Schematic cross section of the lake dynamics and associated facies (adapted from Bohacs and Carroll, 2000).

<p>Schematic cross section of the lake dynamics and associated facies (adapted from Bohacs and Carroll, 2000).</p

Photomicrographs of the caddisfly cases.

<p>(A) Caddisfly case in cross section. (B) Caddisfly case in cross section. (C) Close view of an ostracod case particle. (D) Close view of a plant-wood fragment. (E) Caddisfly case in cross section with biotite fragments. (F) Caddisfly case in cross section, filled with blocky calcite spar cement. (G) Oblique view of caddisfly case. (H) Caddisfly case in longitudinal section. Ca-calcite; Mi-micrrite; Pl-plant fragment; Os-ostracod; Bt-biotite; Fs-feldspar; CC-caddisfly case.</p

Local geological map overlain on the satellite imagery (modified after Zabotkin et al., 1988).

<p>Refer to the keys for map units and symbols. Fm: formation.</p

Photos of the main facies.

<p>(A) Laminated mudstone facies of the lower interval. (B) Close view of organic-rich, laminated mudstone. (C) Interbedded mudstone, tabular sandstone, siltstone, and marl facies. (D) Pillow lava of the lower interval. (E) Coarsening upward interbedded sandstone, siltstone, and mudstone facies within the upper interval. (F) Climbing ripples of the sandstone facies within the upper interval.</p

Photos of the bioherms.

<p>(A) Mound-shaped bioherm bounded by laminated, organic-rich mudstone. (B) Mound-shaped bioherm bounded by laminated mudstone. (C) Contact between bioherm and underlying mudstone. (D) Wavy laminated structure of the bioherm. (E) Tube-shaped caddisfly cases on the weathered surface of bioherm. (F) Fine laminated internal structure of the bioherm.</p

Caddisfly suborders and families (modified after Wiggins, 2004; Holzenthal et al., 2007).

<p>Caddisfly suborders and families (modified after Wiggins, 2004; Holzenthal et al., 2007).</p

Photomicrographs of the microlaminated micrites.

<p>(A) Hand sample photo of the boundstone. (B) Microlaminated micrite forming finger-like columnar fabrics. (C) Cone shaped microlamination. (D) Crinkled, wavy lamination with inclined surface. (E) Crinkled, wavy lamination. (F) Flocculated micrite grain trapped/bound between laminations. (G) Sphere shaped oncoidal fabric in cross section. (H) Caddisfly case bound by fine laminations. (I) Sphere oncoidal fabric with a plant nuclei. (J) Shelter porosity and its associated cements. (K) Shelter porosity and its associated cements. (K) Shelter porosity and its associated cements. (L) Vugular porosity. (M) Vug porosity and its associated cements. CC-caddisfly case; ML- microlaminated micrite; Mi-micrite matrix; SP- shelter porosity; VP- vugular porosity; OC-oncoid; FM- flocculated micrite; MS- granular microspar; IC-isopachous calcite; BC- blocky calcite; Gy- gypsum; Fi- fibrious calcite.</p

Caddisfly case reconstruction.

<p>(A) Straight caddisfly case. (B) Curved J-shaped caddisfly case. (C) Straight caddisfly case. Cases are lined with plant fragments, ostracod valves, mica, and carbonate rock fragments. Note: Caddisfly case particles are for illustration purpose, not to scale.</p

Caddisfly cases on the hand sample photos.

<p>(A) Straight (black arrow) caddisfly cases on the hand sample. (B) Straight (black arrow and curved (white arrow) caddisfly cases on the hand samples. (C) Straight (black arrow) and curved (white arrow) caddisfly cases on the polished sample. (D) Straight (black arrow) and curved (white arrow) caddisfly cases on the polished sample. (E) Curved (white arrow) caddisfly case on the polished sample. (F) Curved (white arrow) caddisfly case on the polished sample.</p

Tsagaansuvarga Basin location and Mesozoic sedimentary basins of Mongolia.

<p>(A) Tsagaansuvarga Basin location map overlain on the regional digital elevation model. (B) Mesozoic sedimentary basins of Mongolia.</p