various technique,equipment's and processes are required. Geological Mapping, Soil Geochemistry,Ground Magnetics, drilling and sample collection are some of the important technique's exploration Geologist use. The data acquired on the field can be used to produce contoured element distribution map. These maps can be used to relate the underlying geology. Data taken from Mt Bulga is used for soil geochemistry and geological mapping. A. Metal commodities Cu, Pb, Zn. Complete contour geochemistry maps for Cu and Pb and compare with the contoured map of Zn provided below. Discuss the distribution and relationship with geology (rock types, faults, mining areas)and/or topography. Give reasons for the zonation of Cu-Pb-Zn. concentration is found at the fault line between Felsic volcano and Mafic Bing volcano. High Pb concentration can be found between Felsic volcano (mullions Range) and Shale- phyllite near the northwest mines. Sericitic alteration could be seen at around Pb 505-247 ppm mark, which suggest strong Pb, Zn anomaly. Cu,Pb and Zn are distributed by temperature gradient. Zn and Pb form at lower temperature whereas copper forms at higher temperature. Because of this P band Zn concentration is higher towards North west and Cu concentration(ppm) is higher at the centre. The Mines are located at the fault which contains metals like Cu, Pb, Zn, Fe. Looking at the Cu Geochemistry map we can see a trend going from the North to south. Cu, Pb, Zn are mafic thus they are zoned together.B. Examine the soil geochemical maps of Fe and Ca below and relate to the underlying geology. What rock types are the compatible elements (Fe, Mn, Cr, V,Ti, Ca, Sr) commonly associated with and what minerals are they accommodated in?From the Soil Geochemistry map, we can see that that High concentration of Fe and Ca are found towards the south. They follow similar pattern and thus are heavily concentrated towards the bottom of the map. From the map we can say that the area with high Fe, Ca concentration must be Mafic. With this the underlying geology must be from Mafic volcano (Byng Formation). From this we can also say they contain massive sulphide. These compatible elements are commonly associated with mafic rocks. They are associated with Diorite,Anorthosite, norite. Mafic rocks often contain Ca rich variety of plagioclasefeldspar. They are commonly accommodated with Syngenetic fine grained pyrite-galena-sphalerite-chalcopyrite-pyrrhotite. We can also see Pyrite-chalcopyrite-pyrrhotite in mineralised volcanics. Comparing Fe, Ca soil geochemistry map to Mt Bulga geological map we can clearly see that Fe, Ca concentration is high at Mafic volcanic (Byng formation). This is a positive result as Fe and Ca are associated with mafic minerals. Some anomaly can be seen on Fe map as it shows Fe concentration on Mullions range volcano. C. Compare the contoured results of Fe and Ca with your contoured map for Cr.Given that Cr is the least soluble and therefore least mobile of these elements which of these elements would be best in terms of identifying subsurface geology and differentiate between mafic and felsic volcanic rock types and why?Comparing Cr map to Fe and Ca we can see that they have close spatial correlation. Cr concentration is much higher towards the Byng volcanic. It extends form Byng volcanic towards north. The concentration of Cr is lower once it gets closer to Mullions range. This holds true for all three maps as all of the mare Mafic. The concentration of Cr is particularly higher where Diorite is present.Cr is least soluble and therefore Immobile and has a tight boundary. In terms of identifying sub surface geology Cr would be better because Cr is mafic and often found as iron chromium oxide. Magnesium can substitute for iron in variable amounts as it forms a solid solution with magnesiochromite. It occurs in Mafic and ultra mafic rock intrusive rocks. It is commonly associated with olivine,magnetite and basalt which are all mafic. The second reason is that since its least soluble and immobile it wont leach off during rainfall. Mafic volcanic rock types are rich in Iron and magnesium along with calcium where as felsic volcanic rock types are rich in feldspar, silicate. Mafic rock types are more alkaline where felsic rock types are more acidic.D. Compare the Ca contour map above with your contour map of Sr. Is there a close spatial correlation between the two elements? Why? - Hint - Sr has similar properties to Ca and easily substitutes for Ca in Ca-bearing minerals. What rock types and minerals host Ca in the basement geology at Mt Bulga?Yes, comparing the Ca contour map to Sr contour map there is a close spatial correlation between two elements. This is because Sr is compatible element and it has similar property to Ca thus it substitutes Ca in Ca-bearing minerals. Sr concentration is high towards Mafic Volcanic range. Soil geochemical map suggest that some anomaly as we can find medium concentration of Sr towards Mullions range. The concentration of Cr is very high at the Godolphin fault in between Byng volcanic and Mullions volcanic range. It is also similar to Plagioclase and may sometimes host Ca in plagioclase. Rock types such as Pyroxene, hornblende host Ca in basement geology at Mt Bulga.E. What rock types are the incompatible elements (Zr, Rb, Th, K) commonly associated with? Why?Incompatible elements (Zr, Rb, Th, K) are commonly associated with Alluvium,and felsic volcanic range. They are associated with Felsic rock types and are rich in silicon, potassium, aluminium, oxygen. Common felsic mineral include quartz,orthoclase.F. Compare the contoured results of K and Rb with your contoured map for Zr.Given that Zr is extremely insoluble and therefore least mobile of these elements which of these elements would be best in terms of identifying subsurface geology and differentiate between mafic and felsic volcanic rock types and why? Comparing the contoured results of K and Rb with Zr there does not seem to be any spatial correlation between them. There is high Zr concentration found toward Mullions Volcanic range where as there is low Zr concentration at Shale-Phyllite (Arson Formation). We have High Zr value as it is present in high number in Felsic element such as quartz. K and Rb would be best in terms of identifying subsurface geology and differentiating between mafic and felsic volcanic rock types. This is the case because we can see Zr in mafic rock as well but In case of K and Rb they are in high concentration in felsic rock.G. Soil pH - what rock types are acidic verse alkaline soils associated with?Which sulphide species are present in ores at Mt Bulga? Is there any evidence of acid rock drainage around the Mt Bulga workings? Felsic volcanic create much more acidic soil compared to mafic volcanic. Mafic volcanic are rich in calcium which tends to create more alkaline conditions. Yes there is evidence of acid rock drainage around mount Bulga. The limestone drainage has worked perfectly which has stopped acid drainage from seeping into water source or contaminating nearby soil.H. How are they managing acid rock drainage at Mt Bulga?They have created limestone drainage at Mt Bulga which captures any acid mine drainage, which neutralizes it and precipitates out the copper rather than letting it go into the creek or nearly land. 2) Given that the diurnal variation at Mt Bulga is in the range of 10's of y and taking into consideration the variations in magnetic intensity between different rock types (mafic Byng volcanics verse felsic Mullions Range volcanics), is it worth correcting the data for diurnal drift or regional gradients on a small prospect-scale magnetic survey as at Mt Bulga? Why?No, it is not worth correcting the data for diurnal drift or regional gradients on as mall prospect- scale magnetic survey as at Mt Bulga. As the magnetic data we got form the field was same with very little to no variation.3) Data reduction (profile smoothing). Data can be smoothed to reduce the impact of"noise" or anomalous outliers such as nearby metal objects or vehicles by applying statistical running averages. Check each profile and note whether there are any obvious artefacts that should be "smoothed". Check the transect that intersected the power lines.What was the affect of the power lines on the magnetic intensity? Readings taken near the power lines were observed to fluctuate wildly from very high to very low. Why might this be the case given that the power lines are probably AC (alternating current)? How should you treat this magnetic anomaly beneath the power line when interpreting the geology? You should also consider the trend of the power lines when undertaking the contouring.The power line and other metal objects do affect the magnetic data. Metal fence and power grid/ power line fluctuate the magnetic by small amount. As the name suggests alternate current periodically reverses direction thus different values are observed. This data can be soothed by taking multiple data from the same point at variable time. Also taking points nearby the power line and on the power line can help smoothed the data.5) Explain how the variations in magnetic intensity relate to the underlying geology. What are the approximate values in gamma (give and average or a range of values) for;a. mafic Byng volcanics,Mafic Byng volcanic, contains mafic rock / minerals such Fe, Mn, Cr, V, Ti, Ca,Sr. they have high magnetic intensity compared thus giving high magnetic value.They range from 57200 to 57900 b. Felsic Mullions Range volcanics Mullions Range contains Felsic rock / mineral have less iron/magnesium and more silicon and aluminium thus have less Average magnetic value. They range from 57100 to 57300c. shales of the Anson Formation shale of an Anton formation are less magnetic as they do not contain Fe/Mg. they range from 57100-57190 Red in shale is pyrite d. ore zone beneath the Mt Bulga workings Variations in magnetic intensity can relate to underlying geology ore zone beneath Mt Bulga. The magnetic intensity can vary form different rock types thus helping us map the underlying geology.6. 6) Is there any indication from the profiles of which way the ore zone might be dipping? o Looking at the profile its dipping towards the west.7. 7) Is ground magnetics a useful exploration tool at Mt Bulga? Why?o Yes, ground magnetic is a useful exploration tool at Mt Bulga. This is because it helps us understand the underlying geology. This also helps with identifying different Volcanic range formation. 3. Reflective Learning Journal Write a 1-2 page reflective journal identifying 2-4 critical learning events that occurred on the field trip to Orange or during the course of this subject. Use the following table to guide your response. Identify 1) What you learnt, 2) How you learnt it, and 3) Why this learning was important. different because of the uneven surface. Repeatedly taking the strike and dip measurement help with the learning process. Learning this skill was very important. Taking Strike and Dip measurement is very important for an exploration geologist as it is one of the basic skill. For strike and dip measurement I think more hands on experience would be helpful for learning this skill.Another skill I learned was following the step for finding the mineral. Although I might not get the correct answer but I found out following those steps were more important for an exploration Geologist. Few other things that I found very helpful was learning what a Mining geologist would do. Although this helpful because it helped me plan for future. I also learned that sometimes it better to take Digital recording in the field so that we can refer back to it later. Taking a digital picture along with a quick sketch helps make the field note better. Even taking audio recording is helpful as we can refer back to it later. Reflection this is a previous work you need to make it related to COVID 19 as we could not made the field, they only provide us data.During the Field trip to Orange I had many learning opportunities but the most important one that I found was 'what it meant to be an exploration geologist'. I learned about how to distinguish minerals in the field, how to take field notes(rubbing the sample and scrubbing it on the Note book itself for colour).Before going to the Field trip I thought that we had to know what each mineral sand rocks were, their properties and differentiating them based on initial look but during the field work I found out that its important to follow the procedure on labeling the minerals than getting it right on the spot. I learned how to follow the outcrop and see the underlying geology. I also learned how to take strike and dip measurement and differentiate between bedding and foliation. I learned how to take strike and Dip measurement by using the mobile application and getting hands on experience. Learning this in class and applying it in the field was Looking at the Cu, Pb, Zn map bellow we can see pattern of a sort. Comparing Cu to Zn we can see that Zn is more abundant. Cu and Zn concentration are mostly found between felsic and mafic at Godolphin fault veining. Comparing the Geochemistry map to Mt Bulga geological map we can see that Pb, Zn and Cu
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