Geochronology using {sup 210}Pb is the principal method used to quantify sediment accumulation in rapidly depositing aquatic environments such as lakes, estuaries, continental shelves, and submarine canyons. This method is based on the radioactive decay of {sup 210}Pb with depth in a column of sediment. The decay through time of {sup 210}Pb P(t) is governed by the exponential law P(t) = P{sub 0} exp( -{lambda}t) where P{sub 0} is the surficial concentration at time t = 0, and {lambda} is the decay constant (3.114 {sm_bullet} 10{sup -2} year [yr]{sup -1} for {sup 210}Pb). If the sedimentation rate is constant, then elapsed time t is connected to burial depth x, through x = Vt where V is the sedimentation velocity. Accordingly, P(x) = P{sub 0}exp( -{lambda}x/V). The sedimentation velocity is obtained from an exponential fit to the measured {sup 210}Pb data P(x), with depth x.

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.

Semi-monthly newsletter of Congregation Beth Yeshurun in Houston, including news and events, upcoming services, member announcements, editorials, and other information of interest to congregants. This issue discusses Beth Yeshurun's second night seder and announces the Adult European Religious Overseas Sightseeing trip led by Rabbi Jack and Toby Segal.

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.