A Field Investigation in the Seward Peninsula, Alaska

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1 A Field Investigation in the Seward Peninsula, Alaska Interim Report of the Possible Impact on the Shallow Ground Water in the Vicinity of Rare-Earth and Uranium and Thorium Mineralization in Alkali Intrusions of the Kachauik District, Seward Peninsula, Alaska by Michael D. Campbell, P.G., P.H., Ted H. Foss, Ph.D., P.G. (Deceased) Jeffrey D. King, P.G. Thomas A. Sutton, Ph.D., P.G. William S. Hitchcock, Ph.D., LeRoy Jacobs, Ph.D., Charles Weisenberg, Ph.D., and M. David Campbell, P.G. Sponsored by: M. D. Campbell and Associates Houston, Texas The following interim reports contains photographs, figures and tables, which summarize the results to date of long-term investigations on the characteristics and probable impact of naturally-occurring rare earth and uranium and thorium mineralization on the local hydrochemical regime, especially in the shallow ground water of the Seward Peninsula of Alaska. The foundation for this project was completed in 1979 by Michael D. Campbell and a team of field geologists and support staff. The work was summarized in a report cited at the bottom of this web page. Subsequent work was completed in 1984, 1989, and 1997 by a second team of hydrogeologists and geochemists. The initial thrust of the early studies focused on characterizing the geologic framework in the area and on the significant mineralization occurring at the site. Because of the high concentration of the numerous rare-earth minerals, the focus of the investigation was shifted to evaluating the potential impact of the mineralization on the local hydrochemistry and probable hydrogeological behavior of the elements in the ground-water system in the area. None of the work has been published to date, but this interim report serves as a vehicle for eventual publication in one of the appropriate technical journals. Please note that each figure, map or table is a large graphics file and may require some time to download unless a highspeed modem is used. Although inconvenient for slow modems, this is to ensure that the graphics are clear and can be viewed with ease. This is a work in progress. Any comments, remarks or suggestions should be directed to the senior author at: ela1@ela-iet.com. For a PDF file, click (here). Some of the more interesting information on this project has been presented below:

Initial Plan of Operations for the Kachauik Project in 1978.

2 Initial Plan of Operations for the Kachauik Project in Phase I Field Team, Seward Peninsula Project, 1978 Phase I Field Team, 1978: (L to R):

Dr. Charles Weisenberg, Senior Geologist, Herb Nelson, Field Geologist, Steve Campbell, VP Operations, Chang Lee Fung, Field Assistant, Ron Carver, Helicopter Pilot, at Field Base Camp #3.

---------- Phase II Field Team, Seward Peninsula Project, 1978 Phase II Field Team, 1978: (l to R): Steve Campbell, VP Operations, Herb Nelson, Field Geologist, Dr.

3 Dr. Charles Weisenberg, Senior Geologist, Herb Nelson, Field Geologist, Steve Campbell, VP Operations, Chang Lee Fung, Field Assistant, Ron Carver, Helicopter Pilot, at Field Base Camp #3. Photo Taken by Michael D. Campbell, P.G., Chief Geologist Phase II Field Team, Seward Peninsula Project, 1978 Phase II Field Team, 1978: (l to R): Steve Campbell, VP Operations, Herb Nelson, Field Geologist, Dr. Charles Weisenberg, Senior Geologist, Dr. Kevin Biddle, Senior Geologist, Ron Carver, Helicopter Pilot, (Kneeling l to r) Local Field Assistants: Tom George, Jack Batson, Bill Johnson, and Dan Carver, and Dr. Charles Wielchowsky, Senior Geologist. Photo Taken by Michael D. Campbell, P.G., Chief Geologist Outcrop Occurrence of Allanite Mineralization at Sample Location C2-1.

4 Outcrop View of Hornblende Biotite Granodiorite (Location D2-44: Sample D2-53) Intruded by Phonolite Dike (?Pulaskite) (Sample D2-52). Map View of Radiometric Surveys of C2-Series Hill Area: S-N & W-E Lines (see below). West to East Radiometric Ground Survey

5 South to North Radiometric Ground Survey Minerals Tentatively Identified via Petrographic Analysis with Geochemical Anomalies. mm CaO : Na2O + K2O : MgO mmmalkalinity Ratio vs. SiO2

Thin-Section Map of Sample C2-1-1, in Black & White showing large, stubby, euhedral to subhedral

Also showing large, perthitic microcline K- feldspar (white to gray).

6 Solidification Index vs. CaO, Na2O+K20, Fe203, & Alkali - Lime Index Outcrop Sample (C2-1) of Allanite -Bearing Rock. Thin-Section Map of Sample C2-1-1, in Black & White showing large, stubby, euhedral to subhedral crystals of Allanite (black-?vesuvianite). Also showing large, perthitic microcline K- feldspar (white to gray). Plagioclase interstitial to Allanite. Note fractures within Allanite crystals filled with white mineral and occurrence of zoning of the large Allanite crystals. Also note path of Traverse 2, an elemental scan across the field for Uranium and Titanium, shown below. Scale line = 5 mm.

Elemental Scan (Traverse 2) Across Section for Uranium and Titanium.

Light blue areas are Feldspar, white-yellow areas are Zircons, some forms are

). Inclusions thought to be Rare-Earth, Thorium & Uranium minerals at

of Allanite (dark brown- with alteration rim of unidentified yellow-brown,

7 Elemental Scan (Traverse 2) Across Section for Uranium and Titanium. mmm mmmmmmmmmmmmm Cathodoluminescence Photomicrograph Sample C2-17. Approx. 85X. Light blue areas are Feldspar, white-yellow areas are Zircons, some forms are with zoning. Black areas with spherical, muti-colored inclusions are Allanite (?). Inclusions thought to be Rare-Earth, Thorium & Uranium minerals at nucleating sites. Crossed Nicols View of Section of Sample # C2-1C-1. of Allanite (dark brown- with alteration rim of unidentified yellow-brown, isotropic mineral. Small crystalline Plagioclase is white, ground mass, with Apatite imbedded (Ap). mmmmmmmmmmmmm

Crossed Nicols View of Section of Sample # C2-1- 1.

$Note zoning in upper right fractures in Allanite mass filled w/ a highly birefringent white mineral.$ See Thin-Section Map for Location (as Photomicrograph 3).

See Thin-Section Map for Location (as Photomicrograph 3).

grains. Large crystals of K-spar (white to gray). See scale in upper left of photomicrograph.

8 Crossed Nicols View of Section of Sample # C Of Allanite (dark brown) with alteration rim of unidentified yellow-brown, isotropic mineral. Plagioclase is white. See Thin-Section Map for Location (as Photomicrograph 2). Crossed Nicols View of Section of Sample # C Of Allanite (dark brown) with alteration rim of unidentified yellow-brown, isotropic mineral. Plagioclase is white. Note zoning in upper right fractures in Allanite mass filled w/ a highly birefringent white mineral. See Thin-Section Map for Location (as Photomicrograph 3). Thin-Section Map of Sample C2-1C-1, Allanite (black) shown as small- to medium-sized euhedral to anhedral grains. Large crystals of K-spar (white to gray). See scale in upper left of photomicrograph. Scanning Electron Microscope Image (275X) Sample C2-1C (at Location 2) within Traverse 1. mmmmmmmmm

9 mmthorium X-Ray at: 275XmmmmmmmmmmmmmUranium X-ray at: 275X Scanning Electron Microscope Image (275X) Sample C2-1C (at Location 2) within Traverse 1. Elemental Scan (Traverse 1)

10 This interim report is from a report cited as follows: Campbell, M.D., et al., 1979, "Phase II Investigations for Omega Energy and Minerals Corporation, Exploration Activities, Kachauik Peninsula, Alaska," by United Resources International, International Alternate Energy and Geological Consultants, Houston, Texas, December 31, 388 p. Back to M. D. Campbell and Associates Homepage Other In-Progress Field Projects by M. D. Campbell and Associates, Utah project and Arkansas-Oklahoma project.

GY-343 Petrology Petrographic Microscope Laboratory

GY-343 Petrology Petrographic Microscope Laboratory Introduction to the Petrographic Microscope In this laboratory you will be using the petrographic microscope to analyze thin sections of various types of igneous rocks. You will be assigned a thin section