The Whittier fault forms the central part of a fault system extending
from the East Montebello fault at Whittier Narrows to the Elsinore fault,
which is traced as far as the Mexican border. The Whittier fault forms a
restraining bend in this fault system, resulting in uplift of the Puente Hills.
The northwestern part of the Whittier fault in the Whittier oil field in the
eastern Los Angeles basin strikes approximately N65��W and dips 70-75��
northeast. The fault is near the range front of the Puente Hills northwest of
Turnbull Canyon, and within the Puente Hills to the southeast.
The central reach of the Whittier fault had normal separation in the
Relizian and Luisian stages of the middle Miocene. From the Mohnian
through Repettian stages of the late Miocene and early Pliocene, little, if any,
offset occurred until the initiation of reverse offset in the Venturian stage of
the late Pliocene. A component of right-lateral strike-slip may have been
added near the end of the Pliocene, coinciding with the formation of the
Elsinore fault. The Workman Hill and Whittier Heights faults may have
formed in the late Pliocene to early Pleistocene, coinciding with the possible
initiation of strike-slip on the Whittier fault. The present sense of slip on the
Whittier fault southeast of the study area is nearly pure right-lateral strike-slip,
with a slip rate of 2-3 mm/yr. The northwestern part of the Whittier
fault has a component of reverse slip of approximately 1 mm/yr. The
amount of strike-slip on this part of the fault was not determined by this
study.
The Rideout Heights, 304, and 184 low-amplitude anticlines formed in
the Whittier oil field area in the late Miocene and early Pliocene. The
Rideout Heights anticline is a southwest-verging fault-propagation fold
trending northwesterly from the mouth of Turnbull Canyon through the
Rideout Heights area. Strata are overturned in the southwest limb of the
fold, and normally dipping in the northeast limb; the fold has been cut along
its hinge by the Whittier fault.
The 304 and 184 anticlines are north-verging and appear to be beddingplane
shear folds in the northeast limb of the La Habra syncline. Recent
strike-slip on the Whittier fault may have reactivated the 184 anticline,
causing uplift of the footwall block south of Turnbull Canyon. North of
Turnbull Canyon, the Whittier fault is at the range front with no evidence of
Quaternary footwall uplift. The 304 anticline could be a fault-propagation
fold from a previously-unknown southwest dipping blind reverse fault south
of the Whittier fault; uplift on this fold could also be the cause of footwall
uplift south of Turnbull Canyon.
Active fault traces, possibly strike-slip, are on or near the Whittier fault
south of Turnbull Canyon, but to the north, recent offsets appear to be
northeast of the Whittier fault in the Puente Hills. These offsets may
represent an attempt of the Whittier fault to straighten itself by bypassing the
restraining bend at Turnbull Canyon. so, this movement is too recent to
offset conglomerate beds more than a few tens of meters. / Graduation date: 1998
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/33340 |
| Date | 26 January 1998 |
| Creators | Herzog, David W. |
| Contributors | Yeats, Robert S. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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