial frames made by Mansouri and Sexl is generalised to three dimensions for an arbitrary direction of the velocity. Assuming lenght contraction and time dilation to have their relativistic values, a set of transformations kinematically equivalent to special relativity is obtained. The ``clock hypothesis'' allows the derivation to be extended to accelerated systems. A theory of inertial transformations maintaining an absolute simultaneity is shown to be the only one logically consistent with accelerated movements. Algebraic properties of these transformations are discussed. Keywords: special relativity, synchronization, one-way velocity of light, ether, clock hypothesis.Comment: 16 pages (A5), Latex, one figure, to be published in Found. Phys. Lett. (1997

Instrumentation for Millimeter-wave Magnetoelectrodynamic Investigations of Low-Dimensional Conductors and Superconductors

We describe instrumentation for conducting high sensitivity millimeter-wave cavity perturbation measurements over a broad frequency range (40-200 GHz) and in the presence of strong magnetic fields (up to 33 tesla). A Millimeter-wave Vector Network Analyzer (MVNA) acts as a continuously tunable microwave source and phase sensitive detector (8-350 GHz), enabling simultaneous measurements of the complex cavity parameters (resonance frequency and Q-value) at a rapid repetition rate (approx. 10 kHz). We discuss the principal of operation of the MVNA and the construction of a probe for coupling the MVNA to various cylindrical resonator configurations which can easily be inserted into a high field magnet cryostat. We also present several experimental results which demonstrate the potential of the instrument for studies of low-dimensional conducting systems.Comment: 20 pages including fig

Análisis de secuencias de islas barrera pleistocenas en relación con variaciones del nivel del mar, laguna de La Mata (Alicante)

En la laguna de La Mata (Alicante) se estudia un complejo de cordones litorales pleistocenos que forman el cierre de la actual laguna. Se analizan las secuencias resultantes y los posibles indicadores de variaciones del nivel del mar. Asimismo se interpretan estos depósitos en base a una curva aparente de tendencias del nivel del mar, obtenida con la suma de las componentes eustáticas cíclicas y la componente relativa debida al factor tectónico aplicado. [ABSTRACT] A complex of Pleistocene coastal barriers is studied in La Mata lagoon (Alicante). The resuting sequences are analyzed in order to establish indicators 0f sea level changes. These deposits can be correlated with an apparent curve of sea level tendencies obtained with the sum of the cyclic eustatic component and the relative component due to the tectonic factor applied

Holocene aeolian phases and human settlements along the Atlantic coast of southern Spain

A combined geomorphological, radiocarbon dating, archaeological and historical approach permits a refining of the age of the coastal dune systems related to estuaries in the Gulf of Cadiz. Three dune systems are distinguished in this paper. The oldest one, DI, which accumulated under prevailing WSW winds during the first millennium BC, overlays both the occupational horizons of Late Neolithic-Early Copper Age (fourth millennium BC) and the 'lithic workshop levels' (fourth to second millennia BC). The middle dune system, D2, containing both Roman and medieval remains, accumulated between the thirteenth or fourteenth centuries and the seventeenth century AD. The youngest D3 system is associated with the time of building of watchtowers in the seventeenth century AD but extends to the present; it is related to SW prevailing winds. We explain the absence of aeolian deposits prior to ~2700 cal. BP as the result of trapping of a large part of the sediment supply in the estuaries, which starved the neighbouring beaches and aeolian settings. Aeolian accumulation reached significant values when sedimentation in the coastal zone changed from being mainly aggradational in the estuaries (~6500~2700 cal. BP) to mainly progradational in spit barriers and related dunes (post ~2700 cal. BP). The present analysis of aeolian systems suggests a non-direct correlation, at least in some cases, between coastal progradation of spit barriers and aridity