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In reply to a discussion paper by Gray and Gordon (2020), we have not provided a full review of alternative literature that a response to a peer-reviewed publication would allow...

Equivalent in principle to type localities and type specimens in biology and paleontology, geological type sections and type localities, whether for sedimentary, metamorphic or igneous units, are critically important sites as long-term reference and research localities and for geo-education of students. Unlike type specimens that are housed in museums or established institutions of learning, most geological type sections and localities are in field settings and, if they are not located in National Parks or other reserves with some legislated protection, run the risk of being destroyed, inundated, buried by earthworks or otherwise modified. The history of the geological sciences in Australia is such that a number of type localities, or stratigraphic type sections, have been destroyed by local government actions, or developers through lack of knowledge of their importance, or lack of knowledge of their existence. Examples of the severe modification or loss of type sections include those of the Maxicar beds, the Tims Thicket Limestone and the Eaton Sand. The UK, a leader in the field of Geoconservation and with a number of global stratotype section and point locations as well as many other type sections identified within its borders, provides models for preserving and managing important geological sites and type sections. Whole-of-government and local governments are involved in the registering and protection of important geological sites. Aspects of the UK model may be adapted to help secure geological type sections and localities in Australia. While some type sections and heritage localities are already protected, to improve the level of protection for more sites we propose a long-term, multi-pronged approach: creation of an inventory of all nominated locations; registration of appropriate sites at Local, State or Federal government levels, where current legislation allows; education of landowners and land managers, both government and non-government to highlight the

Globally significant geoheritage features of the Cliefden Caves area, in the Belubula River Valley between Orange and Cowra in central western New South Wales, comprise a richly fossiliferous shallow-water limestone succession of Late Ordovician age (the Cliefden Caves Limestone Subgroup) overlain by deep-water laminites and allochthonous limestones of the Upper Ordovician Malongulli Formation. Key features of the Ordovician geology of the Cliefden Caves area that have been identified using the Geoheritage Toolkit as being of international significance are the abundance of unique and exceptionally diverse fossils in the Fossil Hill Limestone (forming the lower part of the Cliefden Caves Limestone Subgroup), which supplement detailed interpretation of carbonate-dominated deposition within an Ordovician volcanic island setting. The fossiliferous limestones preserve biostromes and local small bioherms of stromatoporoids and corals, and recurrent in situ and disarticulated/imbricated Eodinobolus shell beds formed in shallow, quiet-water, dominantly muddy carbonate sediments that passed up-sequence to clay-free carbonate environments. These mud-dominated carbonate sediments are interspersed with higher-energy conditions, represented by skeletal, lithoclastic and calcrete-ooid grainstones overlying disconformities, leading to the identification of subaerial disconformities and associated diagenesis in the Fossil Hill Limestone. The Fossil Hill Limestone is succeeded by massive limestones in the middle part of the Cliefden Caves Limestone Subgroup and then, in turn by the Vandon Limestone and the deeper-water graptolitic laminites of the Malongulli Formation—this completes a succession that is rarely preserved in the geological record, further enhancing the geoheritage significance of the Cliefden Caves area.

This issue on Geoheritage and Geoconservation derives from presentations at the Australian Earth Science Convention held at the Adelaide Convention Centre, Adelaide South Australia (June 2016), the Linnaean Society of New South Wales Belubula Conference in Bathurst, New South Wales (September 2015), and an invited keynote contribution that brings together a diversity of papers capturing the breadth and scope of Geoheritage and Geoconservation in Australia...

The Ordovician Daylesford Limestone at Bowan Park and the Fossil Hill Limestone at Cliefden Caves have diagenetic and pedogenic features of microkarst, paleosols and calcrete associated with subaerial disconformities in their stratigraphic sequences, all of which, as an ensemble, have global geoheritage significance. The original shelly limestones, lime mudstones, and coralline limestones have selectively dissolved to form vugular limestone whose cavities have filled with sparry calcite and/or crystal silt. The limestones also have been calcretised to develop massive and laminar calcrete and calcrete ooids. Below disconformity surfaces are bleached limestone, crystal-silt and spar-filled fossil moulds and enlarged moulds, micro-breccia-filled moulds and fissures filled with crystal silt, calcrete pellets and calcrete ooids. The disconformity surfaces are irregular or undulating interfaces between lithologies, fissures and fissure-fills, and calcrete. Above disconformities there are limestone lithoclasts, remanié fossils, calcreted limestone, veined limestone, calcrete ooids, laminated calcrete, lithoclast grainstone, or calcrete-ooid grainstone, and lithoclasts with fossils moulds filled with crystal silt and/or spar. The lithological, stratigraphic and possibly landscape differences, make the subaerial diagenesis/pedogenesis in the Daylesford Limestone subtly different to that of the Fossil Hill Limestone. Subaerial disconformities and associated diagenesis/pedogenesis, as recorded in these formations, are not widely reported globally nor well represented in Ordovician limestones. The microkarst features provide insights into the types of subaerial diagenesis/pedogenesis during the Ordovician and into climate, landscape setting, paleohydrology, and groundwater/rainwater alkalinity. Consequently, the story of the Ordovician microkarst, paleosols and calcrete ooids is unique and globally of geoheritage significance as examples of subaerial alteration in an ancient hi

In identifying sites of geoheritage significance, commonly there has been an emphasis on the larger-scale features. However, the story of geology and the significant features that are critical to unravel geological processes and geological history are commonly small in scale. This contribution focuses on bubble sand and bubble-sand structures as features that are small-scale but nonetheless important to geology, and hence are of geoheritage significance. Bubble sand and bubble-sand structures are ubiquitous on modern beaches and tidal flats, occurring in the uppermost tidal zone of sandy beaches, as a distinct layer in a shoaling beach-to-dune stratigraphy, and are a diagnostic indicator of upper-tidal conditions where a rising tide and a concomitantly rising water-table interacts with the upper swash-zone wave processes. On sandy tidal flats, bubble sand and bubble-sand structures may occur in the mid- to upper-tidal zones; here they are also diagnostic indicators of tidal conditions, forming during a rising tide where a rising water-table forces air upwards to be trapped in moist sand. If found in ancient sequences, bubble-sand structures are a powerful environmental indicator of tidal conditions and, for beach sequences, an indicator of the high-tide level and sea level. Bubble-sand structures have been found in a number of ancient sequences throughout the geological record as far back as the Neoproterozoic, e.g. within beach-to-dune stratigraphy in Pleistocene limestones of the Perth Basin and in southeastern USA, and in tidal-flat sands of the Mesozoic Broome Sandstone of the Canning Basin. The bubble-sand structure is a significant geological tool for use in paleo-environmental and paleo-oceanographic reconstructions, and determination of the position of a paleo-water-table. Given the rarity of their preservation, these occurrences of bubble-sand structures are of geoheritage significance in their own right and, depending on age of sequence and how common they

In the growing field of Geoheritage, Geoconservation, Geo-education and Geotourism, there is a need to manage sites of geoheritage significance. While there is some great geology in nature available to appreciate for scenic value, education, tourism and research, many locations need to be protected from people and commercialism (e.g. the Iridium layer at the K/T boundary in Gubbio, Italy, the Ediacaran fauna in South Australia, the Burgess Shale in Canada or the zircon crystals at Jack Hills, among many others), and some locations need hazard management to protect people (e.g. continuously collapsing cliffs that have potential to be hazardous via rock falls, or slippery slopes, or high cliffs that are treacherous, or ‘king waves’ on rocky shores). The concept of the ‘8Gs’ is intended as a policy-style guidance that logically and progressively links Geology and Geoheritage through a series of steps to Geo-education and Geotourism. There is a logical progression from Geology the Science, through to Geoheritage and the identification of sites of geoheritage significance, to the establishment of Geosites/Geoparks, Geoconservation, leading to Geomanagement, Geo-education and Geotourism. Geomanagement needs to be undertaken prior to the use of sites for Geo-education and Geotourism. In relation to Geomanagement, sites need to be investigated for safety issues, and for the protection of their geological features. Geodiversity, the eighth ‘G’, is outside the progression but plays an important part in underpinning biodiversity. There is also a need to address and manage geodiversity in a given region or specific site to help understand and manage biodiversity.

Looks at the conservation of sites of geological significance. Looks at geoconservation history, ideas, international initiatives, legislation and policy in both an Australian and international perspective

The Pilbara Coast, in NW Australia, stands unique as the most geologically/geomorphologically diverse arid coast globally and, as such, it is a coastline of Global Significance. Ideally, it should have been listed as a site of World Heritage. While there are a variety of coastal forms along the Pilbara Coast, a ubiquitous feature of the region is the development of extensive salt flats landward of mangrove-fringed coastlines, and leeward of barrier limestone ridges and barrier dunes. The aridity of the Pilbara Coast and the occurrence of extensive salt flats lend themselves to exploitation for development of solar salt production ponds but this has resulted in the destruction of unique coastal geomorphology, salt flat habitats, 'sand island ecology' and the natural diagenesis of arid-zone coastal geology. This contribution explores the significance of solar salt pond development along a globally unique coastline, and highlights that there needs to be a component of geoethics in government decision-making that considers all the values of a site.

Definition The physical, biological, and chemical processes operating on the surface and shallow subsurface of a beach, resulting in stratigraphic, granulometric, and sediment compositional variations, construction of physical sedimentary structures and biogenic structures, authigenic/diagenetic mineral responses, and biogenic mineral products.

Definitions Geoheritage. The heritage value assigned to features of a geological nature encompasses globally, nationally, statewide to regionally, and locally significant features of earth science that are intrinsically important or culturally important, offering information or insights into the evolution of the earth or into the history of earth science, or that can be used for research, teaching, or reference (Brocx, 2008). It encompasses the variety of rocks types, stratigraphy, structural geology, geomorphology, and hydrology and covers a large variety of processes and products across a wide range of scales, from global tectonics, mountain building, landscape evolution to local surface processes and products such as weathering, erosion and sedimentation, cliff faces, fossils sites and mineral localities, and, at the microscale, diagenesis and deformation. Geoconservation. This term refers to an action that works toward the preservation of sites of geoheritage significance for heritage, science, or education purposes. It can encompass all important geological features from the regional scale to the individual crystal, involving specific sites (special sites), or ensembles of geological sites. A “specific site” is where a significant geological feature occurs in isolation or may have historical or cultural significance; these have been formally identified in the British Isles as (geological) site(s) of special scientific interest (SSSI) or regionally important geological/geomorphologic sites (RIGS) (Ellis et al., 1996). Geodiversity. Geodiversity is the natural variety of geological, geomorphological, pedological, and hydrological features of a given area and geological processes forming them (Brocx and Semeniuk, 2007). Use of the term, which etymologically means “the diversity of geological features,” should be applied only in a region-specific or site-specific sense, i.e., not as a synonym for geology. Geosite. This is a term used to denote small sites of geoher

Estuaries stand as a distinct environment along the coast in that they bridge the aquatic hydrochemical environmental gap between freshwater and seawater. They can bring another aspect in addition to this hydrochemical setting because the landscape and geomorphic/sedimentologic setting of an estuary provide variability to the “mixing bowl” where freshwater and seawater interact...

Morocco presents a varied and globally important geology reflecting its successive continental-scale geological settings through geological time. Central, Southern and Western Morocco exhibits a rich geological history of crustal, magmatic, tectonic, metamorphic, sedimentary, and palaeontological features from Archaean to Quaternary, from large- to small-scale and varying in significance from international to local. The geostrategic position of Morocco renders it a land where many civilizations met through time leaving archaeological evidence of outstanding values - as such, its geodiversity is even more attractive as is related to historical, archaeological, architectural, cultural and traditional frames which vary with its geology. In this context, we focus on the central Anti-Atlas that consists of numerous Precambrian inliers amongst a matrix? of Palaeozoic strata, and each inlier has the merit to be transformed into thematic geoparks. Zenaga Inlier is a good example of an ensemble of geological features that have a regionally important geological story and geodiversity that can be transformed into a geopark. In this paper, we present geological information on potential geosites in the Zenaga region of the Central Anti-Atlas which could form the bases for future geoparks

There are numerous geological and geomorphic features in King Sound and the tide-dominated delta of the Fitzroy River that are of International to National geoheritage significance. Set in a tropical semiarid climate, the delta of the Fitzroy River has the largest tidal range of any tide-dominated delta in the World. Within King Sound, the Quaternary stratigraphy, comprised of early Holocene gulf-filling mud formed under mangrove cover and followed by middle to late Holocene deltaic sedimentation, and the relationship between Pleistocene linear desert dunes and Holocene tidal flat sediment are globally unique and provide important stratigraphic and climate history models. The principles of erosion, where sheet, cliff and tidal creek erosion combine to develop tidal landscapes and influence (mangrove) ecological responses also provide a unique global classroom for such processes. The high tidal parts of the deltaic system are muddy salt flats with groundwater salinity ranging up to hypersaline. Responding to this, carbonate nodules of various mineralogy are precipitated. Locally, linear sand dunes discharge freshwater into the hypersaline salt flats. With erosion, there is widespread exposure along creek banks and low tidal flats of Holocene and Pleistocene stratigraphy, and development of spits and cheniers in specific portions of the coast.

To further the disciplines of geoheritage and geoconservation, a Geoheritage "tool-kit" has been developed to systematically compile an inventory at various scales of geological and geomorphological features in a given area, assess their levels of significance, and address whether geoheritage features are treated in isolation or as inter-related suites that should be conserved as an ensemble. The Leschenault Peninsula, a retrograding Holocene dune barrier in south-western Australia, and its leeward estuarine lagoon, provide a case study of the application of this tool-kit. The barrier-and-lagoon is unique in Western Australia and comprises a wide variety of geological and geomorphological features, from large to fine scale, and varying in significance from International to State-wide to Regional. Some key features include: active parabolic dunes; an interface between dunes and estuary that is the most complex sedimentologically, hydrologically, and ecologically in Western Australia; a stratigraphy recording a complex Holocene sea level history; barrier retreat marked by parallel bands of submerged beach rock; and a sheet of calcrete above the water table. In terms of geoconservation, addressing the various features of geoheritage value in this area is best achieved by viewing the system as an integrated geopark of interactive processes, geology, and geomorphology.

The Kimberley Coast in north-western Australia is of global geoheritage significance. It is a large-scale ria coast, with a well developed intricate indented rocky shoreline, with local nearshore islands (archipelago), and a distinct suite of coastal sediments. In addition to its intrinsic geoheritage values, its unique geological and geomorphological features are found in an unspoiled wilderness setting in which the ensemble of natural processes are still operating. The Kimberley Coast is cut into Precambrian rocks: the sandstones and basalts of the Kimberley Basin and, in the southern areas, into folded sedimentary rocks and metamorphic rocks of the King Leopold Orogen. The rocks of the region are well exposed along the shore to providing a global classroom by which to study the region's stratigraphy, structure, and lithology. The coastal forms in the Kimberley region have been determined by the structure and lithology of regional geology, interfaces between major geological units, by marine inundation of onshore landforms, and by the sizes, shapes and configuration of rivers, creeks, their tributaries, and other valley tracts in the region. The coast, however, is not just a continuous rocky shore composed of cliffs, and cliffs with benches, as it also has local sediment-filled gulfs and embayments, cliff shores fringed by mangroves, cliff shores with bouldery ribbons in the tidal zone, and stretches of beaches, and in the embayments, muddy tidal flats, spits, cheniers, tidal creeks cut into the tidal flats, and (embayment-head) alluvial fans. Locally, the coast is composed of algal reefs and coral reefs, beach rock, and various types of tempestites. The Kimberley Coast presents several features of geoheritage significance: 1. with ~ 700 km of (simplified) coastal length, it presents the best and most extensive expression of ria morphology in Australia, and also one of the best developed globally; 2. the occurrence of the shore in a monsoonal subhumid/humid tropic

Crystals are very common and, aside from regions of its molten interior, the Earth can be considered to be a crystalline planet with many types of crystals, expressed as thousands of mineral varieties, occurring in diverse environments. Some of these crystals (and minerals) are of geoheritage significance because of their size, composition, shape, zoning, reaction rims, mineral inclusions, fluid and gas inclusions, twinning, dislocations, exsolution, the unusual occurrence or rarity of a crystal attribute, and their form of aggregation, such as desert roses, or druses. If macroscale geological features are assessed as important in unravelling Earth history, and afforded geoheritage significance, then importance should also be given to crystals where similar principles and patterns are present. Some notable crystals of geoheritage significance are the giant gypsum in Mexico and in Spain, the zircon crystals of Jack Hills (the oldest crystals on Earth), the large well-formed pyrite in Spain, snowball garnets from various locations, and Iceland spar from its type locality.

Identifying sites of coastal geoheritage significance begins with classification of coastal geology and geomorphology. However, classifying coasts for purposes of geoheritage is made difficult due to the complexity, intergradation, and different scales at which coastal features are expressed, with variation potentially present locally or regionally. Also, geoheritage must address geological content as well as coastal geomorphology expressed erosionally and/or sedimentologically, and Earth history as manifested in coastal erosional and stratigraphic products. While geological and environmental settings play important roles in determining regional variation in coastal form and coastal products, or expression of geological content, coasts at the local scale commonly are expressions of one or more of the main processes of (marine) inundation, erosion, and deposition, and/or of subdominant processes of biogenic activity and diagenesis. To address this coastal geodiversity for geoheritage and geoconservation in Western Australia, a three-level scalar hierarchical approach is used. Level 1 identifies the regional geological and environmental setting, i.e., recognising major cratons and basins, and the climatic/oceanographic setting of a coast, which determine regional coastal forms. Level 2 identifies the main coastal types developed by coastforming processes (e.g., marine inundation of pre-existing landforms; coastal erosion; exhuming of older landforms; construction by Holocene sedimentation, coasts formed biogenically, amongst others), as well as coastal types that illustrate Holocene history geomorphically or stratigraphically, or manifest pre-Holocene rock sequences in sea cliffs. Level 3 identifies finer-scale characteristics particular to any coast within its regional setting to develop an inventory of features providing data within the context of the coastal types for comparative geoconservation purposes. All three levels need to be applied to fully categorise coas

The coast is one of the most complex environments on the Earth’s surface, being a zone of intersection and interaction of land, sea, groundwater, and atmosphere and the processes therein, and carries processes and products that are either not present or only weakly developed elsewhere. With other matters such as lithology, structure, or geological framework being equal, the coastal zone is one that generally results in greater geodiversity than elsewhere. The range of interacting physical, chemical and biological processes in the coastal zone include: waves, tides, storms, and cyclonic activity (all resulting in erosion, sediment mobility, particle size sorting, sedimentary structures); development of a splash zone; onshore winds resulting in shore-directed wind waves and longshore drift, and in erosion, transport, particle sorting, lag deposits, and dune building; sedimentation mediated physically by fluvial influx, longshore and/or onshore transport, and tidal currents, or biologically by skeletal production; bioerosion; chemical erosion; salt weathering; tidal invasion of coastal sedimentary bodies by seawater; evaporation and transpiration; hydrochemical effects such as solution, or precipitation of carbonates, gypsum, or halite; fresh-water seepage and its effect on ecology and coastal erosion; sediment delivery fluvially; and biological effects including skeletal production, encrustation, biostrome and bioherm building, grain fragmentation, and bioturbation. A significant factor also is the prevailing nature of many of the processes therein. Coasts commonly exhibit shore-normal environmental gradients and hence a graded expression of processes, resulting in variation in complexity and geodiversity in physical, geochemical and biological products across the shore, and variation in fine- to small-scale stratigraphic sequences. To provide a perspective of the expression of any geodiversity of bedrock, and of the diversity and complexity of sedimentary systems in

Geoheritage and geoconservation are concerned with the preservation of Earth Science features, and are important endeavours globally, as reflected in various international and intra-national bodies set up for conservation, with agreements, conventions, and inter-governmental initiatives. Historically, the United Kingdom is considered the birthplace of the discipline of Geology, and with its history and its leadership role in the preservation of geological sites, it is also the birthplace of geoheritage and geoconservation; both endeavours are integral components of education, tourism, planning and environmental management. In addition, in Pan-Europe, and globally under the World Heritage Convention, inventory-based geoconservation has been adopted as a whole-of-government approach. Australia presents an internationally contrasting, and a nationally internally diverse history in the arena of geoconservation. Western Australia, for instance, generally lags the world trend in practicing geoconservation, while Tasmania is a leader in the arena of geoconservation. For this reason, an objective of this paper is to raise the consciousness of Western Australian scientists, planners, and land managers, who are outside the field of geology, to the issues of geoheritage and geoconservation. Geoheritage encompasses global, national, state-wide, and local features of geology, at all scales that are intrinsically important sites or culturally important sites offering information or insights into the evolution of the Earth; or into the history of science, or that can be used for research, teaching, or reference. As geoheritage focuses on features that are geological, the scope and scale of what constitutes Geology, such as its igneous, metamorphic, sedimentary, stratigraphic, structural, geochemical, palaeontologic, geomorphic, pedologic, and hydrologic attributes, needs to be defined - from there, all that is encompassed by this discipline will be involved in geoheritage, and pot