ANKARA UNIVERSITY DEPARTMENT of GEOLOGICAL ENGINEERING GEO402 GEOLOGICAL MAPPING SAFETY IN THE FIELD FIELD MEASUREMENTS AND TECHNIQUES

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1 ANKARA UNIVERSITY DEPARTMENT of GEOLOGICAL ENGINEERING GEO402 GEOLOGICAL MAPPING SAFETY IN THE FIELD FIELD MEASUREMENTS AND TECHNIQUES Dr. Koray ULAMIŞ 2017

2 Potential Hazards and Safety Measures Falling rocks: Avoid areas of recent rock fall and/or areas with large overhangs or unstable faces. Wear a hard hat that meets safety standards at all times. Take care not to dislodge rocks onto other people. Many cliffs and slopes become unstable as the weather conditions change, e.g. after heavy rain or as they dry out and heat up in the sun. If the rocks are often unstable observe under what conditions they are least likely to fall and complete fieldwork at these times if possible. Slippery rocks: Algae - covered rocks on the foreshore or stream beds can be exceedingly slippery. Avoid these areas wherever possible, for instance by walking above the high water mark on the beach or well below it where the algae has been scoured away by waves. The area will also tend to be less slippery when the algae - coated surfaces are dry. Uneven surfaces and surfaces covered with boulders: Ensure that you are wearing strong footwear that will protect your ankles, toes and feet, take your time to pick out a good route and ensure that you do not become fatigued and slip. Unpredictable weather: This can easily result in hypothermia, sunstroke or dehydration. Be prepared for the range of possible weather conditions. In hot conditions ensure you have something to cover your head with, sunglasses, sunblock and plenty of fl uids. In winter ensure you wear warm clothing and have good quality waterproofs, which will also protect you from the wind. A warm hat is essential since a signifi cant proportion of the heat that your body generates is lost through your head.

3 Countryside/wilderness code of ethics Take responsibility for your own actions Leave gates and property as you find them Respect other people s privacy and/or cultural sensitivities Do not disturb plants and animals Leave nothing behind Do not hammer or sample unless it is necessary Follow any signs and landowner s instructions

4 MAP Projection of the whole earth surface or any scaled parts on a plane. ( Ancient maps produced for naval exploration and geography has become the main tool for geological investigation through historical and technological developments. SCALE Scale is the ratio of any distance (length) on the map which corresponds to land surface. A map is classified as small scale or large scale or sometimes medium scale. Small scale refers to maps of large regions such as continents or large nations. In other words, they show large areas of land on a small space. Large scale maps show smaller areas in more detail, such as county maps or town plans might. For instance a town plan, which is a large scale map, might be on a scale of 1:10,000, whereas the world map, which is a small scale map, might be on a scale of 1:100,000,000. Most common geological map scales are 1/ and 1/ Total area on a 1/25000 scaled map is 154 km 2, while km 2 on 1/ sclaed map

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6 Map index and codes based on scale Scale Sample map name 1/ H29 1/50000 H29-A 1/25000 H29-A1 1/10000 H29-A-09 1/5000 H29-A-09-C 1/2000 H29-A-09-C-3 1/1000 H29-A-09-C-3-A

7 COMPASS ADJUSTMENT with TOPOGRAPHICAL MAP Grid North : GK Magnetic North : MK Actual North : Line with the star end In order to adjust the compass based on the topographic map; the declination angle must be calculated. Example: Annual declination of the map is +5 (Grid North is on east of Star) Annual declination of the map is +5 (Grid North is on West of Star) The year of the field work is 2018; 6 15 The year of the field work is 2018; 6 15 ( ) x = =6 15 ( ) x (-) = = -4 15

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9 Location of Memlik on 1/ scaled geologic map

10 A sample area on 1/25000 map

11 Same area on 1/1000 plan

12 INTRODUCTION TO GEOLOGICAL COMPASS

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14 Cocla Compass (Dip/Dip Direction Measurement)

15 Freiberg Compass (Dip/Dip Direction Measurement)

16 Azimuth Measurement with North Needle

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18 PRELIMINARY WORK FOR SITE INVESTIGATION Data collection and previous work (DSİ, MTA, İlbank, Afet İşleri, HGK). The aim of such work is to determine the main geological formation(s). Based on the scale, formations include groups, sub-groups, units, etc. Mapping of any formations on a topographical map or any other kind of detailed work will lead to choose several directions before field work. Understanding of topography from a map is the backbone of geologic study. Transportation choices to site, distance to residential areas, planning of nutrition and preparation of emergency tools are other main important elements of a preliminary field work. Last stage before field work is the investigation of Aerial Photography and/or Satellite Images.

19 AERIAL PHOTOGRAPHY and SATELLITE IMAGERY Aerial photos are produced by Air Force of Turkish Army (HGK). Most photos are 1/35000 scaled with gray tone colors. Main benefit of such photos is the use historical images if available. - Morphology - Drainage - Vegetation - Residential area - Geometry of erosion and floods - Formation Boundaries - Tectonics

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21 Same images of 2005 Kuzulu (Sivas) Landslide

22 SATELLITE IMAGERY Iran- Zagros salt dome and anticline

23 Boundary between Australia and Pacific Plates

24 False color image of tectonic structures

25 Determination of Alteration Zones

26 ESSENTIALS of MAP USE

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28 EQUIPMENTS for FIELD WORK Altimeter (altitude meter) is an instrument used to measure the altitude of an object above a fixed level.

29 GLOBAL POSITIONING SYSTEM and DEVICES WARNING!!: Handheld GPS devices determine the location with some error. Please use relevant datum (ED50 or WGS84) to the topographical map. Also double check the coordinate system of map (UTM or degree/min/sec)

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31 Please check your equipment after field work. Mostly geologic hammer/rock pick is used as scale on outcrops and forgotten after measurement

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33 VISUAL INSPECTION Arriving at a large exposure for the first time can be both exciting and daunting. It is often difficult to know where to start so, check whether the exposure is safe and then walk around and view it from different angles before making a decision. One way to tackle a large exposure with different rock types and features is to first of all divide the exposure into units based upon obvious features such as changes in color and weathering characteristics. Decide from a distance what the main characteristics of these units are and consider making a sketch to show these characteristics and their relationship to each other before completing more detailed observations close up. Your preliminary observations of the large - scale features in the exposure should include the following. Nature of the contacts: Note whether the contacts are gradational (e.g. colour change, sharp contact, planar, irregular etc. Lateral changes in thickness: Note the position and amount of any changes. These might relate to processes such as erosion, faulting, fluvial or submarine channels, thinning of a dyke or sill, changes in depositional conditions of sedimentary and extrusive rocks. Cross - cutting relationships: Look for cross - cutting. For instance an igneous body cutting through older strata, erosional down cutting or an angular unconformity. Evidence of displacement and deformation: Look for folding and faults. Angular unconformities: Look for a change in the rock type associated with a change in the bedding orientation.

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35 Elementary Outcrop Sampling: Hand Specimens Is the rock made up of interlocking crystals, or made up of crystals in a fine grained groundmass, or made up of grains within a matrix? If it is composed of grains then it is likely to be a siliciclastic rock or a carbonate but it could also be a pyroclastic rock. If it is crystalline then it could be igneous, metamorphic or one of the less common sedimentary rocks such as an evaporite or recrystallized limestone. What are the major minerals in the rock? Does the rock body show layering? In many cases this is bedding and it indicates sedimentary rocks, lava flows or pyroclastic rocks. Be aware though that a few metamorphic and plutonic rocks can also show layering which may be mistaken for bedding. What is the geometry of the rock body? Both igneous and sedimentary rocks can form dykes and sills but these are relatively uncommon in sedimentary rocks. What is the overall context of the rock body? Metamorphic rocks either form distinct, concentric zones around an igneous body if they are due to contact metamorphism, or more extensive outcrops if they were formed through regional metamorphism. Does the rock show a mineral foliation. If it does it is probably metamorphic, although some igneous rocks show such fabrics. Does the rock show distinct cooling joints? These form only in igneous rocks, although they can extend into the adjacent country rock. Fossils are absent from igneous rocks except for the occasional occurrence in pyroclastic deposits. Fossils are only rarely preserved in low - grade metamorphic rocks and are not found in high - grade metamorphic rocks. More complex bedding structures such as cross -stratification and ripples are confi ned to sedimentary and pyroclastic rocks.