@article{TomasZitzmannHomannetal.2010,
  author    = {Tomas, Sara and Zitzmann, Max and Homann, Martin and Rumpf, Michael and Amour, Frederic and Benisek, Merle-Friederike and Betzler, Christian and Mutti, Maria},
  title     = {From ramp to platform : building a 3D model of depositional geometries and facies architectures in transitional carbonates in the Miocene, northern Sardinia},
  issn      = {0172-9179},
  doi       = {10.1007/s10347-009-0203-7},
  year      = {2010},
  abstract  = {The depositional geometry and facies distribution of an Early Miocene (Burdigalian) carbonate system in the Perfugas Basin (NW Sardinia) comprise a well-exposed example of a transition from a ramp to a steep-flanked platform. The carbonate succession (Sedini Limestone Unit) is composed of two depositional sequences separated by a major erosional unconformity. The lower (sequence 1) records a ramp dominated by heterozoan producers and the upper (sequence 2) is dominated by photozoan producers and displays a gradual steepening of the depositional profile into a steep- flanked platform. This paper shows the process of creating a digital outcrop model including a facies model. This process consists of combining field data sets, including 17 sedimentary logs, and a spatial dataset consisting of differential global positioning system data points measured along key stratigraphic surfaces and sedimentary logs, with the goal of locking traditional field observations into a 3D spatial model. Establishing a precise geometrical framework and visualizing the overall change in the platform geometry and the related vertical and lateral facies variations of the Sedini carbonate platform, allows us to better understand the sedimentary processes leading to the geometrical turn- over of the platform. Furthermore, a detailed facies modeling helps us to gain insight into the detailed depositional dynamics. The final model reproduces faithfully the depositional geometries observed in the outcrops and helps in understanding the relationships between facies and architectural framework at the basin scale. Moreover, it provides the basis to characterize semiquantitatively regional sedimentological features and to make further reservoir and subsurface analogue studies.},
  language  = {en}
}
@article{TomasHomannMuttietal.2013,
  author    = {Tomas, Sara and Homann, Martin and Mutti, Maria and Amour, Frederic and Christ, Nicolas and Immenhauser, Adrian and Agar, Susan M. and Kabiri, Lahcen},
  title     = {Alternation of microbial mounds and ooid shoals (Middle Jurasssic, Morocco) - response to paleoenvironmental changes},
  series = {Sedimentary geology : international journal of applied and regional sedimentology},
  volume    = {294},
  journal   = {Sedimentary geology : international journal of applied and regional sedimentology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0037-0738},
  doi       = {10.1016/j.sedgeo.2013.05.008},
  pages     = {68 -- 82},
  year      = {2013},
  abstract  = {The occurrence of neritic microbial carbonates is often related to ecological refuges, where grazers and other competitors are reduced by environmental conditions, or to post-extinction events (e.g. in the Late Devonian, Early Triassic). Here, we present evidence for Middle Jurassic (Bajocian) microbial mounds formed in the normal marine, shallow neritic setting of an inner, ramp system from the High Atlas of Morocco. The microbial mounds are embedded in cross-bedded oolitic facies. Individual mounds show low relief domal geometries (up to 3 m high and 4.5 m across), but occasionally a second generation of mounds exhibits tabular geometries (<1 m high). The domes are circular in plan view and have intact tops, lacking evidence of current influence on mound preferred growth direction or distribution patterns, or truncation. The mound fades consists almost entirely of non-laminated, micritic thrombolites with branching morphologies and fine-grained, clotted and peloidal fabrics. Normal marine biota are present but infrequent. Several lines of evidence document that microbial mound growth alternates with time intervals of active ooid shoal deposition. This notion is of general significance when compared with modern Bahamian microbialites that co-exist with active sub-aquatic dunes. Furthermore, the lack of detailed studies of Middle Jurassic, normal marine shallow neritic microbial mounds adds a strong motivation for the present study. Specifically, Bajocian mounds formed on a firmground substratum during transgressive phases under condensed sedimentation. Furthermore, a transient increase in nutrient supply in the prevailing mesotrophic setting, as suggested by the heterotrophic-dominated biota, may have controlled microbial mound stages.},
  language  = {en}
}