Chap. 5] 



GEOPHYSICAL METHODS IN MINING 



51 



is the application of magnetic methods to the mapping of contact-meta- 

 morphic iron ores. For the location of contact-metamorphic sulfides, elec- 

 trical methods have been employed. Magnetic exploration may be of 



Deposit 



Ttfpe Localitif 

 (6eophifS/ctt/ 

 orSeo/ogkttO 



Geologic Form 



Seopht/s/ctt/ 

 Method 



direct I struct 



III. Auto genetic Solution Deposits 



i^esidua/ iveetkeriHf 8 



S9C.d8fu.:Uaenitt, 



Hematite. 



Menqenese. 



Bauxite 



Vuiedium, Ureitient 55 



Mative fepper deposits 

 formed l>q zeolikiM 

 ttoa of tamts 



/Utaioma 



CuAa 

 ArteonsMS 



Colo. 



laiT Superior 

 (possibly in ff V 



mofo. 

 maqn. 



ma/n.f 

 nadisacf 



mega 

 meqn 



ateqn 



IV Sedimentation Deposits 



I/torfomc: Idinefte, 

 Salt Potesk, Bgpswa 

 Limestone, Cement 

 rocks 



Organic: Coal. 

 Lignite 



Clinton. Lorraine 

 Stessturt, CarlsbaA 



f» nu '/.Hl. f W^\i< r\*\\\ ■'v ' ^U J 



•I II 



T TTT 



resist, 

 seism. 



elect 



magn. 

 resist, 

 seism. 



resist 

 seism. 



V Dt/namo-metamorptiic Deposits 



Magnetite 

 Pyrrttoflte 



Kurslc.Adfrond- 

 ades. MK M.J. 

 Daclcto¥tm 



■'5tif. 



Schtsb 



\qroK 

 elect. 



VI. Mechanical Concentration Deposits 



6okf (also Tin and 

 Ptatinum) Placers 



6old- 

 Cmgtomerates 



JUeske. Bn 

 Col, Cafif.. etc. 



Wifwotersrand 

 (Possibly in 

 6 roup n) 



m^n 

 (bhdc ,, 



elec. 

 seism. 



sets.(V 



Fig. 5-lb. Genetic classification of mineral deposits and applications of geophysical 



methods (concluded). 



assistance for structural investigations (mapping of intrusives, contact 

 zones, and the like). 



Electrical methods have good possibilities in the direct or indirect loca- 

 tion of deposits falling in the category of hot-water concentrations. Ex- 



