Institute of Earth Sciences, The Hebrew University of Jerusalem, Edmond J. Safra 5 Campus, Givat Ram, Jerusalem, Israel 6

Transcription

1 GSA DATA REPOSITORY Nanograins Form Carbonate Fault Mirrors 3 Shalev Siman-Tov 1, Einat Aharonov 1, Amir Sagy 2, and Simon Emmanuel Institute of Earth Sciences, The Hebrew University of Jerusalem, Edmond J. Safra 5 Campus, Givat Ram, Jerusalem, Israel 6 2 Geological Survey of Israel, 30 Malkhe Israel, Jerusalem, Geological setting 9 Figure DR1. Locations of studied faults (white stars) and the main fault systems in the area. 1 Kfar Giladi (KGF), 2 Nahal Avinadav fault (NAF) at Revaya quarry, 3 Yair fault (YF) in Ein Bokek region, 4 - Nahal Uziyahu fault (NUF) in Gulf of Eilat. Red: main segments of the Dead Sea transform. Green: margins of the Dead Sea basin and the Gulf of Eilat. Yellow: Carmel-Tirza fault zone. The topographic background of the region is based on Hall (1993)

2 11 Fault surface TABLE DR1. THE STUDIED FAULT SURFACES Location Lithology Fault Sense Displacement exposure (m) at Strike direction Kfar Giladi (KGF) 33 14'29''N 35 33'49''E Eocene limestone * active quarry oblique strike-slip 10s-100s NNE- SSW Nahal Avinadav (NAF) 32 27'13''N 35 26'37''E Eocene limestone active quarry oblique strike-slip # N-S Yair (YF) 31 12'57''N 35 21'24''E Turonian dolomite and Maastrichtian chalk** natural erosion dip-slip ~150 # NNE- SSW Nahal Uziyahu (NUF) 29 39'45''N 34 53'54''E Turonian limestone natural erosion dip-slip ~100 # NNW- SSE * Based on the 1:50,000 geological map and previous studies (Nuriel et al., 2012; Sneh and Weinberger, 2003; Weinberger et al., 2009). It wasn't possible to measure the exact displacement using geological markers, as the rocks around the fault are intensively deformed. Hence, displacement is evaluated by comparing the fault surface roughness to surfaces from previous work (Sagy et al., 2007) and by the existence of a thick (10s cm) cataclasite layer (Sagy and Brodsky, 2009; Scholz, 1987). This shear zone is related to a large segment of the Dead Sea Rift which accommodated at least several kilometers since the Pleistocene (Garfunkel et al., 1981). Based on the 1:50,000 geological map and previous studies (Hatzor and Reches, 1990; Hatzor, 2000). # Displacement values are based on direct measurements of sedimentary layers offset. ** Based on the 1: 50,000 geological map (Agnon and Sagy, 2011). Based on the 1:50,000 geological map (Beyth et al., 2012). 12 2

3 Figure DR2. Light reflectance from two different fault surfaces. Hand samples from 14 NUF (on the left) and from KGF (on the right) show different reflectance of sunlight. 15 Even though both samples look in places very smooth and planar (e.g. marked by 16 black arrows) only the KGF sample is glossy

4 EXPANDED METHODS Roughness Measurements 21 Roughness measurements were performed on samples using atomic force 22 microscopy (AFM; Veeco Multimode 8) and an optical profilometer (ContourGT-K1 23 3D Optical Microscope, Bruker Company). For the AFM measurements, a non- 24 contact self-optimization imaging mode (ScanAsyst) was used; triangular silicon- 25 nitride tips (ScanAsyst-Air; Bruker) with nominal radii of 2-12 nm were employed for 26 all analyses. Scans of 1 1, 10 10, and µm 2 were conducted, each with data points; consequently, scan resolution varied from nm. An area of cm 2 from KGF was scanned using the optical profilometer in slip parallel and 29 perpendicular directions, with horizontal resolution of 3.6 μm Nano and Micro-scale Imaging 32 The surface microscale and nanoscale structures were also studied by high 33 resolution scanning electron microscopy (SEM; Sirion, FEI Company) for carbon 34 coated samples and by extra high resolution SEM (MagellanTM 400L) for non-coated 35 samples. In addition, to explore the interior structure of the fault surfaces, a cross- 36 section foil of the KGF surface, revealing structures down to a depth of 4 microns 37 below the surface, was prepared (Fig. DR3) using the focused ion beam (FIB) 38 technique (DualBeam Helios NanoLab 600). The final nm thick foil was 39 then analyzed using high resolution TEM (Tecnai F20 G2, FEI Company) Figure DR3. Foil preparation using FIB. A thin foil of the KGF surface was obtained 43 by excavating two pits perpendicular to the fault surface; the remaining cross section 44 was later removed using a micro-manipulator. The chosen area was marked by two X 45 signs and covered by platinum layer (marked by Pt). The foil was further milled by an 46 ion beam to a thickness of nm

5 Roughness Analysis Figure DR4. Fault surfaces roughness analysis. The blue (red) points are analysis 51 result of the slip perpendicular (parallel) profiles. At each graph, three colored lines 52 are drawn above the data points with slope β = 2, 3, 4, corresponding to Hurst 53 exponent H = 0.5, 1, 1.5). It can be observed that the slope steepens with decreasing 54 wavelength. A: YF surface, based on three AFM scans (1, 10 and 100 microns side 55 width). B: NAF surface, based on two AFM scans (1 and 10 microns side width)

6 58 REFERENCES CITED Agnon, A., and Sagy, A., 2011, Geological map of Israel, Newe Zohar: Geological 61 Survey of Israel, scale 1:50,000, sheet 16 III,IV. 62 Beyth, M., Eyal, Y., and Garfunkel, Z., 2012, Geological map of Israel, Elat: Geological 63 Survey of Israel, scale 1:50,000, sheet 26 I,II. 64 Garfunkel, Z., Zak, I., and Freund, R., 1981, Active faulting in the Dead Sea rift: 65 Tectonophysics, v. 80, no. 1 4, p. 1 26, doi: / (81) Hall, J.K., 1993, The GSI digital terrain model (DTM) project completed: Geological 67 Survey of Israel current research, v. 8, p Hatzor, Y. H., 2000, Geological map of Israel, Bet She'an: Geological Survey of Israel, 69 scale 1:50,000, sheet 6 I,II. 70 Hatzor, Y., and Reches, Z., 1990, Structure and paleostresses in the Gilboa' region, 71 western margins of the central Dead Sea rift: Tectonophysics, v. 180, no. 1, p , doi: / (90)90374 h. 73 Nuriel, P., Weinberger, R., Rosenbaum, G., Golding, S. D., Zhao, J. x., Uysal, I. T., Bar 74 Matthews, M., and Gross, M. R., 2012, Timing and mechanism of late 75 Pleistocene calcite vein formation across the Dead Sea Fault Zone, northern 76 Israel: Journal of Structural Geology, v. 36, p , 77 doi: /j.jsg Sagy, A., and Brodsky, E.E., 2009, Geometric and rheological asperities in an exposed 79 fault zone: Journal of Geophysical Research. Solid Earth, v. 114, B02301, 80 doi: /2008jb Sagy, A., Brodsky, E.E., and Axen, G.J., 2007, Evolution of fault surface roughness 82 with slip: Geology, v. 35, p , doi: /g23235a Scholz, C. H., 1987, Wear and gouge formation in brittle faulting: Geology, v. 15, no. 84 6, p , doi: / (1987)15<493:wagfib>2.0.co;2. 85 Sneh, A., and Weinberger, R., 2003, Geological map of Israel, Metulla: Geological 86 Survey of Israel, scale 1:50,000, sheet 2 II. 87 Weinberger, R., Gross, M. R., and Sneh, A., 2009, Evolving deformation along a 88 transform plate boundary: Example from the Dead Sea Fault in northern Israel: 89 Tectonics, v. 28, TC5005, doi: /2008TC