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Home My WebLink AboutPrelimResourceAssessmentRptConfidential Do Not Disclose Pursuant to 3 AAC 107.630, AS 40.25.120(a)(4), AS 38.05.035(a)(9), and 11 AAC 84.780, ormat requests that AEA keep the following report confidential and exclude it from public disclosure. Confidential Do Not Disclose «•rr;fi11 Q <tm Mt. Spurr - Initial Resource Report Highlights Geologists from Ormat conducted a field reconnaissance survey of Mt Spurr during the summer of 2009 with an overarching goal of future exploration plan definition. Work done included mapping, rock/soil sampling, geochemical sampling and ultimate synthesis of these data with historical data and survey information. Initial results are encouraging, with new positive indicators for the existence of a viable hydrothermal system at -depth. That said, additional extensive exploration (including geochemistry, geophysics and drilling) is required to confirm and delineate this potential geothermal resource. Report Ormat completed preliminary geochemical sampling of thermal and non -thermal springs at twelve sites within and near our geothermal lease (see Figure 1). Seventeen actual samples were collected (some sites included more than one sample); while most springs were non -thermal (issuing either directly from beneath glaciers or directly from young volcanic deposits south of Crater Peak and east of the Kid Glacier), one set of springs were in fact thermal in character. This one set of thermal springs is located within the north -south trending `Warm Springs Canyon', bounded by the Crater Peak edifice on the east and Crater Glacier on the west. The springs issue from the floor of the canyon (along and within the cold creek) as well as seeping out from the wall of young pyroclastic and debris flow deposits that form the eastern side of the canyon (see Figure 2). With a linear extent of approximately 1.8 km, these warm springs (with temperatures as high as 410C and flows of approximately 10-20 gpm) have chemistry indicative of geothermal fluid input at depth (see Figure 3). While geochemical modeling and analysis is ongoing, preliminary results indicate: • The majority of sampled waters have elevated anion values indicating geothermal input • Silica values are elevated in all the Warm Springs Canyon samples as well as two additional cold springs east of Warm Springs Canyon and one glacial outwash; elevated silica indicates geothermal heating at depth • Boron values are higher than background, though not as high as those values measured directly before the 1992 eruption; boron indicates contact with geothermal fluids • The majority of sampled waters, including cold, warm and glacial waters, have no bicarbonate; indicates a volcanic source • Magnesium and chloride values are very high compared to historical data; probably indicative of multiple -source water mixing and may point towards a disturbed, `young' hydrothermal system post-1992 eruption • Sulfate has significantly increased with time; potentially indicates increased input of magmatic gasses at depth While the majority of the chemistry is encouraging, geothermometry calculations are complicated and ambiguous at present. The extreme Mg values make the alkali geothermometer impossible to interpret and the attendant mixing implied by these Mg values (as well as the other extremely high cation values) make the Si calculation circumspect as well. Page 3 of 6 CONFIDENTIAL Lithologic and structural mapping was also performed in a few limited areas; two sets of large, active faults were identified in canyon -cuts both on the west and east side of the young Crater Peak volcanic flows (see Figure 4). Both faults offset young volcanic material, including lahars, pyroclastic and debris flows (see Figure 5). Hydrothermal alteration at these fault sites was extensive and included argillic to advanced argillic assemblages (smectite, kaolinite, alunite) as well as pervasive pyrite, amorphous silica, chrysocolla, azurite and native sulfur. The alteration was clearly secondary in all locations and not simply syn-volcanic. Preliminary analysis indicates these faults may be related to larger fault structures mapped further to the east (such as the Lake Clarke fault, Capps Glacier Fault or other unnamed structures identified by recent DGGS mapping) and may serve as potential hydrothermal conduits for upflow (these faults coincide with the —40 deg C warm springs and the cold springs with high TDS and conductivity values). Finally, satellite -based lithologic and thermal mapping is in progress; preliminary results indicate several zones of elevated temperature on the southern flanks of Mt. Spurr though these sites have yet to be ground-truthed. All data, including archival USGS/AVO and DGGS information, is continually added to large digital GIS databases for current and future analysis. 0, d �lfte i Rd I 7i V !Explanation i p-ua,a, muntl�ry 1 - • wn ,simple 00.51 I 3 4 SAs �xl mclel9 � C -i Figure 1: Map showing 10 water sampling sites within and adjacent to the Mt. Spurr geothermal leases. An additional two sites are located to the west of this map extent at Pothole and Harpoon Glaciers. Some of the sites shown above have more than one sample Page 4 of 6 CONFIDENTIAL Figure 2: Left: Furthest southern spring in Warm Springs Canyon, -3.8 km south of Crater Peak summit. Right: Thermal waters seeping from the eastern wall of Warm Springs Canyon, -2.5 km south of Crater Peak Summit. ITb Cn,e,take Mal, �$ Gal alpv, cold ou. . apnnds antl wJ'm =.prams Easleo,Cla .adge springs Wnmspar, air19ffi. Erb —M days below @32 emat,., � sulfate Figure 3: Typical geochemical ternary diagram depicting the chloride (CI), sulfate (SO4) and bicarbonate (HCO3) values for all seventeen sampled sites plus eight additional historical USGS samples ranging in age from 1970 to 2005 Page 5 of 6 CONFIDENTIAL Figure 4: Summary geologic map with major preliminary structures indicated including attitudes and alteration assemblages. Structure on this map is hitherto unknown; future mapping efforts will seek to elucidate sense of movement and more extensive spatial cover Figure 5. Left: Major northeast (to possibly southeast) striking set of faults with dips of approximately 75 degrees. Sense of motion unknown. Appears to cut the Quaternary debris avalanche flows of Nye at al., 2005. Right: Southeast striking fault with dip of approximately 60 degrees. Sense of motion unknown. Appears to cut Quaternary pyroclastic flows. Page 6 of 6