The Upper Miocene Rocks of the Balearic archipelago (Mallorca, Menorca, Ibiza, Formentera and smaller islands) are commonly flat-lying limestones and dolostones,with only slight tilting and flexure, probably caused by normal and strikeslip faulting in the Late Neogene to Middle Pleistocene. They are composed of three third-order depositional sequences (Pomar et al., 1996):

• The lower sequence, attributed to the Early Tortonian, corresponds to a carbonate ramp with extensive rhodalgal lithofacies and no coral reefs.
• The middle sequence, attributed to the Late Tortonian-Early Messinian, corresponds to well-developed progradational reefal platforms, including the Llucmajor Platform reef complex.
• The upper sequence, assigned to the Messinian, consists of a variety of lithologies including oolites and Stromatolites.

On this web site only the lower and middle depositional sequences are considered and the exercises presented here are focused on the Llucmajor Platform reef complex. This is some 150 m thick and in southwestern Mallorca has prograded laterally over more than 20 km. Between Vallgornera and Cap Blanc in southwest Mallorca it is exceptionally well exposed along both depositional strike and dip directions for some 6 km in vertical sea cliffs and is only slightly deformed by Pliocene–Pleistocene uplift, faulting, and gentle flexure. Discussed below are the facies and stratal geometries of the Llucmajor Platform reef complex outcropping around Cap Blanc. These have been described in detail since 1991 by Pomar, in papers linked to this site.

Pomar, (1991, 1993) Pomar and Ward (1994, 1995, 1999), Bosence et al, (1994), Pomar et al. (1996) and later Pomar (2001) explain how the lagoon facies landward of the reef crest are horizontal beds bounded by erosion surfaces. These lagoonal sediments are formed by skeletal grainstones and packstones with lenses of coral breccia and patch reefs. Outer lagoonal areas in back-reef position are formed by beds of bioturbated skeletal grainstone- packstone with coral patch reefs with an abundaformformformnt contents of red-algae fragments, echinoids, mollusks, benthic foraminifera and coral fragments, as well as minor amounts of Halimeda, planktonic foraminifera, bryozoans, peloids and intraclasts. Coral morphologies in the lagoon facies commonly vary spatially, with larger, hemispherical and columnar forms seaward and smaller hemispherical forms landward. Inner lagoonal areas have fewer and smaller coral colonies and patch reefs, and bioclastic sediments predominate. The inner-lagoonal lithofacies are thin- to medium- Bedded grainstones, packstones and wackestones- mudstones. Skeletal components are miliolids, thin bivalves, peloids and cerithid gastropods. Some layers also contain abundaformformformnt benthic foraminifera or ooids. Ostracods, dasyclad algae, echinoids, Favreina pellets, calcispheres and red algae are less common component. Miliolid grainstones and packstones with vertical root casts are interpreted as mangrove deposits. Stromatolites and muddy sediments with ostracods, Chara, and oncolites characterize the innermost lagoonal facies. Beach deposits with upper shoreface and foreshore facies also are present. In the lagoonal facies thin laminites or gastropod rich wackestone ( restricted facies) rest on the erosional surface and are overlain by packstone, wackestone and grainstone with red algae, echinoids, mollusks, and benthic foraminifera (open lagoon) In the outer lagoonal facies, the basal laminites are overlain by both coral parch reefs and coarse skeletal grainstone (interpatch sediments). As at the reef crest, the upper erosional surface truncates everything, particularly the patch reef corals and the grainstone sediments of the outer lagoon facies. In the lagoonal facies, the basal laminites record the flooding of the platform top and the overlying coral parches record the submergence of the platform to the optimum production conditions. In the lagoonal facies the erosional truncation of the coral patches is interpreted to follow a fall in sea level. The upper shallowing up part of the cycle is missing, and the physical correlation of the erosional surface from the lagoon to the reef core supports this interpretation.

Reef-slope .

distal reef-slope deposits are gently inclined layers of white, chalky calcisiltites and calcarenites (coralline algal, molluskan packstones and grainstones) with bioturbated beds (for details see Pomar et al., 1996).

The distal slope facies pass basinward to bioturbated, fine-grained wackestones. These fine-grained deposits accumulated as the result of carbonate shedding from the shallow-water platform, during periods of sea-level rise, when carbonate production was enhanced in the lagoonal areas. During lowstands of sea level however, carbonate production occurred in off-reefs areas where the light reached the sea floor. In this setting, a sediment dominated by red-algae was produced. This is composed of red-algal grainstone to rhodolithic rudstone or to biostromal layers of laminar or branching red algae. Oysters and pectinids are common. Larger foraminifera (Heterostegina) locally occur, and planktonic foraminifera are present. Coral colonies of Tarbellastraea and/or Porites occur at the top of some Beds. Meter-scale cyclic textural changes in composition are interpreted to record high-frequency cyclicity in this lithofacies. Bioturbated sediments are characteristic although laminations are locally visible. Branching red-algal biostromes also occur within the slope deposits. Based on the coarse-grained texture and abundaformformformnce of red algae it is interpreted that deposition of most of this lithofacies took place in the oligophotic or in the mesophotic zone, with sufficient water energy (currents and storm waves) to winnow away fines (Pomar, 2001). Nevertheless, the platform architecture indicates that this lithofacies was deposited in off-reef, shallow-basin settings, during lowstands of fourth-order relative sea-level cycles. Corals and other shallow-water biota at the top of the internal cycles of this lithofacies are interpreted to represent the lowest positions of relative sea level, within the high-frequency cyclicity. Sufficient light reached the sea floor to allow some corals to grow during these lowstands of sea level (Pomar et al., 1996; Pomar and Ward, 1999; Pomar, 2001).

Fine grained Reef-Slope to Open-Shelf Facies

Response of Platform Architecture to Eustasy

The outcropping facies and stratigraphic geometries form the "sigmoids" of Pomar (1991). These capture several orders of cyclic change in the position of the reefal facies, and stack into progressively larger-scale accretional units of sets, cosets, and megasets. They are interpreted to represent a response to hierarchical orders of cyclic fluctuations in Late Miocene glacioeustatic movement (Pomar, 1991; and Pomar and Ward, 1994, 1995, 1999). The estimated amplitudes of these cycles are respectively less than 15 m, 20-30 m, 60-70 m, and about 100 m. The hierarchy of the cyclicity is interpreted as four orders below that of the 3rd order global cycles of Haq et al. (1987) and has been used to construct the relative sea level curve of Bosence et al (1994) which is used in the simulation movies of the site.

The accretional units of the high-frequency depositional sequences (seventh to fourth order) have similar stratal geometries, boundaries, and facies architectures (see the adjacent figures). Each of these units are composed of horizontal lagoonal beds that pass basinward into reef-core lithofacies with sigmoidal Bedding, through forereef-slope clinoformformformBeds, and then into flat-lying openshelf (or shallow-basin) Beds. The bounding envelopes to the lagoonal and reef-core units are erosion surfaces (submarine and subaerial), which pass basinward into correlative conformities. Many of the basic accretional units are wedge shaped as a result of non-deposition or erosional truncation of the upper part of this accretional unit (lagoon and upper portion of ref-core lithofacies), or both.