﻿70 
  SANTA 
  MARTA 
  OIL 
  DISTRICT, 
  CALIFORNIA. 
  

  

  had 
  been 
  more 
  highly 
  tilted 
  the 
  later 
  sediments 
  were 
  laid 
  down 
  

   unconformably. 
  In 
  places 
  (he 
  first 
  Fernando 
  beds 
  were 
  of 
  similar 
  

   lithologic 
  character 
  to 
  the 
  Monterey 
  shale, 
  being 
  deposited 
  probably 
  

   under 
  similar 
  conditions 
  or 
  else 
  derived 
  from 
  the 
  redeposition 
  of 
  the 
  

   shale 
  material. 
  This 
  similarity, 
  added 
  to 
  the 
  bedding 
  conformity, 
  

   caused 
  the 
  formations 
  to 
  appear 
  as 
  completely 
  conformable 
  and 
  con- 
  

   tinuous. 
  But 
  the 
  presence 
  in 
  places 
  of 
  layers 
  of 
  brecciated 
  Monterey 
  

   shale 
  at 
  the 
  base 
  of 
  the 
  Fernando, 
  and 
  in 
  places 
  of 
  true 
  angular 
  

   unconformities, 
  proves 
  that 
  a 
  period 
  of 
  erosion 
  preceded 
  the 
  Fer- 
  

   nando 
  deposition. 
  

  

  After 
  the 
  period 
  of 
  deposition 
  of 
  the 
  finer 
  sediments 
  usually 
  found 
  

   at 
  the 
  base 
  of 
  the 
  Fernando, 
  shallow-water 
  conditions 
  prevailed. 
  

   The 
  deposits 
  were 
  almost 
  entirely 
  detrital, 
  the 
  product 
  of 
  erosion 
  on 
  

   land, 
  much 
  of 
  the 
  material 
  coming 
  from 
  areas 
  of 
  Monterey 
  shale. 
  

   Fresh-water 
  or 
  possibly 
  brackish-water 
  conditions 
  may 
  have 
  pre- 
  

   vailed 
  in 
  the 
  latter 
  part 
  of 
  Fernando 
  time. 
  They 
  certainly 
  did 
  for 
  a 
  

   time 
  and 
  locally, 
  at 
  least, 
  when 
  the 
  brackish-water 
  limestone 
  beds 
  

   were 
  formed. 
  

  

  MAIN 
  QUATERNARY 
  PERIOD. 
  

  

  Downward 
  and 
  upward 
  movements 
  of 
  the 
  coastal 
  region 
  were 
  

   probably 
  in 
  progress 
  during 
  the 
  Fernando 
  period, 
  but 
  were 
  intensi- 
  

   fied 
  early 
  in 
  Pleistocene 
  time, 
  and 
  disturbance 
  of 
  the 
  strata 
  along 
  the 
  

   lines 
  influenced 
  by 
  the 
  post-Monterey 
  upheaval 
  took 
  place. 
  In 
  this 
  

   way 
  the 
  mountain 
  ranges 
  were 
  upraised 
  in 
  their 
  present 
  position 
  and 
  

   the 
  Fernando 
  became 
  warped 
  along 
  the 
  lines 
  of 
  further 
  folding 
  in 
  the 
  

   Monterey. 
  

  

  After 
  this 
  uplift 
  erosion 
  set 
  in 
  and 
  eventually 
  removed 
  the 
  Fer- 
  

   nando 
  from 
  some 
  parts 
  of 
  the 
  region 
  over 
  which 
  it 
  had 
  formed 
  a 
  

   thick 
  covering. 
  The 
  mountain 
  regions 
  were 
  worn 
  into 
  rugged 
  shapes, 
  

   Santa 
  Maria 
  and 
  Santa 
  Ynez 
  rivers 
  developed 
  graded 
  valleys, 
  and 
  

   the 
  sea 
  planed 
  off 
  the 
  coast 
  extensively 
  by 
  cutting. 
  During 
  the 
  same 
  

   period, 
  however, 
  land 
  building 
  over 
  this 
  region 
  was 
  in 
  progress 
  as 
  the 
  

   result 
  of 
  differential 
  movements 
  of 
  the 
  coast. 
  The 
  great 
  resultant 
  

   changes 
  of 
  level 
  in 
  post-Fernando 
  time, 
  as 
  indicated 
  by 
  the 
  records, 
  

   were 
  a 
  pretty 
  general 
  depression 
  to 
  a 
  depth 
  of 
  1,100 
  to 
  1,200 
  feet, 
  and 
  

   locally 
  to 
  at 
  least 
  1,400 
  feet; 
  and 
  a 
  later 
  uplift 
  to 
  the 
  present 
  

   level. 
  These 
  movements 
  were 
  probably 
  gradual 
  and 
  continuous, 
  

   but 
  not 
  sufficiently 
  slow 
  to 
  allow 
  the 
  formation 
  of 
  deposits 
  of 
  great 
  

   thickness. 
  During 
  these 
  movements 
  the 
  sea 
  cut 
  into 
  the 
  land 
  as 
  the 
  

   water 
  encroached 
  and 
  receded, 
  forming 
  terraces 
  inclined 
  toward 
  the 
  

   ocean, 
  and 
  beach 
  and 
  shallow-water 
  sediments 
  were 
  laid 
  down 
  as 
  thin 
  

   coatings 
  over 
  the 
  newly 
  planed 
  surfaces. 
  These 
  deposits 
  were 
  prob- 
  

   ably 
  formed 
  as 
  the 
  land 
  rose. 
  During 
  the 
  periods 
  of 
  depression 
  the 
  

   streams 
  built 
  up 
  deposits 
  of 
  gravel, 
  sand, 
  and 
  clay 
  at 
  different 
  levels, 
  

   giving 
  rise 
  to 
  extensive 
  terraces 
  and 
  to 
  filled 
  valleys. 
  Great 
  deposits 
  

  

  