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New developments on high-resolution identification of interface events at sediment rocks with X-ray fluorescence (XRF) elemental and physical properties logger tools and their efficient usage
Dursun Acar, Memet Namik Cagatay, Can Genç, Kadir Eriş, Erol Sari, Sefer Örçen, Ozlem Makaroglu, Sena Akçer, Demet Biltekin

Building: Muséum d'Histoire Naturelle de Genève
Room: Lobby /Hall/
Date: 2018-12-05 10:56 AM – 10:59 AM
Last modified: 2018-11-30

Abstract


Element records of wet and dry sediment samples or fossil shells show intense count rates with their high concentrations in sediments as primer factor at natural settlement ambiance. Second important count rate factor is focused to geometry of sediment layers which earned lateraly related with basin gravitational and tectonic mass displacements as in seismic events, even sample preperation deformations during field sampling is included to this second classification. Third generalization covers storage and measurement conditions at the before and during laboratory works. All of that factors efficent on value changings. For relative value gain Copper (Cu), Carbon (C) and Aluminium (Al) slits can be used on elemental measurements for eliminate effects of neighbour shell coils for fossils and angular lineation of sediment layers. They provides continious calibration control for more sharp element identification at measurements. Carbon slit usage proved how important on comparative density measurement between Gamma and X-ray density because high carbon concentration on sediments by reason of Carbon’s high X-ray absorbent specification shows more high density results than sediment’s natural state. Physical conditioning of brittle or soft samples need preparings with undisturbed form before measurements. By the way of slit usage provides restricted exposure area on sediment and fossil for penetrative rays, thus values obtained with high precise by same standart sliced sample as more convenient form than main sample.

About elemental measurements (Xrf): ED- XRF was performed both for fossil shells and thin layered sediments with slit usage on "length around sub mm " laminas. The proxy elements, which are indicative for the event separation in sedimentary processes, have become clearer about elemental count rates as more evident from distinctive localization. Weak or strong detectable chemical elements gives advantages for interpretation of events when their "measurement activator ray" focused or restricted with reference slits. Thus very thin as mm scale sediment samples improved the count results as processed under physical enrichment without high computational efforts on detector, even the trace elements won the powerful proxy features at their time-position. At the results, element Sulfur (S), Calcium (Ca), Potassium (K), Chlorine (Cl) counts enriched with both wet and dry thin film samples. High counting rates of Zinc (Zn) and Barium (Ba), Chrome (Cr), Silicium (Si), Mercury (Hg) performed only with dry film sample.

About physical measurements: Original physical aspects of sediment was tested and compared with calibrations at lamina including layers of same sample about count rates on until to thinned artificial form. Different humid conditions and cross axis measurements were changed the interpretation of density in angular forms. Different axis measurements help to make geometric corrections. High accuracy mass density, magnetic susceptibility, and other chemical measurements need to consideration of layer angularity and volumetric mass effects, otherwise, collected geologic records can be wrong reference for future works as 'content accuracy'. New important helpful methods were developed by sensor's focused magnetic field with less neighbour sediment layer effects. Significant high data peaks were provided with low volumetric mass of sample unlike to conventional half or U formed sediment core on both physical and chemical measurements.

Measuring of physical and chemical parameters for the same sample on different direction can caused some important points, explained as follows; Density, Electrical Resistivity, Magnetic Susceptibility and ED-XRF chemical element analyses can give different results belong to sedimentary matrix linearity by particle shape and shear linearity from basin deformations, different water currents, mass gravitational movements, and also by rectifier effect of earth's paleomagnetic remnants and lab measurements under effect of today’s magnetic North direction.