b'AEGC 2023Short abstractsfeature to the east of the Gidyea Structure represents the uppercomparison to other sedimentary basins of a similar age in crustal expression of the CCA. Queensland, the Galilee Basin remains relatively under explored. This paper takes an in-depth look at a single land release for Postulated sources of the CCA are enhanced fluid flow andpetroleum exploration in the Galilee Basin made in 2008. In the alteration proximal to the Gidyea Structure, or metamorphismshort term, this led to a flurry of activity across the basin, but of Paleoproterozoic carbonaceous deep-water sedimentsin the longer term most of the awarded tenures have ceased preserved proximal to the Gidyea Structure. The subsequentto exist. This raises the question of how we might measure the inversion and metamorphism of these basins have generated asuccess of a land release. Is it by the number of applicants eager suite of linear and pipe-like conductive features adjacent to theto secure acreage, or is it by the long-term success of those Gidyea Structure zone which extends to mid-crustal levels but isapplicants? And how should we account for the unforeseen also coincident with known graphitic metasediments. impact of oil price changes, regulatory uncertainty and poor social licence in assessing those tenures, and ultimately the Gravity modelling of crooked line traverses to constrainsuccess of the land release?Southeast Lachlan Crustal Transect 2 D seismicThis paper will review how each tenderer, along with the few reflection interpretations in the Australian Alps existing tenure holders already operating in the basin when the land release was made, have fared through the lens of the Phil Skladzien, Ross Cayley, Suzanne Haydon and Cameronbigger picture issues that have arisen since that land release, Cairns and what that has meant for exploration in the Galilee Basin.Geological Survey of VictoriaThe Southeast Lachlan Crustal Transect (SLaCT) is a 629 km routeMarked depositional and organic facies change across across the geology of northeast Victoria and southeast New Souththe Paleocene-Eocene in the Gippsland Basin, Australia.Wales in southeast Australia. SLaCT is a collaborative applied geoscience research project between the Geological Survey ofGregory Smith 1 Simon Lang2, Adam Charles3, Simon Horan4 Victoria (GSV), Geoscience Australia (GA), Geological Survey ofand Nick Hoffman4New South Wales (GSNSW) and AuScope Limited (AuScope). 1 Curtin University Two-dimensional deep crustal reflection seismic and detailed2 University of Western Australia ground gravity surveys were acquired along three transects3 MGPalaeo crossing the Australian Alps to investigate the 3D geometry4 CarbonNetof the fundamental geological building blocks of southeastSignificant organic facies change occurred in the Latrobe Group Australia and address research questions that inform on mineralfrom the Late Paleocene to Late Eocene in the Gippsland Basin, prospectivity and geological hazard assessments for this region.controlled by climate, basin tectonics and sedimentary facies. Access limitations due to extreme terrain confined the SLaCTThis transition from PaleoceneEarly Eocene progradational-route to tracks navigable by vibroseis trucks. This dictated thataggradational low stand tracts to MiddleLate Eocene large portions of the seismic transects (and new detailed gravitywestward backstepping transgressive systems tracts is traverses) were acquired with crooked line geometries. documented by integrated sedimentary, palynology and Modelling of gravity data along seismic transects is a useful wayorganic petrology studies of recent extensive coring tied to constrain, test and refine seismic interpretations. A workflowto high quality seismic. The Palaeocene and Early Eocene of iterative seismic interpretation refinements informed by, andinshore area was dominated by alluvial plain/upper delta plain integrated with, profile gravity modelling results constrainedfacies, 50-70km behind the barrier system further east near by mapped geology has been applied. This approach producesNannygai-Luderick. Rapid transgression by the middle Eocene a mutually viable interpretation of the crustal architecture, fartransformed the area into coastal plain/marginal marine facies more robust than just seismic data interpreted in isolation.behind a barrier system moved near Barracouta, with the barrier The models presented here are constrained by all availablesystem moving further west into the onshore area by Late existing petrophysical data, geological mapping and models,Eocene.geophysical datasets, and geoscientific interpretations. The organic-rich facies in PaleoceneEarly Eocene upper delta plain facies mainly developed in abandoned channels The high degree of line crookedness presented challenges foror between channel belts in back-levee swamps and are thin, the 21/2-D forward modelling of gravity profile data alongdiscontinuous and prone to splitting due to channel switching the traverses. Several methods were applied to mitigate theand avulsion splays. The coals are durains (dull) with high distortion effects of line crookedness in the forward modellingtelovitrinite:detrovitrinite (dominated by trees), with gelified process, aiming to provide the closest integration betweendetrovitrinite groundmass, high inertinite from seasonal wet-seismic interpretations and gravity models and to account fordry conditions, and low pyrite with low source rock potential.the influence of variably proximal off-line geology resulting from line crookedness, and inconsistently affecting the gravityThe middlelate Eocene organic facies include thick response along the meandering traverses. ombrogenous peats best developed in the lower coastal plains during the late transgressive/aggradational/early regressive phases. They comprise upward drying vitrainclarain Anatomy of a land release. lithotypes with moderate telovitrinite:detrovitrinite and Sue Slater increasing perhydrous liptinite, developed in extensive peat swamps adjacent to but isolated from the main distributary Historically the Galilee Basin has been explored for bothchannel belts. The more distal back-barrier marshes form conventional petroleum and coal seam gas, however, inthinner clarain and cannel peats that build out over the FEBRUARY 2023 PREVIEW 140'