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Paleostress and Remote Sensing Analysis of Brittle Fractures from the Eastern Margin of the Dead Sea Transform, Jordan”

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Masaryk University Faculty of Sciences Department of Geological Sciences “Paleostress and Remote Sensing Analysis of Brittle Fractures from the Eastern Margin of the Dead Sea Transform, Jordan” ―Literature Thesis in Requirement for Doctor of Philosophy in Geology Degree Program‖ Prepared by: M.Sc. Omar Mohammad Radaideh Supervisors: Assoc. Prof. RNDr. Rostislav Melichar Brno, Czech Republic 2013 OUTLINES CONTENTS ……………………………………………………………...……………………… II LIST OF FIGURES………………………………………………………………………………. III LIST OF TABLE…………………………………………………………….…………………… III CONTENTS PAGE 1. INTODUCTION 1 2. GEOLOGICAL AND TECTONIC SETTING 2 2.1 General Geological Overview 5 2.2 Major Tectonic Elements 3. SIGNIFICANCE AND OBJECTIVES OF THE STUDY 7 4. METHODOLOGY 8 4.1 Paleostress 8 4.2 Remote Sensing 13 4.2.1. Linear stretching 16 4.2.2. Principal Components Analysis 16 4.2.3. Band ratios 17 4.2.4. Edge Enhancement 17 4.2.5. Intensity/Hue/Saturation (HIS) transformations 18 5. PREVIOUS STUDIES 19 5.1. Paleostress Analysis in Jordan 20 5.2. Paleostress in the Sinai-Israel Sub-Plate 22 5.3. Paleostress in the East Mediterranean 25 5.4. Summary of Paleostress Results 28 REFERENCES 28 II LIST OF FIGUERS Figure Page Figure 1: Location map of the study area…………………………………………………………… 1 Figure 2: Simplified geological map of the southwestern Jordan……………………………...…… 3 Figure 3: The Main tectonic features of the Dead Sea Transform………………………………….. 6 Figure 4: Generalized structure map of Jordan……………………………………………………... 7 Figure 5: Schematic flowchart illustrating the methods and steps that will be used in this study….. 8 Figure 6: Stress ratio and stress ellipsoid…………………………………………………………… 9 Figure 7: The relationship between stress and ideal faults………………………………………….. 10 Figure 8: Types of stress regimes…………………………………………………………………… 11 Figure 9: Worksheet window for entering the data to the Mark 2010 Program…………………….. 12 Figure 10: Criteria for determining the sense of motion on a fault surface…………………………. 13 Figure 11: The studied area, covered by four SRTM-DEM images ……………………………….. 15 Figure 12: The studied area, covered by four ETM+ images. ……………………………………… 15 Figure 13: Example of linear stretching, where pixel values 58-158 are stretched to 0-255……….. 16 Figure 14: First and second principal components………………………………………………….. 17 Figure 15: Principles of edge filter operation……………………………………………………….. 18 Figure 16: Coordinate system for the intensity, hue, and saturation (IHS) transformation………… 19 Figure 17: Synthesis of the major tectonic events in Israel and surrounding regions………………. 25 Figure 18: Shortening phases in southern Turkey…………………………………………………... 27 LIST OF TABELS Table 1: A geological column of the study area……………………………………………………. 4 Table 2: Paleostress direction (SHmax) in Jordan, Syria, Sinai-Israel, and south Turkey………….. 28 III 1. INTRODUCTION Jordan is situated in the north-western corner of the Arabian plate between the stable part of the Arabian Plate and the unstable area of the Dead Sea Transform (DST). It has lateral variation in layer thickness and facies. The Arabian Shield basement is exposed in southwest of Jordan near of Aqaba Gulf (Edgell, 1992; Alsharhan and Nairn, 1997; Abed, 2000). The structural pattern of Jordan is affected by Miocene to recent opening of the Red Sea and the Dead Sea Transform (DST) fault system. The DST is a sinistral wrench fault and part of the 6000 km long Afro- Arabian rift system, forming a transform boundary connecting the Red Sea with the Taurus- Zagros collision zone. It is considered to be a plate boundary between the Arabian plate in the east and the Israel-Sinai sub-plate (part of the African plate) in the west (Garfunkel, 1981; Edgell, 1992; Atallah et al., 2005). The study area is located in the east margin of the Dead Sea transform (Figure 1). It covers an area about 10644 km2 and includes sedimentary, metamorphic and igneous rocks, ranging in age from Precambrian to Quaternary age. The study area is characterized by numerous fault trends and different orientation of fractures. Figure 1: Location map of the study area. 1 The regional tectonics of the Arabian plate (including Jordan) has been studied throughout macrostructures by many authors, but few analyses of the regional tectonics based on mesostructures were conducted. This study will integrate paleostress analysis based on the fault slip data in combination with Geographic Information system (GIS) and remote sensing to enhance our understanding of the structural and tectonic evolution of the east margin of the Dead Sea Rift. Moreover, recent satellite images will be used to characterize the spatial trends of lineament. It is hoped that the integration of satellite–based lineaments analyses from enhanced satellite imageries with fault slip data will provide more insight into the regional structure and tectonics of the study area. 2. GEOLOGICAL AND TECTONIC SETTING 2.1. General Geologic Overview The study area incorporates exposures of sedimentary, metamorphic and igneous rocks, ranging in age from Precambrian to Quaternary (Figure 2). The Precambrian and Palaeozoic units are only exposed in south area and in small parts along the Wadi Araba-Dead Sea-Rift. The Precambrian basement is part of the Arabian-Nubian shield (Rashdan, 1988; Petters, 1991; Al- Hwaiti et al., 2010) and divides into the Aqaba and Araba complexes. These complexes include various granites, diorites, pegmatites, aplites, rhyolithes and metamorphic rocks (Bender, 1968; 1974; 1975). The plutonic rocks are intruded by a vast number of intermediate to basic dykes. The orientation and concentration of dykes depend on availability of weakness zone such as fractures and joints in the rocks (Rashdan, 1988). Palaeozoic clastic sediments overlie the Precambrian Basement with Pre-Saq unconformity, and comprise of the Salib, Burj, Umm Ishrin, Disi, and Umm Sahm formations (Table 1). The Devonian, Carboniferous and Permian ages are not exposed in Jordan (Sharland et al., 2001; Bender, 1968; Bender et al., 1968; Bender, 1974; Barjous, 1992; Rabba, 1994). Triassic and Jurassic deposits are not present in the study area. The Cretaceous overlay the Palaeozoic sediments after a slight angular unconformity created by uplift and erosion during the Jurassic (Bender, 1968; 1974; Amireh, 1997; 2000). The Cretaceous deposits of the area comprise of the Kurnub Group, the Ajlun Group, and most of the Belqa Group (Table 1). The groups are separated from each other by regional unconformities (Powell, 1989; Powell et al., 1996). The Kurnub Sandstone Group (Early Cretaceous) exposes along many 2 scarps and valleys, and consists mainly of white, pale yellow and pink to multicolored, medium to coarse grained quartzose sandstone, with rounded quartz granules and pebbles (Powell, 1989). The Ajlun Group (Early Cenomanian to Turonian-Coniacian) comprised of (in ascending order) Na‘ur, Fuhies, Hummer, Shuayb and Wadi As Sir formations. Generally, the Group consists of fine grained sandstone, calcareous siltstone, green-red mudstone, micritic limestone, yellow-tan marl and interbedded with harder beds of shelly micritic and dolomitic limestone (Powell, 1989). The Ajlun Group is overlain by the Belqa Group. The Belqa Group (Upper Cretaceous to Middle Eocene age) consists of Wadi Umm Ghudran, Amman Silicified Limestone, Al Hisa Phosphate, Muwaqqar Chalk Marl and Umm Rijam Chert Limestone (Powell, 1989). The Balqa Group consists mainly of massive bedded chalk, chert, limestone (micrete, microcrystalline, oyster-shell grainstone types), chalky limestone, phosphate and dolomitic marl. Cenozoic sedimentary deposits are covered many parts of the study area, spatially in the Dead Sea Rift. It consists of clay, marl, gypsum crystals, pleistocene fluviatile deposits, alluvial sediments, alluvial fans, and Wadi sediments (Powell, 1989). Figure 2: Simplified geological map of the southwestern Jordan, modified from Strijker (2013). 3 Table 1: A geological column of the study area (compiled from Bender (1974; 1975), Rashdan (1988), Powell (1989), Powell et al. (1994) and NRA (1995)). Period Age Formation Description Era Group Holocene Alluvial fans , Wadi Unconsolidated sand, silt, clay and Quaternary (Recent) and lake sediments gravels Pleistocene Lisan Pliocene Neogene Gypsum, conglomerates, marl, clay, Miocene Valley n Undifferentiated gravels, fine silt and clay. Cenozoic Oligocene Jorda Paleogene Tertiary Eocene Umm Rijam chert Paleocene Muwaqqar chalk marl Massive bedded chalk, chert, limestone Maastrichtian (micrete, microcrystalline, oyster-shell grainstone types), chalky limestone, Al Hisa phosphorite Campanian Belqa phosphate and dolomitic marl. Amman Silicified Santonian Wadi Umm Ghudran Torronian Wadi As Sir Shuayb Fine grained sandstone, calcareous siltstone, green-red mudstone, micritic Cretaceous limestone, yellow-tan marl and Hummer Cenomanian Ajlun Mesozoic interbedded with harder beds of shelly Fuhies micritic and dolomitic limestone. Na‘ur Albian White, pale yellow and pink to multicolored, medium to coarse Aptian Kurnub grained quartzose sandstone, with Neocomian rounded quartz granules and pebbles Middle Silurian Khushsha Early Alternating cycles of fine- to medium- Late Mudawwara grained quartz arenite, mudstone and shale Middle Khrayim Dubaydib Ordovician Hiswa Early Umm Sahm Paleozoic Late Cambrian Disi Coarse arkosic sandstone, mature Late Middle Umm Ishrin quartz-arenite, dolomite, shale, Cambrian Ram siltstone and pebbly conglomerate Early-Middle Burj Early Salib Araba complex Various granites, diorites, pegmatites,
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  • Significance of Fracture Patterns in a Rock Mass During Excavation by Blasting in Bandhagen, Sweden

    Significance of Fracture Patterns in a Rock Mass During Excavation by Blasting in Bandhagen, Sweden

    Examensarbete vid Institutionen för geovetenskaper Degree Project at the Department of Earth Sciences ISSN 1650-6553 Nr 332 Significance of Fracture Patterns in a Rock Mass during Excavation by Blasting in Bandhagen, Sweden Betydelsen av ett sprickmönster vid utschaktning av berg genom sprängning i Bandhagen, Sverige Mattias Ryttberg INSTITUTIONEN FÖR GEOVETENSKAPER DEPARTMENT OF EARTH SCIENCES Examensarbete vid Institutionen för geovetenskaper Degree Project at the Department of Earth Sciences ISSN 1650-6553 Nr 332 Significance of Fracture Patterns in a Rock Mass during Excavation by Blasting in Bandhagen, Sweden Betydelsen av ett sprickmönster vid utschaktning av berg genom sprängning i Bandhagen, Sverige Mattias Ryttberg ISSN 1650-6553 Copyright © Mattias Ryttberg and the Department of Earth Sciences, Uppsala University Published at Department of Earth Sciences, Uppsala University (www.geo.uu.se), Uppsala, 2015 Abstract Significance of Fracture Patterns in a Rock Mass during Excavation by Blasting in Band- hagen, Sweden Mattias Ryttberg When excavating a rock wall by blasting, pre-existing structures in the rock has a strong impact on the stability of the wall. For excavation in Bandhagen in Stockholm, the nature and orientation of the pre- existing geological features, namely fractures, were not taken into consideration before excavation begun. Geological field studies were carried out in order to investigate the possibility of a more favorable outcome than in the Bandhagen case. Mapping conducted in March 2015 was focused on fracture distribution and the results showed two sets of open shear fractures with fresh surfaces. The first set of the fractures cross-cuts the wall with a strike of NNW-SSE and dips between 70°±30°.