Because of very erratic availability of internet service (connection is basically only available between 05.00-06.00 a.m. here a three in one update. During the past days we first experienced a half day of serious rain, not motivating us to go out, and making the roads very difficult to navigate. In the afternoon we explored the area to the southeast of Talisayan, and found several outcrops with either friable Operculina packstones or a more marly facies, in which evidence of past presence of abundant mollusks was frequently present. Finding fossil donuts (the LBF Amphisorus) was a highlight for me.
Wednesday we returned to Tanjung Redeb to get permission to work and drive in yet another large coal mine, Berau Coal. On the way we had a further look on the basement rocks from the Danau formation that we already saw on the way down. We saw a nice succession of ophiolitic (old ocean floor) and folded cherts and radiolarites, forming the basement of the basin on which the Cenozoic sediments that we are after were deposited. Somewhere during the Early Cretaceous this ocean floor got accreted to the Borneon craton, only to subside again somewhere during the Middle Eocene.
Today we would get our health and safety induction in the mining office, but in the morning we did a brief visit to a site where we had seen nice carbonates outcropping before, but the owner did not fully appreciate our presence. After Fauzie and Aries (who joined us yesterday) spoke with the Kepala dessa we drove in again and discovered beautiful Early Oligocene Nummulites and Cycloclypeus faunas. Possibly even rarer, but certainly less well preserved, was a Nummulites javanus with coral fauna in recristallised Middle Eocene black limestone. Hopefully we will see more of this tomorrow in the mining area.
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