Tar seeps have been recognized in the region from prehistoric times, and also the Indigenous American inhabitants of The l. a. basin utilised the tar for waterproofing and also other applications. The Spanish settlers employed it for their lamps, for a sealant for roofs, and as grease for wagon wheels.[9] http://geo-analytics30627.articlesblogger.com/17178419/how-much-you-need-to-expect-you-ll-pay-for-a-good-geosteering