摘要：Sedimentation of Aptian-Albian plant particles (Phytoclasts) in sedimentary rocks of Taquari
Member, Riachuelo Formation, Sergipe Basin, Brazil.
The Aptian-Albian sedimentation occurred in the Sergipe Basin is directly related to the progressive separation
of the South American and African continents, resulting in the formation of the South Atlantic Ocean. This
work aims the paleoenvironment interpretation based in the distribution and the processes of sedimentation
of the phytoclasts in the marine environment. For this study were used 118 samples of well GTP-24-SE of
Taquari Member, Riachuelo Formation of Sergipe Basin. The slides were analyzed under the light white
transmitted microscopy, where the components of the phytoclasts group were classified and counted. Moreover,
to access information about the stratigraphical distribution of the phytoclasts, parameters and ratio were
used, such as: % of phytoclasts of the total kerogen, opaque: translucent ratio and % of cuticle of the total of
phytoclasts. Seven types of components of the phytoclasts were recognized: equidimensional opaque, lath
opaque, cuticles, translucent without pits, translucent with pits, fungal hyphae, and membrane. The lath
opaque is the most abundant phytoclast particles (average=49.6%) suggesting a strong transport of terrigenous
components on the marine paleoenvironment. The stratigraphical distribution of the phytoclast frequencies
decreases progressively upward. This reflects an estrangement from the source area as consequence of the
shoreline shift in direction to the continent. Two types of depositional environment are indicated by the kerogen
for the Taquari Member: transition of shelf to basin in time and distal shelf
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