The Foundation of the AIPG Needs Your Support
The Foundation of the American Institute of Professional Geologists needs your support. Needless to say, 2020 has been a very different and surreal year for many of us. For several years, the Foundation has held a silent auction at the welcome reception of AIPG’s national annual meeting. The silent auction not only served as a fundraiser but is also an opportunity to promote the Foundation so that students and members know better what the Foundation has supported in the past few years. Since the annual meeting was post- poned to October 2021, we were not able to hold the silent auction. This year we need to rely even more on the financial commitment from AIPG members and others who are able and interested in contributing to the Foundation. Every donation helps the Foundation to provide support toward building the future of geology. The Foundation supports a variety of programs of the AIPG: student scholarships, student and young professional workshops, educational programs aimed at practitioners, the public, and policy makers, and some special needs that may be requested by AIPG or other professional or educational organizations. The Foundation is proud to be able to serve AIPG and the geosciences by providing financial support for these programs. If you have any questions or comments about the Foundation, please contact me or any of the other Trustees of the Foundation for additional information.
Be sure to check the Foundation web page on the AIPG web site
https://aipg.org/page/Foundation for information on awarded student scholarships and the list of donors. Your continued support is greatly appreciated. Thank you.
Barbara Murphy, RG, CPG Chairperson, Foundation of the AIPG 480-659-7131 office phone;
bmurphy@geo-logic.com
The Foundation of the American Institute of Professional Geologists is a 501(c) (3) organization. Contributions are tax deductible. EIN 45-2870397
The north-south trending, en-echelon faults are the second prominent structural feature of the Lovitt mine (Figure 4). Three main NS faults identified are the N-S Fault, the 49 Fault, and the Unnamed Fault. It should be noted that in the North Drift detailed underground sampling and mapping (Early Mining History-Nellies Room) show splays of the 49 Fault that appear to become conformable with the Footwall Fissure. This observation gives credence to Ott’s 1987 (Ott,
et.al., 1987) model suggesting the intersection of the NS faults and the NW trending ore deposits and structures may have acted as a localization for hot springs activity. These en echelon faults have a N to N10W strike and vertical dip. They are interpreted as strike slip faults with late-stage reverse displacement (Burgoyne, A.A, 1996, Johnson, B., 1991).
Burgoyne, 1996 mentions four small-scale structures recorded from underground mapping at the Lovitt Mine. First, a low angle flat-laying reverse fault striking NW and dipping less than 30 degrees SW. The flat faults offset gold-bearing and barren veins. Second, NW striking, and steep SW bedding plane shears offset veins of all orientations. Third, high-angle NE trending faults offset all veins. Fourth, barren NE striking, SE dipping to NW dipping, and NW striking, SW dipping to NE dipping joints. A few north dipping joints are pyrite filled.
The D-Reef rocks are capped, stratigraphically by the 46.2
±1.8 Ma Compton Tuff (Margolis, J., 1987). The arkosic stra- tigraphy east of the D-Reef dips to the northeast at 35 degrees
8 TPG •
Oct.Nov.Dec 2020
to 50 degrees but increases from 70 degrees to 83 degrees adjacent to the D-Reef forming an overturned fold pattern at the Lovitt Mine. The core of this overturned fold is thought to be the Eagle Creek Fault structure responsible for the gold- bearing fluids pathway (Burgoyne, A.A, 1996). The Oligocene Wenatchee Formation unconformably overlies the Chumstick Formation. The Wenatchee Formation is composed of 1000 feet of fluvial and lacustrine sediments, including a conglomerate unit (upper member), quartz sandstone-shale units (lower member), minor tuffaceous units, and thin coal beds. District scale northeast verging fold and thrusting post-dates the Wenatchee Formation age (Margolis, 1989). (Figure 4).
The pervasive silicification of Chumstick Formation stra- tigraphy and intense jarosite-iron oxide staining of the D-Reef gold deposit defines an erosion-resistant outcropping ridge (Burgoyne, A.A, 1996). The occurrence of gold assays at D-Reef is spatially associated with quartz-adularia veins, breccias, and stockwork with quartz-adularia matrix flooding and cal- cite veins. This mineralization and alteration of the host rocks is pervasive and controlled by sedimentary permeability and joint plus fracture-induced porosity and permeability. A cen- tral core of silicification is enveloped by clay(?)-sericite altera- tion consisting of sericite, illite, and mixed illite-smectite. The sericite alteration intensity varies with degree of silicification. A propylitic halo consisting of pyrite, chlorite and illite sur- rounds the D-Reef alteration pattern with pyrite extending to
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