Assessment of Experimental Semivariogram Uncertainty in the Presence of a Polynomial Drift

Natural Resources Research - The semivariogram, which measures the spatial variability between experimental data, is generally used as a structural input in all two-point geostatistical procedures....     

The georeferencing of RASAT satellite imagery and some practical approaches to increase the georeferencing accuracy

RASAT Earth Observation Satellite is the second remote sensing satellite of The Scientific and Technological Research Council of Turkey (TUBITAK) Space Technologies Search Institute (TUBITAK Space). Generally, the first step to utilize the satellite imagery in GIS applications is the accurate geometric correction of the imagery. But, the geometric correction process of RASAT images is somewhat difficult due to insufficient orbit data and lack of satellite imagery processing software with RASAT model. Although the geolocation of RASAT images is investigated in some recent studies, subpixel accuracies cannot be achieved. In this study, different geometric correction methods and combination of them are tested with a more interactive workflow that uses the results of other approaches. Results show that these approaches can be used for the geometric correction of RASAT like pushbroom satellite images with insufficient orbit data and better geolocation accuracies can be achieved by different geometric correction approaches.     

An Evaluation of Interpolation Methodologies for Generating Three-Dimensional Hydraulic Property Distributions from Measured Data

The process of attempting to model ground-water systems requires a good understanding of the spatial variation of aquifer hydraulic properties. The capabilities of the more recent innovative flowmeters such as the electromagnetic and heat pulse flowmeters provide the sensitivity to measure ambient flows and pump-induced flows. These flowmeters provide the measurements of pump-induced vertical flows which are analyzed to obtain vertical variations in horizontal hydraulic conductivity, K(z). With discrete areal K-values, K(x, y), and vertical profiles of K, provided by multiwell testing, the essential elements are present to produce a three-dimensional hydraulic conductivity field. The advent of these new flow measuring devices has contributed much to the motivation behind this paper. This paper presents the results of applying deterministic and stochastic methodology to the three-dimensional interpolation of hydraulic properties, specifically, hydraulic conductivity, K. Three of the approaches applied in this paper are deterministic in nature, inverse-distance weighting, inverse-distance-squared weighting, and ordinary kriging, while the fourth is a stochastic approach based on self-affine fractals. All of the methods are applied to measured data collected from 14 wells at a site in the United States near Mobile, Alabama. The three-dimensional K-distributions generated by each of the methods are used as inputs to an advective based transport model with the resulting model output compared to a two-well tracer study run previously at the same site.     

A Hybrid Logistic Regression: Gene Expression Programming Model and Its Application to Mineral Prospectivity Mapping

Natural Resources Research - Mineral prospectivity mapping (MPM) is a fundamental task in mineral exploration. The logistic regression (LR) method has been widely used as a data-driven tool for MPM...     

Insights into biaxial extensional tectonics: an examplefrom the Sandıklı Graben,West Anatolia,Turkey

West Anatolia, together with the Aegean Sea and the easternmost part of Europe, is one of the best examples of continental extensional tectonics. It is a complex area bounded by the Aegean–Cyprus Arc to the south and the North Anatolian Fault Zone (NAFZ) to the north. Within this complex and enigmatic framework, the Sandıklı Graben (10 km wide, 30 km long) has formed at the eastern continuation of the Western Anatolian extensional province at the north‐northwestward edge of the Isparta Angle. Recent studies have suggested that the horst–graben structures in West Anatolia formed in two distinct extensional phases. According to this model the first phase of extension commenced in the Early–Middle Miocene and the last, which is accepted as the onset of neotectonic regime, in Early Pliocene. However, it is controversial whether two‐phase extension was separated by a short period of erosion or compression during Late Miocene–Early Pliocene. Both field observations and kinematic analysis imply that the Sandıklı Graben has existed since the Late Pliocene, with biaxial extension on its margins which does not necessarily indicate rotation of regional stress distribution in time. Although the graben formed later in the neotectonic period, the commencement of extension in the area could be Early Pliocene (c. 5 Ma) following a severe but short time of erosion at the end of Late Miocene. The onset of the extensional regime might be due to the initiation of westward motion of Anatolian Platelet along the NAFZ that could be triggered by the higher rate of subduction at the east Aegean–Cyprus Arc in the south of the Aegean Sea. Copyright © 2003 John Wiley & Sons, Ltd.