An Experiment Research On The Methodology Of In Situ X-ray Fluorescence Scanning Analysis

The development of X-ray fluorescence(XRF) core scanners offset drawbacks ofthe traditional XRF analysis, which not only has opened the way to in-situ andon-line measurement of geological materials, but also allows rapid collection ofhigh-resolution continuous records of elemental distributions. Those advantagesmakes in-situ XRF analysis become increasing popular in high-resolution research ofboth paleoenvironment and paleoclimate. However, the problems in the applicationlead us to do research on the methodology, in order to improve qualification of thismethod in the scientific research. This article conducted a research on methodology,and this provide bases for scientific research.First of all, X-ray fluorescence (XRF) is a well-established analytical techniquefor estimating the elemental concerntration by XRF intensity. The XRF intensity ofelements is influenced by sample types, X-ray tube and count time, but there lacks aset of robust experiments method. So in this article,based on the elements reflectingthe information of paleoenvironment and paleoclimate, the author conducted aresearch on a set of measurement condition test for mudstone, limestone and silicaliteon the ITRAX core scanner which is manufactured by COX analysis company inSweden, and primarily established the optimum measurement condition of the threekinds of sedimentary rocks.In addition，although the rapid, non-distructive and high-resolution output of theXRF core scanner offsets drawbacks in the traditional XRF analysis and it hasbecome increasingly in research of both paleoenvironment and paleoclimate, theinhomogeneity of the core (desity, surface elevation, grain size, mineral compositionand porosity) can affect the XRF results, and make it impossible to obtain quantitativemeasures. So we need to calibration all the factors to achieve absolutely quantitativeanalysis.This article selects a6m-long sediment core retrieved from Songliao basin, NEChina,from Cretaceous records. Compared in-situ XRF measurement with traditionalXRF quantitative results, the author proposes a model called log-ratio calibration equation for XRF core scanners, which successfully applys in the ratio of elementsconcentration, bringing out the quantization for the element record as a paleoclimateproxy, and underline the element quantitative analysis. This progress will also expandthe Fields of the core scanners.