87 and in seven of the nine sections a unique concentration sequence of the ode - 2394240, Pu 155e, 5 238, 806, , 137.6, 24a 5207p: was found. A long core of entirely pulverized sediment was collected from the center of the Bravo Crater. Three seqments of this 56-cm core (the 0-12, 26-34 and 48-56 cm segments) were cut into 2-cm sections for the radionuclide measurements. The concentrations of radionuclides (Fig. 22) measured in the two lower segments of the core were similar to the uniform concentrations measured in the Zuni Crater core. In the surface 12 cm, however, a well-defined layer of high radionuclide concentrations was centered at the 6-8 cm depth. Elevated concentrations of all radionuclides were measured in this section, which con- tained the highest concentrations of 2385, (8.3 pCi/q), 2075 5 (432 pCi/g) and 606 (306 pCi/g) measured in any Bikini sediments, except for the one higher 2385, concentration (19.0 pCi/g) found in Zuni Crater sediments. The ordering sequence of radionuclide concentrations in different regions in the core differed greatly. The sequence in the 0-2 cm section of the core differed from the sequence in lower sections and from the sequence found in any of the three other grab samples collected across the crater, which individually also differed from each other. In the 2-12 cm region of the core the order in the sections was Bi >Co >Eu >Am >Cs. In the 26-34 region, three of four sections had the order Co > Bi > Eu > Am > Cs and in the 48-56 cm region of the core, the sequence was Co > Am > Eu > Bi > Cs or Co > Am> Bi > Eu > Cs. Since plutonium was only measured in one section in each region, its placement is not included as characteristic of larger regions. The low 2394240, 2385, ratios found in the upper 12 cm of this core, however, illustrates that the origin of these radionuclides was different from those found in the lower regions. The radionuclides measured in the uppermost layers may be remnants from one of the smaller post-Bravo tests conducted in this area. The