GEOLOGICAL SURVEY CIRCULAR 587 

Gold Distribution in 

Surface Sediments on 

the Continental Shelf 

off Southern Oregon: 

A Preliminary Report 
Gold Distribution in 

Surface Sediments on 

the Continental Shelf 

off Southern Oregon: 

A Preliminary Report 

By H. Edward Clifton 

G E 0 L 0 G I C A L S U R V E Y C I R C U L A R 587 

Washington 1968 
United States Department of the Interior 

STEWART L. UDALL, Secretary 

Geological Survey 

William T. Pecora, Director 

,,.(r 

Free on application to the U.S. Geological Survey, Washington, D.C. 20242 
CONTENTS 

)lbstract _____________________________________ _ 

Introduction __________________________________ _ 

]dethods,-------------------------------------

Gold distribution ______ ------------___________ _ 

Page 

1 

1 

1 

4 

Origin and potential economic significance of the 

gold anomalies _________ ------------------- Conclusions __________________________________ _ 

References cited ______________________________ _ 

ILLUSTRATION 

FIGURE 1. Locations of surface grab samples that have been analyzed for gold 

iii 

Page 

5 

5 

5 

Page 

2 
GOLD DISTRIBUTION IN SURFACE SEDIMENTS ON THE CONTINENTAL SHELF 

OFF SOUTHERN OREGON: A PRELIMINARY REPORT 

By H. EDWARD CUIFTON 

Abstract 

Local concentrations of gold have been identified in 

surface sediments on the continental shelf off southern 

Oregon between Cape Arago and Cape Sebastian, a 

distance of about 40 miles. Concentrations of gold range 

from the lower limit of detection, 5 parts per billion, 

to almost 150 parts per billion. The largest gold 

anomaly is an area of 1'5 to 20 square miles off Cape 

Blanco. Gold is associated with black sands believed 

to be relict beach placers formed during a previous low 

stand of the sea. Although the gold content is low, it 

may indicate higher grade material at depth; drilling 

will be necessary to determine the economic potential of 

the placers. 

INTRODUCTION 

The Heavy Metals program of the U.S. 

Geological Survey was initiated in 1966 to 

stimulate domestic production of a small group 

of critical metals (U.S. Geological Survey, 

1968). As part of this program, study of the 

black sands of southern Oregon was begun, the 

goal being to establish the economic potential, 

particularly as regards gold and platinum, for 

black sands on the continental shelf. To implement this study, a joint research contract 

was entered into with the Department of 

Oceanography, Oregon State University, for 

examination of the continental shelf. Concurrent with this examination, a study of the 

black sands in emergent terrace and modern 

beach deposits has been carried on by personnel of the Geological Survey, as well as a 

study of the sources for potential heavy metals 

deposits under a joint research contract with 

the University of Oregon. 

Although this investigation is not yet complete, several preliminary conclusions can be 

drawn concerning the heavy metals potential 

of the southern Oregon continental shelf. 

Kulm, Heinrichs, Buehrig, and Chambers 

1 

(1968) described and interpreted the distribution of heavy minerals and associated magnetic anomalies on the shelf. The present 

report describes the distribution of gold in 

surface sediment on the continental shelf and 

its relation to the associated black sands. 

Many persons have contributed to this 

study. R. L. Phillips has assisted throughout 

the project. The following individuals participated in sample preparation: F. J. Swanson, 

D. A. D'Armond, John Harding, J. M. Kelly, 

R. R. Payne and V. G. Wood. Most analyses 

were made by Arthur Hubert. 

METHODS 

To date 120 surface-sediment samples collected from the continental shelf (fig. 1) have 

been analyzed for gold. Seventy-eight of these 

samples were collected by ,the U.S. Geological 

Survey RV Polaris (under the direction of 

G. A. Rusnak) during the first year of the 

study; knowledge of the gold and heavy mineral content of these samples was ill'strumental 

in planning subsequent sampling on the, shelf. 

The remaining samples were collected by Oregon State University personnel as described by 

Kulm, Heinrichs, Buehrig, and Chambers 

(1968). Analysis for gold in other samples, 

including many from areas previously unsampled, will soon be completed. It is anticipated, 

however, that these analyses will not significantly change the conclusions drawn in this 

report. 

In order to achieve accurate reproducible 

analytical data, all the samples were concentrated prior to analysis, according to the procedures outlined by Clifton, Hubert, and Phillips (1967). Gold content was determined by 
43°~--------~r---~-----+-------+----~---r--~~ EXPLANATION 

oo' ---100---

---75---

Contours, showing gold values 

in parts per billion 

--50--

--40--

Contours, showing depth in fat'homs 

After J . V. By rne 

• Sample location 

U.S. Geological Survey RV Polaris, 

cruise Sept. 1966 ---

A 

Sample location 

RV Yaquina, cruise 6707 July 1967 

Stippling shows areas 

within which samples contain at least 5ppb gold 

20 

FIGURE 1.-Locations of surface grab samples that have been analyzed for gold. Northern area. 

2 
42°~--+---~~~~--~--~~~~~~~--~~~-+-+~ 

201 

NAUTICAL 

0 

I 

I 

0 5 

KILOMETERS 

MTN. 

FIGURE 1.-Locations of surface grab samples that have been analyzed for gold. Southern area. 

3 
•-

research 1965: U.S. Geol. Survey Prof. Paper 525-C, 

p. C168-C171. 

Pard~~- J _ T __ L()34__ .Be.ach nlac_el:s of the Ore ~ron CQast: 

U.S. Geological Survey, 1968, U.S. Geological Survey 

heavy metals program progress report, 1966 and 

19_6_7~ U.S_. Geol.___Eyrve Circ. 5Q_Q_, 24 p,