tag:blogger.com,1999:blog-1953405279736337089.post4536260895108952006..comments2024-03-29T03:21:04.512-06:00Comments on The Coastal Paleontologist: California shark teethRobert Boesseneckerhttp://www.blogger.com/profile/04157434108254005433noreply@blogger.comBlogger5125tag:blogger.com,1999:blog-1953405279736337089.post-76328994464142340422022-08-20T00:18:13.852-06:002022-08-20T00:18:13.852-06:00That’s awesome! Where is the location in Irvine? That’s awesome! Where is the location in Irvine? Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-1953405279736337089.post-27205582389960412462021-05-22T14:50:22.105-06:002021-05-22T14:50:22.105-06:00@ Chris D: that's precisely the argument laid ...@ Chris D: that's precisely the argument laid out above.Robert Boesseneckerhttps://www.blogger.com/profile/04157434108254005433noreply@blogger.comtag:blogger.com,1999:blog-1953405279736337089.post-83186010715765244052021-05-16T08:16:10.303-06:002021-05-16T08:16:10.303-06:00I've always assumed tectonic forces to blame f...I've always assumed tectonic forces to blame for the lack of dense shark tooth sites in California. East coast is a passive margin while the west coast has been in constant change. chris Dnoreply@blogger.comtag:blogger.com,1999:blog-1953405279736337089.post-49415916866221477522011-10-09T12:27:24.123-06:002011-10-09T12:27:24.123-06:00Meredith - I've heard that some of the Montere...Meredith - I've heard that some of the Monterey Fm. localities have yielded quite a few shark teeth, including the old Leisure World localities. Pretty interesting with the Isogomphodon! I've not heard of them being preserved in any NE Pacific rocks.<br /><br />Chuck - This might be a bit oversimplified. Granted, adult lamnids are on average larger than adult carchariniforms, but there are some localities back east where there are more abundant lamniforms, and certain localities in the NE Pacific where carchariniforms are less rare. In the Purisima Formation for example, I would guesstimate that 75-90% of the Carcharodon carcharias teeth are under 3cm long and relatively small. What needs to be done for other rock units (aside from the Purisima Fm., which I did this for in my master's thesis) is to compare the relative proportion of marine mammal bones to shark teeth, and see if there is a difference between various rock units.Robert Boesseneckerhttps://www.blogger.com/profile/04157434108254005433noreply@blogger.comtag:blogger.com,1999:blog-1953405279736337089.post-54460464895693803792011-10-04T10:33:29.114-06:002011-10-04T10:33:29.114-06:00It occurs to me that the size of the shark might h...It occurs to me that the size of the shark might have a lot to do with the number of teeth available to become fossilized. Your Purisima Formation specimens are all from larger sharks, while, if I remember correctly, the genera from the East Coast are all smaller sharks. If you assume the same biomass of sharks/unit sample you might have one shark from the west coast and 4-5 sharks from the East Coast to make up the same biomass. Four or five sharks, even small ones, are going to have many more teeth than one large shark.Chuck Powellhttps://www.blogger.com/profile/10749812068767602325noreply@blogger.com