FIGURE 4. Shallow-marine siliciclastic deposits, Furongian-lower Tremadocian Alfarcito Member, Santa Rosita Formation, Quebrada del Abra Blanca, Jujuy Province. 1. Parasequence showing upper-offshore deposits passing upwards into offshore-transition deposits having more regular intercalations of storm-generated hummocky cross-stratified sandstone and fairweather siltstone. 2. Close-up of upper-offshore deposits shown in 1. Note excellent preservation of interbedded sandstone tempestites in the absence of intense burrowing. The ichnofauna typically present in these deposits is dominated by shallow-tier trilobite trace fossils, such as Cruziana and Rusophycus (arrow), with well-preserved scratch marks. 3. Close-up of the Rusophycus specimen illustrated in 2. Scale bar equals 1 cm.