﻿74 
  SANTA 
  MARIA 
  OIL 
  DISTRICT, 
  CALIFORNIA. 
  

  

  It 
  la 
  therefore 
  possible 
  thai 
  in 
  the 
  Santa 
  Maria 
  district 
  the 
  gas 
  pres- 
  

   sure 
  is 
  t 
  he 
  chief 
  agent 
  in 
  giving 
  the 
  oil 
  mobility, 
  and 
  that 
  the 
  condition 
  

   of 
  t 
  be 
  rocks 
  is 
  ( 
  lie 
  chief 
  factor 
  that 
  controls 
  the 
  matter 
  of 
  w 
  here 
  the 
  oil 
  

   Is 
  stored 
  most 
  abundantly. 
  Hydrostatic 
  pressure 
  may 
  not 
  play 
  an 
  

   important 
  part. 
  The 
  especially 
  large 
  accumulations 
  in 
  anticlines 
  

   may 
  be 
  accounted 
  for 
  primarily 
  by 
  the 
  cavities 
  offered 
  by 
  the 
  strata 
  

   along 
  upward 
  folds, 
  and 
  secondarily 
  by 
  the 
  presence 
  of 
  less 
  pervious 
  

   beds 
  arching 
  over 
  such 
  folds 
  and 
  affording 
  favorable 
  conditions 
  for 
  the 
  

   confinement 
  of 
  oil 
  and 
  gas 
  tending 
  to 
  escape. 
  Lesser 
  stores 
  of 
  oil 
  may 
  

   occur 
  at 
  other 
  points 
  within 
  the 
  formation. 
  

  

  INDICATIONS 
  OF 
  OIL. 
  

  

  The 
  chief 
  criteria 
  for 
  judging 
  as 
  to 
  the 
  presence 
  or 
  absence 
  of 
  oil 
  in 
  

   appreciable 
  quantities 
  in 
  this 
  region 
  have 
  been 
  the 
  attitude 
  of 
  the 
  beds, 
  

   their 
  position 
  in 
  the 
  series, 
  and 
  the 
  surface 
  indications. 
  Other 
  minor 
  

   evidences 
  of 
  a 
  local 
  nature 
  have 
  also 
  been 
  taken 
  into 
  account. 
  In 
  

   drawing 
  conclusions 
  from 
  structural 
  indications 
  anticlines 
  have 
  been 
  

   considered 
  as 
  the 
  chief 
  factors 
  favoring 
  accumulation, 
  inasmuch 
  as 
  the 
  

   oil 
  appears 
  to 
  have 
  gathered 
  in 
  them 
  in 
  a 
  majority 
  of 
  the 
  proved 
  occur- 
  

   rences 
  in 
  this 
  district, 
  other 
  conditions 
  being 
  favorable. 
  The 
  conclu- 
  

   sion 
  has 
  been 
  reached 
  that 
  anticlines 
  afford 
  a 
  fairly 
  trustworthy 
  clew 
  

   to 
  the 
  location 
  of 
  the 
  most 
  important 
  oil 
  deposits. 
  Close 
  folding 
  

   appears 
  to 
  play 
  a 
  part 
  in 
  this 
  district 
  in 
  depriving 
  the 
  rocks 
  of 
  their 
  

   oil, 
  and 
  excessive 
  disturbance 
  and 
  fracturing 
  is 
  unfavorable 
  to 
  its 
  

   retention. 
  But, 
  on 
  the 
  other 
  hand, 
  moderate 
  folding 
  would 
  appear 
  

   to 
  be 
  favorable, 
  if 
  not 
  requisite, 
  for 
  the 
  accumulation 
  of 
  stores 
  of 
  oil, 
  

   and 
  probably 
  the 
  most 
  favorable 
  conditions 
  are 
  afforded 
  by 
  anticlinal 
  

   folds 
  of 
  such 
  sharpness 
  as 
  to 
  render 
  the 
  brittle 
  rocks 
  porous 
  by 
  frac- 
  

   turing, 
  but 
  to 
  leave 
  less 
  pervious 
  arches 
  of 
  more 
  elastic 
  rock. 
  

  

  The 
  second 
  criterion 
  is 
  the 
  statigraphic 
  position 
  in 
  the 
  formation 
  of 
  

   the 
  beds 
  exposed 
  over 
  the 
  area 
  in 
  which 
  oil 
  is 
  sought. 
  As 
  has 
  been 
  

   before 
  stated, 
  the 
  oil-bearing 
  strata 
  occur 
  chiefly 
  in 
  the 
  lower 
  portion 
  

   of 
  the 
  Monterey. 
  Where 
  the 
  outcropping 
  beds 
  belong 
  to 
  the 
  higher 
  

   portion 
  of 
  the 
  formation 
  there 
  is 
  a 
  greater 
  likelihood 
  that 
  the 
  under- 
  

   lying 
  oil-bearing 
  strata 
  have 
  been 
  able 
  to 
  retain 
  their 
  contents 
  than 
  

   where 
  the 
  lower 
  strata 
  have 
  been 
  denuded 
  of 
  the 
  greater 
  part 
  of 
  the 
  

   overlying 
  beds 
  or 
  where 
  they 
  are 
  themselves 
  exposed 
  or 
  partially 
  

   removed. 
  

  

  As 
  regards 
  the 
  third 
  criterion, 
  the 
  chief 
  surface 
  indications 
  are 
  

   afforded 
  by 
  the 
  presence 
  of 
  seepages 
  of 
  oil 
  or 
  tarry 
  material 
  from 
  the 
  

   shales, 
  by 
  asphalt 
  deposits, 
  bituminous 
  shales, 
  and 
  burnt 
  shale. 
  

   Asphalt 
  occurs 
  mainly 
  in 
  three 
  ways 
  — 
  as 
  a 
  mixture 
  of 
  bituminous 
  

   material 
  with 
  sand, 
  due 
  to 
  the 
  absorption 
  by 
  overlying 
  sand 
  deposits 
  

   of 
  seepages 
  from 
  the 
  shale, 
  as 
  hardened 
  fillings 
  of 
  asphalt 
  in 
  cavities 
  

   along 
  joints, 
  and 
  as 
  excessively 
  saturated 
  shale. 
  The 
  burnt 
  shale 
  is 
  

  

  