Core Descriptions

UNOCAL CORPORATION
MCKITTRICK FRONT 415
CORE DESCRIPTIONS

EPOCH WELL LOGGING, INC.

Core #1

1200' -1220'
DIATOMACEOUS MUDSTONE - dark yellow-brown to dusky yellow-brown; soft to slightly firm; poor to moderate induration; dull to sparkling luster; grainy to gritty texture; slightly punky; clay rich; abundant diatom frustules; frustules commonly filled with dark brown clay; common fracture with clay rich fracture fill material; occasional fish scales; low density; weak trace wood debris; common tarry oil blebs on fracture surfaces; moderate to strong petroleum odor; iridescent oil sheen when immersed in water; strong gold to yellow-gold sample fluorescence; instant opaque brownish yellow-orange to yellow-green cut fluorescence; dark amber to brown visible cut; streaming gold to yellow-orange residual cut fluorescence.

Core #2

2210'
SHALE - olive black; very firm, brittle; very good fissility; breaks in thin subparallel layers; slightly grainy to gritty texture; earthy to slightly sparkling luster; noncalcareous; trace relict forams; slight petroleum odor; patchy dull yellow-gold sample fluorescence; moderately fast, streaming milky yellow cut fluorescence; straw visible cut; light yellow-orange residual fluorescence.

2214'
MUDSTONE/SHALE - light olive gray; firm to hard; well indurated; massive to weakly fissile; common off white thin laminations; slightly arenaceous texture; dull earthy luster; abundant scattered relict microfossils; trace diatom casts; trace sulfides: no distinct odor; trace dull yellow sample fluorescence; slightly streaming milky yellow-white cut fluorescence; pale straw visible cut.

2217'
SHALE - live olive gray to olive gray; firm, brittle; fair fissility; occasional microlaminations; gritty to arenaceous texture: dull earthy luster; occasionally sparkling with disseminated sulfides appearing to replace microfossil relicts; abundant forams, rare fish scales; trace dull yellow sample fluorescence; fast diffuse milky white cut fluorescence; pale straw visible cut; light yellow-orange residual cut fluorescence; no odor.

2220'
SHALE - light olive gray; hard; well indurated; poorly fissile grading to mudstone; arenaceous texture; dull earthy luster; noncalcareous; slightly fewer foram inclusions; trace sulfides and fish scales; spotty pale yellow sample fluorescence; very slow light yellow translucent cut fluorescence; light yellow residual cut fluorescence; very pale straw visible cut; lacks distinct petroleum odor.

2223'
SHALE - light olive gray; firm to hard; moderately good fissility; abundant very thin noncalcareous white laminations; gritty to grainy texture; earthy luster; increased diatoms and diatom casts; slightly decreased forams and sulfides; no visible fish scales; trace dull gold-yellow sample fluorescence; fast moderately strong yellow-white cut fluorescence; light yellow-orange residual fluorescence; straw visible cut.

2226'
SHALE - light olive gray; very firm; poorly fissile; grades to diatomaceous mudstone; common white microlaminations; rough, silty texture; dull earthy luster overall with occasional sparkling sulfides; scattered forams; strong trace diatoms; trace pale yellow sample fluorescence; very slow, weak yellow cut fluorescence; light yellow residual cut fluorescence; no odor or visible stain.

2230'
SHALE - pale yellow-brown to light olive gray; firm, tough; poor to fair fissility; less frequent microlaminations; rough, hackly texture; dull luster; diatomaceous; abundant scattered forams and few sulfides; trace dull yellow-gold sample fluorescence; very slow streaming weak yellow cut fluorescence.

Core #3

3850'
SHALE - olive black; very siliceous; hard to very hard; occasionally fractured; poor fissility; abundant relict forams; rough texture; earthy to opalescent luster; calcareous; occasional foram casts which contain oil; weak odor; spotty light yellow sample fluorescence; slow streaming milky yellow cut fluorescence; light yellow residual cut fluorescence.

3851.5'
SHALE - olive black, dusky yellow-brown; very hard; poor fissility; numerous tan microlaminations; one calcite healed fracture; rough texture; resinous luster; abundant relict forams; occasional black fecal pellets/sporbo; no distinct odor; spotty dull yellow-orange sample fluorescence; fast, streaming, moderately strong white-yellow cut fluorescence; light yellow residual cut fluorescence.

3854.5'
SHALE - dusky yellow-brown; very hard; very poor fissllity grading to mudstone; very well indurated; occasional filled apparent fractures; silty to slickenside appearance, dull earthy to resinous luster; calcareous; abundant foram tests and casts; occasional vugs and veins with heavy oil bleeding out; trace sporbo; very weak odor; trace dull yellow-orange sample fluorescence; moderately fast, diffuse to streaming light milky yellow cut fluorescence; light yellow residual cut fluorescence; straw visible cut.

3859'
SHALE - olive black; very hard; very poor fissility; few tan calcareous laminations; abundant slickenside fracture surfaces with occasional free oil; occasional preserved and relict fora-s; weak trace phosphatic nodules; overall rock is calcareous; smooth to silty texture; dull to shiny luster on slickenside surfaces; weak odor; trace dull yellow-orange sample fluorescence; fast streaming to diffuse pale yellow cut fluorescence; light yellow residual cut fluorescence; very pale straw visible cut.

Core #4

4809'
SHALE - dusky brown to yellow-brown; firm to hard; moderate to well indurated; slightly sparkling luster; grainy to abrasive texture; very calcareous; abundant forams; moderate to good uneven fissility; very finely laminated; common fracture surfaces exhibiting well developed clay rich slickensides; occasional forams have been pyritized; no visible stains; weak trace odor; very pale yellow sample fluorescence; moderately fast, streaming to diffuse translucent to slightly opaque green-yellow cut fluorescence; pale yellow residual cut fluorescence; pale straw visible cut.

4812'
SHALE - dusky brown to yellow-brown; firm to hard; moderate to well indurated; slightly sparkling luster; grainy to abrasive texture; very calcareous; slightly decreased abundant of forams; moderate to good uneven fissility; very finely laminated; common fracture surfaces exhibiting well developed clay rich slickensides; slickensides exhibit strong calcite mineralization; occasional forams have been pyritized; no visible stains; weak trace odor; very pale yellow sample fluorescence; moderately fast, streaming to diffuse translucent to slightly opaque green-yellow cut fluorescence; pale yellow residual cut fluorescence; very pale straw to clear visible cut.

4815'
SHALE - dusky brown to yellow-brown; firm to hard; moderate to well indurated; sllghtly sparkling luster; grainy to abrasive texture; very calcareous; increase in abundance of forams relative to sample at 4812'; moderate to good uneven fissility; very finely laminated; common fracture surfaces exhibiting well developed clay rich slickensides; slickensides are highly polished and contorted; no visible stains; weak trace odor; very pale yellow sample fluorescence; moderately fast, streaming to diffuse translucent to slightly opaque green-yellow cut fluorescence; pale yellow residual cut fluorescence; clear visible cut.

4818'
SHALE - light brown to dusky brown; hard; moderate to well indurated; very grainy texture; slightly sparkling luster; common foram hash; laminations less well defined; minor trace possible fish scales; becoming increasingly silty; generally lacks discernible structural features; no visible stains; weak trace odor; very pale yellow to yellow-orange sample fluorescence; fast, streaming to diffuse, increasingly opaque green-yellow cut fluorescence; weak to slightly streaming yellow residual cut fluorescence; straw visible cut.

4821'
SHALE - light brown to dusky brown; hard; moderate to well indurated; very grainy texture; slightly sparkling luster; appears to be grading to foram rich siltstone; common foram hash; trace pyritized forams and increased abundance of forams; laminations less well defined; minor trace possible fish scales; becoming increasingly silty; generally lacks discernible structural features; no visible stain; weak trace odor; pale yellow sample fluorescence; slightly slow to moderately fast, streaming to diffuse, translucent green-yellow cut fluorescence; pale yellow residual cut fluorescence; clear visible cut.

4824'
LIMESTONE - moderate brown to gray-brown; very hard; clay rich slickensides reoccurring; strong sparkling luster; sucrosic texture; common white secondary calcite veinlets; slightly argillaceous; dense; minor vugs from dissolution of foram inclusions; minor trace spotty brown oil stain; weak trace odor; moderately bright, patchy yellow sample fluorescence; fast, streaming opaque green-yellow cut fluorescence; pale yellow-orange residual cut fluorescence; pale straw visible cut.

4828'
SHALE - gray-black to olive black; hard; well indurated; extremely fine grained; trace forams; slightly sparkling luster; finely abrasive texture; very finely laminated; minor trace spotty brown oil stain; weak trace odor; moderately bright, patchy yellow sample fluorescence; fast, streaming, opaque green-yellow cut fluorescence; pale yellow-orange residual cut fluorescence; pale straw visible cut.