Moiin]  THE    KOTZEBUE    PLACER    GOLD    FIELD,    ALASKA.  75 
Three  principal  streams  flow  through  the  district — the  Inmachuk, 
Kugruk,  and  Kiwalik  rivers.  All  these  have  a  general  northerly 
course  and  drain  an  area  of  between  1,500  and  2,000  square  miles.  Of 
the  three  the  Kugruk  is  the  largest  and  economically  the  least  impor- 
tant, since  very  little  gold  has  been  taken  from  it.  Kiwalik  River, 
the  second  in  size,  is  of  special  interest  because  its  tributary,  Candle 
Creek,  has  produced  more  than  three  times  as  much  as  the  combined 
output  of  the  other  creeks.  The  Inmachuk  and  two  of  its  tributaries, 
Old  Glory  and  Hannum  creeks,  have  afforded  much  the  larger  part  of 
the  remainder.  Besides  these  Bear  Creek,  which  empties  into  Buck- 
land  River,  and  the  Alder  Creek  beach  diggings  should  be  mentioned, 
as  well  as  Chicago  Creek,  a  tributary  of  the  Kugruk,  on  which  a  coal 
or  lignite  bed  was  worked  during  the  past  winter. 
The  topography  of  the  country  south  of  Kotzebuc  Sound  is  gener- 
ally of  low  relief  and  monotonous  appearance.  Here  and  there,  as  in 
the  vicinity  of  the  Asses  Ears,  a  prominent  elevation  south  of  Good 
Hope  Bay,  so  named  by  Kotzebue  in  1816  because  "its  summit  is  in 
the  form  of  two  asses  ears,"  and  on  the  divide  between  Kiwalik  and 
Buckland  rivers,  more  elevated  masses  of  limestone  or  eruptive  rocks 
reach  a  height  of  from  1,500  to  2,500  feet  above  sea  level. 
The  field  may  be  reached  from  Nome  either  by  overland  trail  or  by 
boat  through  Bering  Strait  and  Kotzebue  Sound,  the  distance  in  the 
first  case  being  over  150  miles  directly  across  the  peninsula,  and  in  the 
second  case  about  300  miles.  Of  the  two  the  water  route  is  now  gen- 
erally preferred,  but  can  be  used  only  fof*  about  three  months  in  the 
year,  since  navigation  is  closed  by  the  ice  during  the  remaining  nine 
months. 
GEOLOGIC    SKETCH. 
The  rocks  of  the  Kotzebue  gold  field  are  almost  entirely  micaceous 
and  graphitic  schists  of  uncertain  age  and  thickness,  interstratified  with 
occasional  beds  of  limestone  and  overlain  by  an  extensive  flow  of  recent 
cellular  lavas. 
The  highly  metamorphosed  rocks  must  have  suffered  an  immense 
amount  of  erosion  and  were  reduced  to  an  almost  level  plain  with  here 
and  there  low  hills  of  limestone  and  sometimes  of  granite  rising  above 
it.  Over  much  of  this  plain  was  then  poured  out  a  thin  sheet  of  lava, 
which  overflowed  several  thousand  square  miles  of  territory,  filling 
up  the  depressions  and  surrounding  the  higher  points.  On  account  of 
the  lava  and  overlying  tundra,  outcrops  of  the  schist  are  not  plentiful 
md  are  generally  found  where  the  streams  have  cut  their  way  through 
the  eruptive  sheet,  forming  canyon-like  valleys  bordered  by  rims  of 
■broken  lava  blocks. 
Both  schists  and   limestones  are  much  folded,  showing  that  they 
liave  been  subjected  to  great  pressure,  and  the  schists  have  been  further 
nodified  by  the  formation  of  a  complicated  series  of  quartz  veins  and 
lenses,  fragments  of  which  form  a  considerable  portion  of  the  grave's. 
