The distribution of bromine in some halite rock salts of the Wieliczka salt deposit (Poland)

R O C Z N I K P O L S K I E G O T O W A R Z Y S T W A G E O L O G I C Z N E G O

V. 51—3/4: 353—359 K ra k ó w 1981

Aleksander

Janusz

THE DISTRIBUTION OF BROMINE IN SOME HALITE ROCK SALTS OF THE WIELICZKA SALT DEPOSIT

(POLAND)

(2 Figs.)

Brom w solach kamiennych złoża solnego Wieliczki

(2 fig.)

Aleksander G a r l i c k i , Janusz W i e w i ó r k a ; The distribution of bromine in some haliite rook salts o f the Wieliczka sa lt deposit (Poland). Ann. Soc. Geol. Po- loniae 51—3/4: 353—359, 1981. Kraków.

A b s t r a c t : Miocene salt deposits in the Carpathian foreland area of Poland have been for the first time a subject of a study of bromine. Bromine content 20—221 ppm, are w ithin the range of salt of marine origin and do not indicate any re-solution. In general, the bromine profiles are norm ally regular or commonly irregular ones. On the ground of distribution of bromine in the Wieliczka profile, three major cycles of salt deposition can be distinguished.

K e y w o r d s : bromine in salt of Wieliczka, Carpathian foreland, Miocene.

Aleksander G a r l i c k i : A cadem y of Mining and Metallurgy, Institute of Geology and Mineral Deposits, al. M ickiewicza 30, 30-059 Kraków, Poland.

Janusz W i e w i ó r k a : Salt Mine Wieliczka, Park Kingi 1, 32-020 Wieliczka, Poland.

manuscript received: June 1980 accepted: August 1980

T r e ś ć : Zawartość bromu w mioceńskich osadach solnych W ieliczki w ynosi 20—221 ppm i potwierdza ich morskie pochodzenie. Autorzy w yróżniają 3 cykle sedym entacyjne na podstaw ie rozkładu zawartości bromu w profilu pionow ym tych osadów.

2 — R o c z n ik P T G 51/3—4

INTRODUCTION

D i s t r i b u t i o n o f b r o m i n e in t h e c h l o r i d e f a e i e s o f m a r i n e e v a p o r i t e s h a s b e e n a s u b j e c t o f a s t u d y o f m a n y w o r k e r s a l l o v e r t h e w o r ld ( B a a r 1 9 6 3 , B o e k e 1908, B r a i t s c h a n d H e r m a n n 1 96 2 , 1 9 6 3 , d ’A n s a n d K i ih n 1 9 4 0 , H i t e 1 9 7 0 , 1 9 7 4 , H o l s e r 1 9 6 6 , K u h n 1 9 5 5 a , b, 1 96 8 , R a u p 19-66, S c h u l t z e 1 9 6 0 , S c h w e r d t n e r a n d W a r d l a w 1 9 6 3 , V a l y a s h k o 1 9 5 6 , Z a k 1 9 6 9 , 1 9 7 4 , a n d o t h e r s . T h e s e s t u d i e s h a v e p r o v i d e d a n im p o r t a n t g e o ­ c h e m i c a l t o o l in r e s o l v i n g o f s t r a t i g r a p h i c p r o b l e m s a n d in p r o s p e c t i n g f o r p o t a s h d e p o s i t s .

In t h e t e r r i t o r y o f P o l a n d , t h e f i r s t c o m p r e h e n s i v e s t u d y o f b r o ­ m i n e d i s t r i b u t i o n w a s c a r r ie d b y C h a r y s z (1 9 7 3 ). T h e w o r k d e a l s m a i n l y w i t h t h e Y o u n g e r S a l t s o f t h e Z e c h s t e i n Z 3 s t a g e , b u t t h e s t u d i e s h a v e b e e n e x t e n d e d to t h e u n d e r l y i n g a n d o v e r l y i n g r o c k u n i t s (Z 2 a n d Z 4 s t a g e s ) .

W i t h i n t h e M i o c e n e s a l t d e p o s i t s in t h e C a r p a t h i a n f o r e l a n d a r e a o f P o l a n d , b r o m in e g e o c h e m i s t r y h a s n o t b e e n c a r r ie d o u t s o f a r . T h e p r e ­ s e n t p a p e r is t h e f i r s t a t t e m p t t o r e l a t e t h e b r o m in e d a t a t o t h e p a l e o s a - l i n i t i e s o f t h e B a d e n i a n r o c k s a l t b e d s a t t h e W i e l i c z k a s a l t d e p o s it .

STRATIGRAPHY AND PETROLOGY

T h e s a l t d e p o s i t a t W ie l i c z k a s i t u a t e d 13 k m . s o u t h o f K r a k o w , is 1 k m . w i d e , a b o u t 10 k m . l o n g , o v e r 4 0 0 m . d e e p , a n d c o n s is t s o f t w o e s s e n t i a l p a r t s . T h e u p p e r o n e is d e v e l o p e d in t h e f o r m o f c o a r s e b r e c c ia c o m p o s e d m a i n l y o f s a l t y c l a y s ( „ z u b e r ” ), w i t h b lo c k s o f c o a r s e - g r a i n e d s a l t , c a l l e d g r e e n s a l t . T h e s e b lo c k s o f ir r e g u l a r s h a p e a n d v a r i o u s t h i c ­ k n e s s in s o m e p l a c e s r e a c h a n e x t e n s i o n o f m o r e t h a n 150 m e t r e s . T h is p a r t is s u p p o s e d t o b e t h e f a e i e s e q u i v a l e n t o f t h e l o w e r o n e . T h e l o w e r p a r t o f t h e d e p o s i t is d e v e l o p e d a s a c o m p l e x o f s a l t l a y e r s s t r o n g l y f o ld e d , d e f o r m e d , a n d t h r u s t o v e r o n e a n o t h e r , c a l l e d „ s t r a t i f i e d ” o r

„ b e d d e d ” p a r t o f t h e d e p o s i t . F r o m t h e s o u t h , f l y s c h s e d i m e n t s in t h e f o r m o f t o n g u e - s h a p e d w e d g e s a r e s q u e e z e d i n t o t h e in n e r p a r t o f t h e s a l t d e p o s i t .

R e c o n s t r u c t e d n o r m a l s t r a t i g r a p h i c p r o f i l e ( F ig . 1) o f t h e b e d d e d p a r t o f t h e d e p o s i t is a s f o l l o w s ( f r o m t h e b o t t o m ) :

— a n h y d r i t i c c l a y s t o n e s a n d s i l t s t o n e s ,

— t h e o l d e s t s a l t s ( v a r ig r a in e d s a l t s w i t h a d m i x t u r e a n d i n t e r c a l a ­ t i o n s o f c l a y , s i l t , a n d s a n d ) ,

— s a l t y s a n d s t o n e s a n d s i l t s t o n e s , p a r t l y c o n g l o m e r a t i c ,

— s e t o f g r e e n l a y e r e d s a l t s ( n u m b e r e d I— V ) , i n t e r c a l a t e d w i t h a n - h y d r i t i c c l a y s t o n e s ,

— s h a f t s a l t ( c o a r s e - g r a i n e d s a l t d e v o i d o f m i n e r a l a d m i x t u r e s b u t w i t h t r a c e s o f g a s e o u s h y d r o c a r b o n s ) ,

— l o w e r s p i z a s a lt s

— c e n t r a l i n t e r c a l a t i o n ( a n h y d r it ic c l a y s t o n e ) ,

— u p p e r s p i z a s a l t s ( b o t h l o w e r a n d u p p e r s p i z a s a l t s a r e c o a r s e ­ g r a i n e d , b a n d e d , w i t h i n t e r c a l a t i o n s o f s a n d y a n h y d r i t i c c l a y s ) ,

— c l a y s t o n e s , s i l t s t o n e s , a n d s a n d s t o n e s , a n h y d r i t i c in t h e u p p e r p a r t .

r 70

h 60

WT2- 1”».... 6

Fig. 1. Schematic columnar section of the W ieliczka salt deposit 1 — m arly clay­

stones (Skawina beds), 2 — salty sandstones and siltstones, 3 — anhydritic clay­

stones and siltstones, 4 — rock salt, 5 — claystones and siltstones (Chodenice beds), 6 — distingiuished tu ffite intercalations. N — oldest salts, ZP — set of green layered salts, numbered I—V, SZ — shaft salt, SD — low er spiza salts, SG —

upper spiza salts

Fig. 1. Schem atyczny profil litologiczny złoża solnego W ieliczki 1 — iłow ce mar- gliste (warstwy skawińskie), 2 — piaskowce i m ułow ce solne, 3 — iłow ce i mułowce anhydrytowe, 4 — sól kamienna, 5 — iłow ce i m ułow ce (w arstw y chodenickie), 6 — wyróżnione w kładki tufitow e. N — sole najstarsze, ZP — zespół zielonych soli pokładowych, num ery pokładów I—V, SZ — sól szybikowa, SD — sole spiżowe

dolne, SG — sole spiżowe górne

2*

T h e p r i m a r y t h i c k n e s s o f t h i s s e q u e n c e w a s ca . 7 0 m . A t t h e b o t t o m o f e v a p o r i t e s a n d w i t h i n t h e l o w e r p a r t o f t h e g r e e n l a y e r e d s a lt s , t h r e e t h i n t u f f i t e i n t e r c a l a t i o n s h a v e b e e n d i s t i n g u i s h e d , b e i n g t h e i m ­ p o r t a n t m a r k e r b e d s .

METHODS OF SAMPLING AND ANA LY SIS

S a m p l e s o f h a l i t e w e r e c o l l e c t e d a t 0 .2 — 0 .5 m i n t e r v a l s t h r o u g h t h e t o t a l t h i c k n e s s o f e a c h s a l t b e d . W i t h i n t h e u p p e r s p iz a s a l t s t h e s p a c i n g v a r i e d f r o m 0 .5 — 1.0 m , d e p e n d i n g o n t h e u n i f o r m i t y o f s a l t a n d t h e p o s i t i o n o f n o n - h a l i t e in t e r c a l a t i o n s . F r o m t h e w a l l s o f t h e m i n e - g a l l e - r i e s t h e m a t e r i a l w a s h a n d p i c k e d t o g e t t h e p u r e s t s a m p l e o f h a l i t e p o s s i b l e f r o m e a c h i n t e r v a l . T h e t o t a l a m o u n t o f c o l l e c t e d s a m p l e s w a s

— 1 0 2.

A l l s a m p l e s w e r e a n a l y z e d in t h e L a b o r a t o r y o f t h e G e o lo g ic a l I n ­ s t i t u t e , W a r s a w , u s i n g c o l o u r i m e t r i c p r o c e d u r e . A s a c h e c k o n t h e a c ­ c u r a c y o f t h e a p p l i e d m e t h o d , 2 0 s a m p l e s w e r e a ls o a n a l y z e d t w i c e a n d t h e r e s u l t s w e r e s u b s t a n t i a l l y i n a g r e e m e n t w i t h t h o s e p r e v i o u s .

BROMINE PROFILES

T h e v a r i a t i o n o f b r o m in e c o n t e n t a n d o f b r o m i n e - c h l o r i n e r a t io in r e l a t i o n to t h e t h i c k n e s s o f e a c h s a l t b e d a r e p l o t t e d in F ig . 2.

W i t h i n t h e l o w e r m o s t p a r t o f t h e p r o f i l e c o r r e s p o n d in g t o t h e o l d e s t s a l t s , t h e b r o m in e c o n t e n t a t t h e b a s e is 18 p p m a n d in c r e a s e s u p w a r d t o 4 0 p p m . T h e u p p e r m o s t t w o m e t r e s o f t h e o l d e s t s a l t s d i s p l a y b r o ­ m i n e v a l u e s w i t h i n t h e r a n g e o f 4 0 — 5 0 p p m . T h e l a s t s a m p l e t a k e n

f r o m t h e v e r y t o p o f t h e o l d e s t s a l t s s h o w s a r a p id in c r e a s e o f b r o m in e c o n t e n t , u p t o 221 p p m . G e n e r a l f e a t u r e o f t h e p r o f i l e u n d e r d i s c u s s i o n is g r a d u a l i n c r e a s e in s a l i n i t y . T h e r a p id in c r e a s e in s a l i n i t y in t h e u p ­ p e r m o s t p a r t o f t h e p r o f i l e s h o w s r e s t r i c t e d c o n d it io n s o f s e a w a t e r , w h i c h m a y b e s u f f i c i e n t f o r p r e c i p i t a t i o n o f p o t a s s i u m m i n e r a l s . T h e s e c o n d i t i o n s w e r e c h a n g e d a b r u p t l y by' t h e i n f l o w o f c o n s id e r a b le a m o u n t o f t e r r e s t r i a l m a t e r i a l d e p o s i t e d in t h e f o r m o f c o n g l o m e r a t i c s a l t y s a n d ­ s t o n e s a n d s i l t s t o n e s , o v e r l y i n g t h e o ld e s t s a lt s . T h is p r o f i l e m a y b e c o n ­ s id e r e d a s n o r m a l l y r e g u l a r p r o f i l e d i s t i n g u i s h e d b y H o l s e r (1 9 6 6 ) a n d r e s e m b l e s t h o s e p r e s e n t e d b y S c h u l t z e (1 9 6 0 ) f o r t h e Z e c h s t e i n s e r i e s , a n d b y R a u p (1 9 6 6 ) f o r s a l t b e d 3 in P a r a d o x M e m b e r .

G r e e n l a y e r e d s a l t s d i s p l a y f a i r l y u n i f o r m b r o m in e c o n t e n t , w i t h i n t h e r a n g e 2 4 — 48 p p m . T h e p r o f i l e o f s a l t b e d I V s h o w s a n in c r e a s e o f t h e b r o m i n e c o n t e n t f r o m t h e b o t t o m t o t h e to p . In t h e p r o f i l e o f s a l t b e d III, a f t e r i n i t i a l d e c r e a s e o f t h e b r o m i n e c o n t e n t , t h e u p p e r p a r t o f t h e p r o f i l e is a l m o s t s m o o t h . S a l t b e d II p r o f i l e s h o w s s l i g h t in c r e a s e o f

m

B r ppm

i --- 1--- 1 U 10 n

20 (0 80 80 ar ppm

i ... .

002 006 0.1 0.U

«0

Br pęm

r rri f " T " ! 006 ai ou oa

B r- P 3

ci Fig. 2. Bromine profiles of salt beds, W ieliczka salt deposit

Fig. 2. Profile bromowe w arstw soli w złożu solnym Wieliczki

Br ppm I I I I

20 40 60 80

{

i

i

■>

/

rrrl'l Cl

002 006 0.1 o .u

B r - C '

f11 ■ i ■1 ■

i ■ •' i

Q06ai co4 os

b r o m in e c o n t e n t i n t h e m i d d l e o f t h e b e d . I n t h e p r o f i l e o f s a l t b e d I t h e r e a r e v e r y s m a l l i r r e g u l a r i t i e s in b r o m in e c o n t e n t , h o w e v e r t h e b r o m i n e - c h l o r i n e r a t io s h o w s a n d i n c r e a s i n g v a l u e i n t h e u p p e r p a r t o f t h e p r o f i l e . B r o m i n e c o n t e n t i n t h e l a s t s a m p l e o f e a c h g r e e n s a lt b e d s h o w s s i m i l a r v a l u e t o t h a t t a k e n f r o m t h e b o t t o m o f t h e y o u n g e r b e d . T h is m a y s u g g e s t t h e c o n t i n u i t y o f t h e b r o m i n e p r o f i l e a n d t h e r e ­ f o r e c o n tin o 'u s s a l i n i t y c h a n g e s i n t h e b a s in , d e s p i t e t h o s e i n t e r r u p t i n g e p i s o d e s d u r i n g w h i c h i n t e r c a l a t i o n s o f a n h y d r i t i c c l a y s t o n e s w e r e d e p o -

s i t e d . B r o m i n e p r o f i l e o f t h e g r e e n l a y e r e d s a l t s , c o n s id e r e d a s a w h o l e , d i s p l a y s s o m e f e a t u r e s o f r e g u l a r o n e .

W i t h i n t h e n e x t p a r o f t h e p r o f i l e b e i n g p l o t t e d f o r t h e s h a f t s a l t , t h e b r o m i n e c o n t e n t in c r e a s e s f r o m 22 p p m to 46 p p m , a n d t h e n g r a ­ d u a l l y d e c r e a s e s t o 30 p p m . T h e l a s t p a r t o f t h i s p r o f i l e s h o w s v a l u e s a b o u t 40 p p m .

S e d i m e n t a t i o n o f t h e l o w e r s p iz a s a l t s s t a r t e d f r o m m o r e c o n c e n t r a ­ t e d b r in e , w h a t is i n d ic a t e d b y t h e r is e o f b r o m in e c o n t e n t f r o m 59 p p m t o 67 p p m . S u b s e q u e n t l y g r a d u a l d e c r e a s e o f b r o m in e c o n t e n t d o w n to 2 6 p p m t a k e s p l a c e , c a u s e d b y b r i n e d i l u t i o n t h a t p r o b a b l y r e s u l t e d f r o m t h e i n f l u x o f s e a w a t e r i n t o t h e b a s in . A f t e r t h a t p e r i o d o f d i l u t i o n , t h e f i n a l p a r t o f t h e p r o f i l e s h o w s s t e a d y in c r e a s e o f b r o m in e u p t o 63 p p m .

B r o m i n e p r o f i l e o f t h e s h a f t s a l t a s w e l l a s t h a t o f t h e l o w e r s p iz a s a l t s m a y b e c o n s i d e r e d a s c o m m o n l y ir r e g u l a r p r o f i l e s . H o w e v e r , t h e s a l i n i t y o f b r i n e g e n e r a l l y in c r e a s e d f r o m t h e b o t t o m o f t h e s h a f t s a lt to t h e to p o f t h e l o w e r s p iz a s a l t s , y e t s o m e c h a n g e s in s l o p e o f t h e p r o f i l e , i n d i c a t i n g a n in c r e a s e a n d d e c r e a s e o f b r o m in e in h a l i t e , m a y r e f l e c t f e w m a j o r p e r i o d s d u r i n g w h i c h t h e i n c r e a s e in s a l i n i t y w a s i n ­ t e r r u p t e d b y b r in e d i l u t i o n .

T h e l a s t b r o m in e p r o f i l e c o r r e s p o n d i n g t o t h e u p p e r s p iz a s a lt s , s h o w s g e n e r a l l y in c r e a s i n g b r o m in e c o n t e n t f r o m 3 0 p p m t o 80 p p m . T h is is n o r m a l l y r e g u l a r p r o f i l e . H o w e v e r , t h e u p p e r m o s t p a r t o f t h e u p p e r s p iz a s a l t s c o u l d n o t b e s a m p l e d d u e t o i n t e n s e t e c t o n i c d i s t u r ­ b a n c e s . T h e r e f o r e , t h e r e a r e i n s u f f i c i e n t d a t a f r o m t h i s s e c t i o n .

CONCLUSIONS

B r o m i n e c o n t e n t in t h e p r o f i l e o f t h e W i e l i c z k a s a l t d e p o s i t , 2 0 — 221 p p m , is w i t h i n t h e r a n g e o f s a l t o f m a r i n e o r i g in .

G e n e r a l l y , t h e b r o m i n e p r o f i l e s a r e n o r m a l l y r e g u l a r o r c o m m o n l y i r r e g u la r o n e s . B r o m i n e - c h l o r i n e r a t io c u r v e s a r e v e r y s i m i l a r t o t h o s e p l o t t e d f o r t h e b r o m in e c o n t e n t .

O n t h e b a s is o f d i s t r i b u t i o n o f b r o m i n e t h r e e m a j o r s e d i m e n t a r y c y ­ c l e s c a n b e d i s t i n g u i s h e d , n a m e l y : 1. t h e o l d e s t s a l t s , 2. g r e e n l a y e r e d s a l t s , s h a f t s a l t , a n d t h e l o w e r s p iz a s a l t s , 3. t h e u p p e r s p i z a s a l t s .

F i n a l s t a g e o f t h e o l d e s t s a lt s s e d i m e n t a t i o n w a s t h e p e r i o d o f t h e m o s t r e s t r i c t e d c o n d i t i o n s i n t h e b a s in , e x p r e s s e d b y t h e h i g h e s t b r o ­ m i n e c o n t e n t , b u t t h e i n f l o w o f f r e s h w a t e r w i t h t e r r e s t r i a l m a t e r i a l a b r u p t l y c h a n g e d t h e s e c o n d i t i o n s a n d m a d e i m p o s s i b l e p r e c i p i t a t i o n o f p o t a s s i u m m i n e r a l s .

REFERENCES — WYKAZ LITERATURY

B a a r C. A. (1963), Der Brom gehalt ais stratigraphischer Indikator in Steinsalz- lagerstatten.

Neues Jb. Miner.

B o e k e H. E. (1908), Uber das Kristallisationsschem a der Chloride, Bromide, Jodide von Natrium, Kalium und Magnesium, sow ie iiber das Vorkommen des Broms und das Fehlen von Jod in den Kalisalzlagerstatten. Z.

Kristallogr.,

391.

B r a i t s c h O., H e r r m a n n A. G. (1962), Zur Brom verteilung in salinaren Salz- system en bei 25°C.

Naturw.,

B r a i t s c h O., H e r r m a n n A. G. (1963), Zur G eochem ie des Broms in salinaren Sedimenten. Teil I.

Geochim. et Cosmochim. Acta,

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STRESZCZENIE

B a d a n ia z a w a r t o ś c i b r o m u w s o l a c h 'k a m ie n n y c h b y ł y p r z e d m i o t e m l i c z n y c h p r a c g e o l o g i c z n y c h n a ś w i e c i e . S z c z e g ó l n e z n a c z e n i e t y c h p r a c p o l e g a n a ic h p r z y d a t n o ś c i w r o z w i ą z y w a n i u p r o b l e m ó w s t r a t y g r a f i c z ­ n y c h o s a d ó w s o l n y c h o r a z w p o s z u k i w a n i u s o l i p o t a s o w o - m a g n e z o w y c h . N a o b s z a r z e P o l s k i b a d a n ia t a k i e p r o w a d z o n o d o t y c h c z a s w o s a d a c h c e c h s z t y n u , a n i n i e j s z a p r a c a j e s t p i e r w s z ą p r ó b ą o k r e ś l e n i a z a w a r t o ś c i b r o m u w m i o c e ń s k i c h o s a d a c h s o l n y c h . B a d a n ia m i o b j ę t o p r o f i l d o l n e j , u w a r s t w i o n e j c z ę ś c i z ł o ż a s o l n e g o W i e lic z k i , j a k o n a j l e p i e j p o z n a n y i u m o ż l i w i a j ą c y r e k o n s t r u k c j ę p i e r w o t n e g o n a s t ę p s t w a i m i ą ż s z o ś c i w a r s t w (fig . 1).

P r ó b k i s o l i b y ł y p o b i e r a n e w o d s t ę p a c h 0 ,2 — 0,5 m z k a ż d e j w y d z i e ­ lo n e j w a r s t w y . W s o l a c h s p i ż o w y c h g ó r n y c h p r ó b k i p o b ie r a n o w o d s t ę ­ p a c h 0 ,5 — 1,0 m , w z a l e ż n o ś c i od j e d n o r o d n o ś c i w y k s z t a ł c e n i a s o l i i p o ­ z y c j i w k ł a d e k i l a s t o - a n h y d r y t o w y c h . O g ó ł e m w p r o f i l u z ł o ż a p o b r a n o 102 p r ó b k i, k t ó r e b y ł y a n a l i z o w a n e w G ł ó w n y m L a b o r a t o r i u m I n s t y t u ­ t u G e o l o g i c z n e g o w W a r s z a w ie .

Z a w a r t o ś c i b r o m u w p r ó b k a c h o r a z w y l i c z o n e w a r t o ś c i w s p ó ł c z y n n i ­ k a b r o m o c h l o r o w e g o p r z e d s t a w i o n o g r a f i c z n i e n a f ig . 2. W s o l a c h n a j ­ s t a r s z y c h z a w a r t o ś ć b r o m u w z r a s t a o d 18 p p m d o 50 p p m , a p r z y s t r o ­ p ie d o c h o d z i n a w e t d o 221 p p m . W s o l a c h z i e l o n y c h p o k ł a d o w y c h z a w a r ­ t o ś ć b r o m u m i e ś c i s i ę w g r a n ic a c h 2 4 — 48 p p m . W s o l i s z y b i k o w e j z a ­ w a r t o ś ć b r o m u p o c z ą t k o w o w z r a s t a od 2 2 p p m d o 46 p p m , a n a s t ę p n i e u t r z y m u j e s i ę w g r a n ic a c h 3 0 — 40 p p m . S e d y m e n t a c j a s o l i s p i ż o w y c h d o l n y c h r o z p o c z ę ła s i ę z b a r d z ie j s k o n c e n t r o w a n y c h r o z t w o r ó w , n a c o w s k a z u j e z a w a r t o ś ć b r o m u w z r a s t a j ą c a o d 59 p p m d o 67 p p m . W d a l ­ s z e j c z ę ś c i p r o f i l u z a w a r t o ś ć t a m a l e j e d o 26 p p m i p o n o w n i e w z r a s t a d o 63 p p m . Z a w a r t o ś ć b r o m u w s o l a c h s p i ż o w y c h g ó r n y c h s t o p n i o w o w z r a s t a od 30 p p m d o 8 0 p p m .

Z a w a r t o ś ć b r o m u w s k a ł a c h s o l n y c h W ie l i c z k i , m i e s z c z ą c a s i ę w p r z e ­ d z i a l e 2 0 — 2 2 1 p p m , w s k a z u j e n a ic h m o r s k i e p o c h o d z e n i e . P r o f i l e b r o ­ m o w e t y c h s o l i m o ż n a z a l i c z y ć d o r e g u l a r n y c h lu b p o s p o l i c i e w y s t ę p u ­ j ą c y c h n i e r e g u l a r n y c h . R o z k ła d z a w a r t o ś c i b r o m u w p r o f i l u p i o n o w y m o s a d ó w s o l n y c h z ło ż a W i e l i c z k i p o z w a l a n a w y d z i e l e n i e 3 g ł ó w n y c h c y ­ k l i s e d y m e n t a c y j n y c h , o b e j m u j ą c y c h : 1. s o l e n a j s t a r s z e , 2. z i e l o n e s o l e p o k ł a d o w e , s ó l s z y b i k o w ą i s o l e s p i ż o w e d o l n e , 3. s o l e s p i ż o w e g ó r n e .

K o ń c o w e s t a d i u m s e d y m e n t a c j i s o l i n a j s t a r s z y c h b y ł o o k r e s e m n a j ­ b a r d z ie j o g r a n ic z o n e j c y r k u l a c j i w ó d w b a s e n ie , c z e g o d o w o d e m j e s t n a j w y ż s z a z a w a r t o ś ć b r o m u , j e d n a k n a p ł y w s ł o d k i c h w ó d n i o s ą c y c h m a ­ t e r i a ł z lą d u g w a ł t o w n i e z m i e n i ł t e w a r u n k i i u n i e m o ż l i w i ł o s a d z a n ie s i ę m i n e r a ł ó w p o t a s o w o - m a g n e z o w y c h .