page_title: Cozy Dell Shale
section_title: Type locality and extent
hierarchical_section_title: Cozy Dell Shale / Type locality and extent
caption_attribution_description: English: Bedding in the Cozy Dell Shale; photo by self, Santa Ynez Mountains, CA, 9/26/10.
context_page_description: The Cozy Dell Shale is a geologic formation of middle Eocene age that crops out in the Santa Ynez Mountains and Topatopa Mountains of California, extending from north of Fillmore in Ventura County westward to near Point Arguello, north of Santa Barbara. Because the Cozy Dell easily weathers to a clay-rich soil, it crops out infrequently and generally forms dense stands of chaparral in saddles between peaks and ridges of the more resistant Matilija and Coldwater formations.
context_section_description: The Cozy Dell was first described in 1928 as the middle member of the Tejon Formation. However, Dibblee (1966) reclassified it as a formation, along with the underlying Matilija Sandstone and overlying Coldwater Sandstone. He also named the formation after its type locality at Cozy Dell Canyon, which is located on the south side of Nordhoff Ridge, just north of Ojai in Ventura County.
  The Cozy Dell crops out continuously in the mountains to the north and east of Ojai, where it is exposed along much of the south slope of the Topatopa Mountains in Ventura County, and continues westward along the south slope of Santa Ynez Mountains into Santa Barbara County. Here, it is overlain by younger rocks at San Marcos Pass, on the crest of the Santa Ynez Range, cropping out west of the pass and forming much of the crest north of Goleta. It disappears north of the Santa Ynez Mountains beneath younger formations, and is removed, for the most part, by erosion north of the Santa Ynez River, where it appears at only a few localities. It grades into and is overlain by the Sacate Formation in the western part of its outcrop belt, and dips south beneath the modern California coastal plain in the southern part. Continuing south into the offshore region beneath the Santa Barbara Channel, the Cozy Dell is found in oil wells at Molino field some 13,000 feet (3,962 m) feet below the sea floor.
  The thickness of the formation increases, more or less, from east to west and averages about 1,700 feet (518 m) in the Santa Ynez Mountains. However, thicknesses vary widely, ranging from a maximum of 4,000 feet (1,219 m) west of San Marcos Pass, to 50 feet (15 m) thick in the subsurface of the offshore Hondo Oil Field, and only 350 feet (107 m) thick in the offshore Molino Gas Field, which is located west of Hondo.
caption: Close-up of bedding in the Cozy Dell Shale. Scale is about 10 feet (3 m) across.
exif: {"Image ImageDescription": "", "Image Make": "Canon", "Image Model": "Canon PowerShot SX110 IS", "Image Orientation": "Horizontal (normal)", "Image DateTime": "2010:09:26 10:43:20", "Image YCbCrPositioning": "Co-sited", "Image Tag 0x1001": "3456", "Image Tag 0x1002": "2592", "Image ExifOffset": "2278", "Image Padding": "[]", "EXIF ExposureTime": "1/400", "EXIF FNumber": "4", "EXIF ISOSpeedRatings": "80", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2010:09:26 10:43:20", "EXIF DateTimeDigitized": "2010:09:26 10:43:20", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "5", "EXIF ShutterSpeedValue": "277/32", "EXIF ApertureValue": "4", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "4", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "233/5", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "3456", "EXIF ExifImageLength": "2592", "EXIF FocalPlaneXResolution": "3456000/229", "EXIF FocalPlaneYResolution": "288000/19", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard", "EXIF Padding": "[]", "EXIF OffsetSchema": "4168"}