Application of decision trees to the analysis of soil radon data for earthquake prediction

Abstract

Abstract:This study aimed to provide a systematic overview of water sources in the Baikal region and Transbaikalia by the content of radon (Q) and establish regularities in variations of Q values in space and time.We collected and analyzed our evaluations of Q and the available published Q values for many dozens of water sources in the study area (Fig.

Direct measurement of present-day tectonic movement and associated radon flux in Postojna Cave, Slovenia

“…The arithmetic mean of C Rn over the whole period of monitoring is 2380 6 376 Bq m 23 . During this time, no unrest was recorded at Postojna 1 and no effect of the unrest at Postojna 2 on radon level at Postojna 1 can be seen ( (Zmazek et al, 2003). The decrease in C Rn after September 26, 2007 (Fig 7) cannot be paralleled with earthquakes that occurred in the period September 26, 2007to September 29, 2007 because their epicenters were too far away (R/R D between 4.8 and 7.1) although their magnitudes were not so low for the region (M L from 2.1 to 3.1).…”

“…6), C Rn started to decrease and reached very low values towards the end of E11b(x). As for Postojna 1, it is not believed that this decrease coincided with earthquakes that occurred in the period September 26, 2007 to September 29, 2007 because their epicenters were too far away (R/R D between 4.8 and 7.1), although their magnitudes were not so low for the region (M L from 2.1 to 3.1) (Zmazek et al, 2003). Because C Rn (E11b) is significantly higher than C Rn (tot), with C Rn (E11b)/C Rn (tot) 5 1.35, it can be concluded that compression significantly facilitates radon transport, thus increasing its activity in air.…”

Radon as an Earthquake Precursor – Methods for Detecting Anomalies

“…The aim is to identify radon anomalies which might be caused by seismic events. The application of artificial neural networks (Negarestani et al, 2002(Negarestani et al, , 2003Torkar et al, 2010), regression and model trees Sikder & Munakata, 2009;Zmazek et al, 2003;Zmazek et al, 2006) and some other methods (Sikder & Munakata, 2009;Steinitz et al, 2003) have proven to be useful means of extracting radon anomalies caused by seismic events.…”

“…This makes it complicated and, for small earthquakes, often impossible to differentiate between those anomalies caused by seismic events and those caused solely by atmospheric changes. Therefore, the application of theoretical and empirical algorithms for removing meteorological effects is necessary (Choubey et al, 2009;Ramola et al, 2008;Ramola et al, 1988;Torkar et al, 2010;Zmazek et al, 2003). In this chapter, the different approaches to distinguishing between those anomalies in radon time series caused by seismic activity and those caused solely by hydrometeorological parameters are presented and discussed.…”

Radon in Groundwaters in the Baikal Region and Transbaikalia: Variations in Space and Time

“…Во втором случае часть газа находится в полостях трещин и повышение атмосферного давления «выжимает» его в подземные воды, которые переносят радон по разломам к поверхности. Таким образом, вариации величины Р более заметно влияют на радиоактив-ность подземных вод из источников второй группы и в меньшей степени -близповерхностных водо-проявлений из группы I. Следует отметить, что атмосферное давление является одним из ключевых параметров, контро-лирующих концентрацию радона в почвенном воз-духе [Schery et al, 1982;Rudakov, 1985;Zmazek et al, 2003;Spivak, 2010;Adushkin, Spivak, 2014]. Однако связь между объемной актив-ностью почвенного радона и величиной Р, установ-ленная для Прибайкалья, противоположна той, ко-торая представлена в данной статье для содержа-ния радона в подземных водах.…”