Himmatnagar Sandstone (lower to middle Cretaceous) is exposed in between Sabarmati River in the west to Vantada in the east around Himmatnagar Town in north Gujarat, India. The sequence is divisible in two members: The lower member is 65 m thick, mostly massive, horizontally stratified to hummocky stratified with abundant plant and trace fossils in assorted shales and sandstones. The upper member is ~ 12 m thick, cross–stratified and medium to coarse grained–gritty to cobbly in nature. Six lithofacies have been identified in the sequence, viz. 1. grey wacke (GW), 2. silty–shale (SS), 3. cross–stratified sandstone (CS), 4. horizontally stratified sandstone (HSS), and 5. planar cross–stratified sandstone (PCS) in the lower member; and 6. gritty–cobbly cross–stratified sandstone (GCCS) in the upper member. The lower member consists of plant fossils which are poor to moderately preserved and transported. The silty–shale lithofacies contains plant fossils (Pagiophyllum, Brachyphyllum, Gleichenia, Araucarites, circinate vernation of ferns, Williamsonia flower, twigs, petrified wood, conifer and its cone, etc.), body fossil (insect wing) and trace fossils (Skolithos, Monocraterion, Psilonichnus, Thalassinoides, Chondrites, Planolites, Palaeophycus, Calycraterion, Circulichnus, Ophiomorpha, Phoebichnus, etc.). In the cross–stratified sandstone lithofacies, body fossils (mainly fragmented bivalves, plant fossils (Weichselia reticulata, Matonidium indicum, Ptilophyllum, cycadean frond and fossil wood) and trace fossils (Monocraterion, Chondrites, Calycraterion, Thalassinoides, Psilonichnus and Skolithos) are recognized. On the other hand, in horizontally stratified sandstone lithofacies plant fossils (Sphenopteris, Pagiophyllum, Gleichenia, Elactocladus, Brachyphyllum, ferns, petrified wood, etc.) and trace fossils (Skolithos, Ophiomorpha, Psilonichnus, Monocraterion, Arenicolites, Diplocraterion, Thalassinoides, Teichichnus, Palaeophycus, Planolites, etc.) are present. While, large crustacean and vertebrate burrows, Skolithos, Thalassinoides, Ophiomorpha, etc are found in planar cross–stratified sandstone lithofacies. The trace fossils belong to Psilonichnus, Skolithos and Cruziana ichnofacies as per Seilacher (1967). The member also contains wedge shape geometry of beds similar to tidal partings as well as ridge and runnel structures, low–angle to hummocky cross–stratification, herringbone structure and parting lineation. Here, north to northeast palaeo–current direction is indicated by cross–stratification in the member. All these features lead to the depositional environment, which seems to be foreshore–tidal flat to middle shoreface for the lower member of the sequence. The upper member is composed of trough cross–stratified sandstones showing prominently southwest to south palaeo–current direction with angular to sub–rounded pebbles and cobbles of underlying rocks and fossil wood with lower erosional contact and channel structures at places. Based on above characteristics, depositional environment of upper member can be interpreted from estuarine to fluvial.

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On the basis of distinct lithologic features such as composition, grain size, bedding characteristics and sedimentary structures, six facies were identified in Callovian to Oxfordian rocks exposed southwest of Bhuj, Kachchh. They are interbedded calcareous shale-siltstone (ICSSF), limestone (LF), ferruginous sandstone (FerSF), felspathic sandstone (FelSF), grey shale (GSF) and oolitic limestone (OLF) facies. The rich and highly diversified trace fossils reveal a wide range of animal behaviours represented by dwelling, feeding, crawling and resting structures. Horizontal feeding structures are found abundantly in all lithofacies indicating low wave and current energy and deposition of poorly sorted muddy to sandy sediments. A few coarse layers containing Arenicolites, Ophiomorpha and Skolithos indicate the presence of opportunistic animals (due to their first appearance under harsh conditions) under -intermittently moderate wave and current energy or storm wave conditions (due to coarse grain size and dominance/presence of only vertical trace fossils) in the shoreface zone. Taenidium occurs mainly in the lower shoreface to transitional zone suggesting low to moderate energy conditions. Thalassinoides occurs in middle to lower shoreface settings under relatively low-energy conditions. Zoophycos represents offshore environment, where it occupies the deepest bioturbation levels. The characteristic lithofacies and assemblages of trace fossils in the rocks of the Chari/Jumara Formation indicate a depositional environment fluctuating from the upper shoreface to offshore zone.