... of time. The KBS, Okote and Chari Members of the Koobi Fora Formation ( Brown & Feibel 1986 ) cover this stratigraphic interval (see Fig. 3 , below). Numerous tuffaceous layers occur within this part of the sequence, especially in the Okote Member, but variability in composition of the tuffs...

... Okote Member 83-1647 83-1645 Blk Pumice Tuff Koobi Fora Tuff L. K. Fora Tuff L. Ileret Tuff N. Ileret Tuff Okote Tuff KBS Member L. Okote Tuff Kimire Tuff White Tuff Orange Tuff Malbe Tuff 83-1629 77- 13 83-1407 KBS Tuff Burgi Member Lorenyang Tuff 80-173 80-276 80-275 82-1261 Burgi Tuff Tulu Bor Member...

... belong to Members H, J, and K of the Shungura Formation ( de Heinzelin 1983 ), to the KBS and Okote Members of the Koobi Fora Formation ( Bowen & Vondra 1973 ; Brown & Feibel 1985, 1986 ), and to the Kaitio and Natoo Members of the Nachukui Formation ( Harris et al . 1988 a , b...

...) between 1.48 ± 0.01 Ma and 1.53 ± 0.01 Ma for the interval from the Lower Ileret Tuff to the Koobi Fora Tuff in the lower part of the Okote Member of the Koobi Fora Formation ( Fig. 3 ). Thus, the suggested correlations based upon age are consistent with the stratigraphic and compositional correlations...

...Jennifer E. Hargrave; Melissa K. Hicks; Christopher A. Scholz A bstract : Lake Turkana, northern Kenya, serves as a long-lived end-member extensional basin that preserves a volcanically mediated, mixed siliciclastic and carbonate system. Stratigraphic data from the southeastern margin of Lake...

... , doi: 10.1007/978-90-481-9956-3_3 Getty Conservation Institute ( 2011 ) Report on the Partial Re-Excavation of the Laetoli Hominid Trackway, Site G . Getty Conservation Institute , 53 pp Hatala KG and 10 coauthors ( 2017 ) Hominin track assemblages from Okote Member deposits...

... in the East African Pliocene: An Assessment of the Faunal Evidence . Springer , Dordrecht , pp 129 - 157 , doi: 10.1007/978-1-4020-3098-7_6 Bobe R , Carvalho S ( 2019 ) Hominin diversity and high environmental variability in the Okote Member, Koobi Fora Formation, Kenya . Journal...

... squares method. Table 1 presents chemical compositions of the tourmalines considered in the analysis of thermally induced structural changes. These tourmalines represent various members of the schorl-dravite series, both poor and rich in Fe 3+ and Al, and additionally revealing variable...

... contrast between the distribution of Acheulian and Oldowan sites has also been observed at Koobi Fora in Kenya between Okote Member and KBS Member archaeological sites, respectively ( Rogers et al., 1994 ). Carbonate samples were crushed and roasted under vacuum at 400–450 °C in order to pyrolize...

...://doi.org/10.1007/978-1-4020-4410-6_18 . Bobe , R. , and Carvalho , S. , 2019 , Hominin diversity and high environmental variability in the Okote Member, Koobi Fora Formation, Kenya : Journal of Human Evolution , v. 126 , p. 91 – 105 , https://doi.org/10.1016/j.jhevol.2018.10.012...

... to be set out very clearly ( Fig. 5 ). Where member boundaries are placed at correlative tuffs, they are of the same age, and in most instances that age has now been measured. Directly measured basal ages are absent only for the Okote Member of the Koobi Fora Formation, and Members E, G, H and J...

... ( Figs. 3 G, H). The Galinge tourmaline is compositionally classified into the calcic- and alkali-groups in terms of the Ca, Na + K, and □ contents ( Fig. 4 B). Both Tour-I and Tour-II are intermediate members of the dravite-uvite solid solution series enriched in Fe ( Fig. 4 C). A theoretically...

.../bathonian uplift of the Yorkshire Basin . Proceedings of the Yorkshire Geological Society , 42 , 461 – 482 , https://doi.org/10.1144/pygs.42.3.461 Lepre , C.J . 2017 . Crevasse-splay and associated depositional environments of the hominin-bearing lower Okote Member, Koobi Fora Formation (Plio...

... Al 6 Si 6 O 18 (BO 3 ) 3 OH 4 , <20%], olenite [NaAl 3 Al 6 Si 6 O 18 (BO 3 ) 3 O 3 OH, <20%], and uvite [CaMg 3 MgAl 5 Si 6 O 18 (BO 3 ) 3 OH 4 , <10%] end-members (a table with all EMP analyses reported in this study is available as supplementary material 1 ). This asymmetry...

..., dolomites, and skarns. In contrast, dravite is not typical of common granitic pegmatite environments, where schorl-to-foitite and elbaite members of the tourmaline supergroup are the most widespread ( e.g. , London 2008 ). Magnesium-rich members of the schorl–dravite solid-solution series occur only in very...

... of gold – quartz – tourmaline veins of the Okote area, southern Ethiopia: implications for gold exploration . Mineral. Petrol. 75 , 101 – 122 . Desbois G. Ingrin J. ( 2007 ): Anisotropy of hydrogen diffusion in tourmaline . Geochim. Cosmochim. Acta 71 , 5233 – 5243...

..., and Robert F. Ylagan 157 A solution to the crystal structures of bismutite and beyerite— J.D. Grice 693 The use of end-member charge-arrangements in defining new mineral species and heterovalent substitutions in complex minerals— F.C. Hawthorn 699 Hongshiite, PtCu, from itabirite-hosted Au–Pd...

.... 2006 ). A number of Turkana Basin tuffs contain pumice clasts that host feldspar (typically anorthoclase) crystals, which are the primary target for 40 Ar/ 39 Ar geochronology. Ages are available for c. 40 Omo Group tuffs, ranging from 4.23 ± 0.01 (2 σ ) Ma (unnamed tuff, Apak Member...

..., and genesis of gold mineralization in the Okote area, southern Ethiopia— D.J. Deksissa and C. Koeberl 307 HFSE, REE, and PGE geochemistry of three sedimentary rock-hosted disseminated gold deposits in southwestern Guizhou Province, China— Z. Bao, Z. Zhao, J. Guha, and A.E. Williams-Jones 363...