摘要
Changes in the morphology and mineralogy of speleothems (flowstones) clearly respond to climate-related phenomena, such as drip rate variability and temperature-modulated cave ventilation. Detailed petrographic observations have been coupled with <em><em style="font-family:Verdana;white-space:normal;"><em style="font-family:Verdana;white-space:normal;">δ</em></em></em><sup style="font-family:Verdana;white-space:normal;">18</sup><span style="font-family:Verdana;white-space:normal;">O</span><sup></sup> and <span style="font-size:12px;font-family:Verdana;"><em>δ</em></span><span style="font-size:12px;font-family:Verdana;"><sup>13</sup>C values. Fabrics may show changes related to variations in supersaturation, drip rate or input of detrital particles or organic compounds. Fabrics formed under relatively constant and regular drips (columnar compact, open and elongated) show similar <em>δ</em><sup>18</sup>O and <em>δ</em><sup>13</sup>C values, which are more negative than those of micrite and microsparite. The combination of internal microstratigraphy studies and isotopic data (<em>δ</em><sup>18</sup>O and <em>δ</em><sup>13</sup>C) from two flowstones collected from two caves in the north of Almeria province (SE Spain), suggest a spectrum of environmental conditions ranging from wetter to drier periods. Both records constitute a very useful tool for screening and interpreting high-resolution paleoclimate reconstructions.</span>
Changes in the morphology and mineralogy of speleothems (flowstones) clearly respond to climate-related phenomena, such as drip rate variability and temperature-modulated cave ventilation. Detailed petrographic observations have been coupled with <em><em style="font-family:Verdana;white-space:normal;"><em style="font-family:Verdana;white-space:normal;">δ</em></em></em><sup style="font-family:Verdana;white-space:normal;">18</sup><span style="font-family:Verdana;white-space:normal;">O</span><sup></sup> and <span style="font-size:12px;font-family:Verdana;"><em>δ</em></span><span style="font-size:12px;font-family:Verdana;"><sup>13</sup>C values. Fabrics may show changes related to variations in supersaturation, drip rate or input of detrital particles or organic compounds. Fabrics formed under relatively constant and regular drips (columnar compact, open and elongated) show similar <em>δ</em><sup>18</sup>O and <em>δ</em><sup>13</sup>C values, which are more negative than those of micrite and microsparite. The combination of internal microstratigraphy studies and isotopic data (<em>δ</em><sup>18</sup>O and <em>δ</em><sup>13</sup>C) from two flowstones collected from two caves in the north of Almeria province (SE Spain), suggest a spectrum of environmental conditions ranging from wetter to drier periods. Both records constitute a very useful tool for screening and interpreting high-resolution paleoclimate reconstructions.</span>
作者
Concepción Jiménez de Cisneros
Antonio González-Ramón
Cristina Sequero
Bartolomé Andreo
Ian J. Fairchild
Concepción Jiménez de Cisneros;Antonio González-Ramón;Cristina Sequero;Bartolomé Andreo;Ian J. Fairchild(Instituto Andaluz de Ciencias de la Tierra, CSIC-UGR, Granada, Spain;Instituto Geológico y Minero de España, IGME, Granada, Spain;Departamento de Ciencias de la Tierra, Universidad de Zaragoza, Zaragoza, Spain;Departamento de Geología, Centro de Hidrogeología, Universidad de Málaga, Campus de Teatinos, Málaga, Spain;School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham, UK)
