Search results for "Rock fragment"

Visible and near-infrared multispectral analysis of geochemically measured rock fragments at the Opportunity landing site in Meridiani Planum

2010

[1] We have used visible and near-infrared Panoramic Camera (Pancam) spectral data acquired by the Opportunity rover to analyze 15 rock fragments at the Meridiani Planum landing site. These spectral results were then compared to geochemistry measurements made by the in situ instruments Mossbauer (MB) and Alpha Particle X-ray Spectrometer (APXS) to determine the feasibility of mineralogic characterization from Pancam data. Our results suggest that dust and alteration rinds coat many rock fragments, which limits our ability to adequately measure the mineralogy of some rocks from Pancam spectra relative to the different field of view and penetration depths of MB and APXS. Viewing and lighting …

Analysis of soil surface component patterns affecting runoff generation. An example of methods applied to Mediterranean hillslopes in Alicante (Spain)

2008

Spatial patterns of soil surface components (vegetation, rock fragments, crusts, bedrock outcrops, etc.) are a key factor determining hydrological functioning of hillslopes. A methodological approach to analyse the patterns of soil surface components at a detailed scale is proposed in this paper. The methods proposed are applied to two contrasting semi-arid Mediterranean hillslopes, and the influence of soil surface component patterns on the runoff response of the slopes was analysed. A soil surface components map was derived from a high resolution photo-mosaic obtained in the field by means of a digital camera. Rainfall simulation experimental data were used to characterise the hydrologica…

Soil erosion and hydrology of the western Mediterranean badlands throughout rainfall simulation experiments: A review

2013

Abstract Rainfall simulation experiments are widely used in geomorphological research in badland areas. This technique contributed significantly to our understanding of badland geomorphology in the Mediterranean belt. Due to the different types of simulated rainfall applied and the variable size of the plots a review of the State-of-the-Art is necessary. This study confirmed that rainfall simulations are well suited to (i) analyse runoff-infiltration processes and sediment detachment within badlands, and (ii) to establish the factors determining the hydrological and erosion response at interrill scale in badland areas. The hydrological response of badlands is characterized by rapid response…

Comments on “Predicting the Effect of Rock Fragments on Saturated Soil Hydraulic Conductivity”

2007

Root hair anatomy and morphology in Posidonia oceanica (L.) Delile and substratum typology: First observations of a spiral form

2018

Abstract The morpho-anatomical root hair features of P. oceanica ramets collected in meadows settled on different substrata (sand, matte and rock) were analysed. On each substratum, nine plagiothropic rhizomes each one composed by 3–6 interconnected short shoots were collected between April and May 2016 at 10 m of depth. On sand and on rock, the adventitious roots showed two distinct tubular and spiral-shaped hairs, clustered in yellowish-gray gelatinous pads. Tubular root hair tips were dactiliform and generally attached to grains of rock fragments. Moreover, a sub-circular swelling zone occurred. On matte , root hairs did not form gelatinous pads, were very short and had a simple distal p…

Ceramic production at Selinunte (Sicily) during the 4th and 3rd century BCE: New archaeometric data through the analysis of kiln wastes

2018

Abstract A set of 37 overfired ceramic samples was collected from the dump of two kilns sited in the productive area FF1 in the acropolis of Selinunte (south western Sicily), being specifically active in the period 409–250 BCE. The ceramic samples were analysed by thin-section petrography and chemical analysis, with the aim to establish a valuable ‘reference group’ representative of the ceramic produced at Selinunte during the Punic phase. The petrographic and chemical analyses allowed to state that the ceramic manufactures from the kilns operating in the FF1 insula are characterized by rather homogeneous textural/compositional features. The daily-use common ware here produced is characteri…

X-ray CT analyses, models and numerical simulations: a comparison with petrophysical analyses in an experimental CO<sub>2</sub&a…

2016

Abstract. An essential part of the collaborative research project H2STORE (hydrogen to store), which is funded by the German government, was a comparison of various analytical methods for characterizing reservoir sandstones from different stratigraphic units. In this context Permian, Triassic and Tertiary reservoir sandstones were analysed. Rock core materials, provided by RWE Gasspeicher GmbH (Dortmund, Germany), GDF Suez E&P Deutschland GmbH (Lingen, Germany), E.ON Gas Storage GmbH (Essen, Germany) and RAG Rohöl-Aufsuchungs Aktiengesellschaft (Vienna, Austria), were processed by different laboratory techniques; thin sections were prepared, rock fragments were crushed and cubes of …

Micro-scale post-fire surface cover changes monitored using high spatial resolution photography in a semiarid environment: A useful tool in the study…

2012

[ES] Although post-fire soil erosion has been studied, little attention has been paid to changes in soil surface cover following fires, despite this being a key factor in understanding the water and sediment yield. This study, at Peñaflor (Spain), investigated the effect of fire on soil erosion using data from soil erosion plots and high spatial resolution photography (HSRP). Measurements were made from October 2003 to October 2005 in a control plot and a plot experimentally exposed to a fire in October 2004. Ground cover components were identified, including vegetation, bare soil, stones, charcoal and ash. Runoff and sediment concentrations were low because of the absence of intense rainfa…