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Journal articles on the topic 'Lachlan'

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Published: 4 June 2021

Last updated: 29 January 2023

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1

Glen, R. A., and J. L. Walshe. "Cross‐structures in the Lachlan Orogen: The Lachlan Transverse Zone example." Australian Journal of Earth Sciences 46, no. 4 (August 1999): 641–58. http://dx.doi.org/10.1046/j.1440-0952.1999.00734.x.

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2

Parsons, T. G., and John Ritchie. "Lachlan Macquarie. A Biography." Labour History, no. 54 (1988): 125. http://dx.doi.org/10.2307/27504445.

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3

Tierney, Robert, and Kevin Parton. "'From These Youth Has Gone': Population Decline in the Lachlan Region of New South Wales, 1920-1947." Local Population Studies, no. 95 (December 31, 2015): 50–68. http://dx.doi.org/10.35488/lps95.2015.50.

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This article analyses major events during the 1920s, 1930s, and 1940s affecting the Lachlan region, in New South Wales, in order to assess their relative impact on population change. The analysis juxtaposes the demographic changes taking place against the economic context of the time. The Lachlan region is compared with the four other wheatsheep regions of New South Wales and with the State generally. The paper demonstrates that population decline in the Lachlan region in the 1930s and 1940s was substantially greater than that of other wheat-sheep regions and of the State of New South Wales generally, and sets out to explain this anomaly. The Depression, the Second World War, drought over a sequence of years, and changing technology are shown, in combination, to be the underlying causes of substantial change that heralded the long-term drift of population from regional and rural NSW; especially so in the Lachlan region.

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4

Pillay, Anand, and Mark D. Schlatter. "Some results on permutation group isomorphism and categoricity." Journal of Symbolic Logic 67, no. 3 (September 2002): 910–14. http://dx.doi.org/10.2178/jsl/1190150138.

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AbstractWe extend Morley's Theorem to show that if a theory is κ-p-categorical for some uncountable cardinal κ, it is uncountably categorical. We then discuss ω-p-categoricity and provide examples to show that similar extensions for the Baldwin-Lachlan and Lachlan Theorems are not possible.

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5

Collins, William J., Hui-Qing Huang, Peter Bowden, and A. I. S. Kemp. "Repeated S–I–A-type granite trilogy in the Lachlan Orogen and geochemical contrasts with A-type granites in Nigeria: implications for petrogenesis and tectonic discrimination." Geological Society, London, Special Publications 491, no. 1 (May 3, 2019): 53–76. http://dx.doi.org/10.1144/sp491-2018-159.

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AbstractThe classical S–I–A-type granites from the Lachlan Orogen, SE Australia, formed as a tectonic end-member of the accretionary orogenic spectrum, the Paleozoic Tasmanides. The sequence of S- to I- to A-type granite is repeated at least three times. All the granites are syn-extensional, formed in a dominantly back-arc setting behind a single, stepwise-retreating arc system between 530 and 230 Ma. Peralkaline granites are rare. Systematic S–I–A progressions indicate the progressive dilution of an old crustal component as magmatism evolved from arc (S-type) to proximal back-arc (I-type) to distal back-arc (A-type) magmatism. The alkaline and peralkaline A-type Younger granites of Nigeria were generally hotter and drier than the Lachlan A-type granites and were emplaced into an anhydrous Precambrian basement during intermittent intracontinental rifting. This geodynamic environment contrasts with the distal back-arc setting of the Lachlan A-type granites, where magmatism migrated rapidly across the orogen. Tectonic discrimination diagrams are inappropriate for the Lachlan granites, placing them in the wrong settings. Only the peralkaline Narraburra suite of the Lachlan Orogen fits the genuine ‘within-plate’ setting of the Nigerian A-type granites. Such discrimination diagrams require re-evaluation in the light of an improved modern understanding of tectonic processes, particularly the role of extensional tectonism and its geodynamic drivers.

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6

Lempp, Steffen, and Sui Yuefei. "An extended Lachlan splitting theorem." Annals of Pure and Applied Logic 79, no. 1 (May 1996): 53–59. http://dx.doi.org/10.1016/0168-0072(95)00039-9.

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7

Douglas, J., A. Tindley, and A. Smyth. "Dr Lachlan Grant (1871-1945)." Occupational Medicine 64, no. 4 (May 20, 2014): 233–34. http://dx.doi.org/10.1093/occmed/kqu070.

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8

Findlay, Merrill. "Kate Kelly on the Lachlan." Rural Society 21, no. 2 (February 2012): 136–45. http://dx.doi.org/10.5172/rsj.2012.21.2.136.

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9

Scarlett, Nicola, Jeremy Karl Cockcroft, and Ian Swainson. "Lachlan M. D. Cranswick (1968–2010)." Journal of Applied Crystallography 43, no. 5 (September 10, 2010): 1134. http://dx.doi.org/10.1107/s0021889810035971.

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10

SPAGGIARI, C. V., D. R. GRAY, and D. A. FOSTER. "Lachlan Orogen subduction-accretion systematics revisited." Australian Journal of Earth Sciences 51, no. 4 (August 2004): 549–53. http://dx.doi.org/10.1111/j.1400-0952.2004.01073.x.

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11

Guzmán Romero, Jorge Adrián. "Deberes climáticos de todos, deberes climáticos de nadie." Revista de El Colegio de San Luis 12, no. 23 (September 27, 2022): 1–9. http://dx.doi.org/10.21696/rcsl122320221447.

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12

Morris, John. "Lachlan Neil Gollan, AM, KStJ, MB BS." Medical Journal of Australia 169, no. 6 (September 1998): 333. http://dx.doi.org/10.5694/j.1326-5377.1998.tb140289.x.

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13

Skorobogatykh, Natalya. "Governor Lachlan Macquarie – Builder of British Australia." South East Asia Actual problems of Development, no. 3 (52) (2021): 254–68. http://dx.doi.org/10.31696/2072-8271-2021-3-3-52-254-268.

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The article is devoted to the activities of one of the most prominent administrators in the history of Australia during the colonial period – Lachlan Macquarie. He not only managed to establish the firm order in the territories entrusted to him and significantly expand the zone of British settlements in the southeast of the continent, but also laid the foundations for the introduction the system of self-government here.

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14

Moore, C. "Review of Lachlan Strahan’s Day of Reckoning." History Australia 3, no. 1 (January 2006): 21.1–21.2. http://dx.doi.org/10.2104/ha060021.

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15

Glen, R. A. "Palaeomagnetism and Terranes in the Lachlan Orogen." Exploration Geophysics 24, no. 2 (June 1993): 247–55. http://dx.doi.org/10.1071/eg993247.

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16

Powell, C. McA, J. P. Cole, and T. J. Cudahy. "Megakinking in the Lachlan Fold Belt, Australia." Journal of Structural Geology 7, no. 3-4 (January 1985): 281–300. http://dx.doi.org/10.1016/0191-8141(85)90036-7.

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17

Cooper, S. Barry, Angsheng Li, and Xiaoding Yi. "On the distribution of Lachlan nonsplitting bases." Archive for Mathematical Logic 41, no. 5 (July 1, 2002): 455–82. http://dx.doi.org/10.1007/s001530100095.

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18

Podzorov, S. Yu. "On the definition of a Lachlan semilattice." Siberian Mathematical Journal 47, no. 2 (March 2006): 315–23. http://dx.doi.org/10.1007/s11202-006-0045-2.

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19

Gray, D. R., D. A. Foster, and F. P. Bierlein. "Geodynamics and metallogeny of the Lachlan Orogen." Australian Journal of Earth Sciences 49, no. 6 (December 2002): 1041–56. http://dx.doi.org/10.1046/j.1440-0952.2002.00962.x.

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20

Costelloe, Ross, Tanya Fomin, Ross Cayley, Cameron Cairns, and Tim Rawling. "2018 Southeast Lachlan Seismic Survey: New Heights." ASEG Extended Abstracts 2019, no. 1 (November 11, 2019): 1–4. http://dx.doi.org/10.1080/22020586.2019.12073154.

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21

Hammond, John Todd. "Nonisomorphism of lattices of recursively enumerable sets." Journal of Symbolic Logic 58, no. 4 (December 1993): 1177–88. http://dx.doi.org/10.2307/2275136.

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Let ω be the set of natural numbers, let be the lattice of recursively enumerable subsets of ω, and let A be the lattice of subsets of ω which are recursively enumerable in A. If U, V ⊆ ω, put U =* V if the symmetric difference of U and V is finite.A natural and interesting question is then to discover what the relation is between the Turing degree of A and the isomorphism class of A. The first result of this form was by Lachlan, who proved [6] that there is a set A ⊆ ω such that A ≇ . He did this by finding a set A ⊆ ω and a set C ϵ A such that the structure ({W ϵ A∣W ⊇ C},∪,∩)/=* is a Boolean algebra and is not isomorphic to the structure ({W ϵ ∣W ⊇ D},∪,∩)/=* for any D ϵ . There is a nonrecursive ordinal which is recursive in the set A which he constructs, so his set A is not (see, for example, Shoenfield [11] for a definition of what it means for a set A ⊆ ω to be ). Feiner then improved this result substantially by proving [1] that for any B ⊆ ω, B′ ≇ B, where B′ is the Turing jump of B. To do this, he showed that for each X ⊆= ω there is a Boolean algebra which is but not and then applied a theorem of Lachlan [6] (definitions of and Boolean algebras will be given in §2). Feiner's result is of particular interest for the case B = ⊘, for it shows that the set A of Lachlan can actually be chosen to be arithmetical (in fact, ⊘′), answering a question that Lachlan posed in his paper. Little else has been known.

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22

Moran, Nicholas P., George G. Ganf, Todd A. Wallace, and Justin D. Brookes. "Flow variability and longitudinal characteristics of organic carbon in the Lachlan River, Australia." Marine and Freshwater Research 65, no. 1 (2014): 50. http://dx.doi.org/10.1071/mf12297.

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Heterotrophic organic-carbon cycling is a major source of energy to aquatic food webs, yet there are few studies into patterns of heterotrophic productivity in large lowland rivers. The Lachlan River experienced a period of extreme flow variability from September 2010 to February 2011; for example, daily discharge (ML day–1) at one site reached >22 times its 10-year average. Heterotrophic cycling of dissolved organic carbon (DOC) and particulate organic carbon (POC) were assessed over this period at six sites on the Lachlan River. Concentrations of total organic carbon (TOC) ranged from 7 to 30 mg L–1, of which the majority was in dissolved form. Concentration of DOC was positively correlated with daily discharge. Biochemical oxygen demand of TOC over 5 days (BOD5) showed significant variability, ranging from 0.6 to 6.6 mg O2 L–1. BOD5 did not appear related to discharge, but instead to a range of other factors, including regulation via weirs, lateral and longitudinal factors. Partitioning of DOC and POC showed that POC had an influence on BOD5 comparable to DOC. This is relevant to environmental-flow management in the Lachlan River, the Murray–Darling Basin and rivers generally, by showing that flow variability influences a fundamental ecosystem characteristic, namely organic carbon.

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23

Bort, Eberhard. "The Life and Times of Dr Lachlan Grant." Scottish Affairs 26, no. 3 (August 2017): 342–45. http://dx.doi.org/10.3366/scot.2017.0194.

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24

Spaggiari, Catherine V., David R. Gray, and David A. Foster. "Ophiolite accretion in the Lachlan Orogen, Southeastern Australia." Journal of Structural Geology 26, no. 1 (January 2004): 87–112. http://dx.doi.org/10.1016/s0191-8141(03)00084-1.

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25

VandenBerg, A. H. M. "Timing of orogenic events in the Lachlan Orogen." Australian Journal of Earth Sciences 46, no. 5 (October 1999): 691–701. http://dx.doi.org/10.1046/j.1440-0952.1999.00738.x.

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26

Haydon, Suzanne. "Geological Survey of Victoria: Southeast Lachlan Crustal Transect." Preview 2019, no. 202 (September 3, 2019): 19–20. http://dx.doi.org/10.1080/14432471.2019.1672259.

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27

Glen, R. A., S. Meffre, and R. J. Scott. "Benambran Orogeny in the Eastern Lachlan Orogen, Australia." Australian Journal of Earth Sciences 54, no. 2-3 (March 2007): 385–415. http://dx.doi.org/10.1080/08120090601147019.

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28

Podzorov, S. Yu. "The universal Lachlan semilattice without the greatest element." Algebra and Logic 46, no. 3 (May 2007): 163–87. http://dx.doi.org/10.1007/s10469-007-0016-0.

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29

Glen, R. A., and D. Wyborn. "Inferred thrust imbrication, deformation gradients and the Lachlan Transverse Zone in the Eastern Belt of the Lachlan Orogen, New South Wales." Australian Journal of Earth Sciences 44, no. 1 (February 1, 1997): 49–68. http://dx.doi.org/10.1080/08120099708728293.

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30

Downey, R. G., and L. V. Welch. "Splitting properties of r.e. sets and degrees." Journal of Symbolic Logic 51, no. 1 (March 1986): 88–109. http://dx.doi.org/10.2307/2273946.

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A pair of r.e. sets A1, A2 are said to split an r.e. set A (written A1 Δ A2 = A) if A1 ∩ A2 = ∅ and A1 ∪ A2 = A. In the literature there are various results asserting certain splitting properties hold for all r.e. sets. For example Sacks' splitting theorem (cf. [So]) asserts that an r.e. nonrecursive set A may be split into a pair of Turing incomparable r.e. sets A1, A2, and Lachlan's splitting theorem [La5] asserts that A may be split into a pair of r.e. sets A1, A2 for which there exists an r.e. set B with B ⊕ A1, B ⊕ A2 <TA and with the infinum of the Turing degrees of B ⊕ A1 and B ⊕ A2 existing in the upper semilattice of r.e. degrees.Two of the earliest observations establishing that splitting properties possessed by some r.e. sets are not possessed by others, are Lachlan's nondiamond theorem [La1] (and so, in particular, no complete r.e. set can be split nontrivially with degree theoretic inf 0) and the Yates-Lachlan construction of a minimal pair (a pair of nonzero r.e. degrees with inf 0). Other examples of this phenomenon, which are not obtained by interpreting degree theoretic results in the r.e. sets, are Lachlan's construction of nonmitotic r.e. sets [La2] (sets which cannot be split into a pair of r.e. sets of the same degree) and, later, Ladner's [Ld1, 2] and Ingrassia's [In] analysis of their degrees.

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31

Chappell, B. W. "Compositional variation within granite suites of the Lachlan Fold Belt: its causes and implications for the physical state of granite magma." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 87, no. 1-2 (1996): 159–70. http://dx.doi.org/10.1017/s026359330000657x.

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ABSTRACT:Granites within suites share compositional properties that reflect features of their source rocks. Variation within suites results dominantly from crystal fractionation, either of restite crystals entrained from the source, or by the fractional crystallisation of precipitated crystals. At least in the Lachlan Fold Belt, the processes of magma mixing, assimilation or hydrothermal alteration were insignificant in producing the major compositional variations within suites. Fractional crystallisation produced the complete variation in only one significant group of rocks of that area, the relatively high temperature Boggy Plain Supersuite. Modelling of Sr, Ba and Rb variations in the I-type Glenbog and Moruya suites and the S-type Bullenbalong Suite shows that variation within those suites cannot be the result of fractional crystallisation, but can be readily accounted for by restite fractionation. Direct evidence for the dominance of restite fractionation includes the close chemical equivalence of some plutonic and volcanic rocks, the presence of plagioclase cores that were not derived from a mingled mafic component, and the occurrence of older cores in many zircon crystals. In the Lachlan Fold Belt, granite suites typically evolved through a protracted phase of restite fractionation, with a brief episode of fractional crystallisation sometimes evident in the most felsic rocks. Evolution of the S-type Koetong Suite passed at about 69% SiO2 from a stage dominated by restite separation to one of fractional crystallisation. Other suites exist where felsic rocks evolved in the same way, but the more mafic rocks are absent. In terranes in which tonalitic rocks formed at high temperatures are more common, fractional crystallisation would be a more important process than was the case for the Lachlan Fold Belt.

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32

Glen, R. A. "Thrusts and thrust-associated mineralization in the Lachlan Orogen." Economic Geology 90, no. 6 (October 1, 1995): 1402–29. http://dx.doi.org/10.2113/gsecongeo.90.6.1402.

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33

Morand, Vincent J., and Stafford McKnight. "Metamorphic style of the Tabberabbera Zone, Lachlan Fold Belt." ASEG Extended Abstracts 2006, no. 1 (December 2006): 1–5. http://dx.doi.org/10.1071/aseg2006ab118.

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34

Bierlein, Frank P., David R. Gray, and David A. Foster. "Metallogenic relationships to tectonic evolution – the Lachlan Orogen, Australia." Earth and Planetary Science Letters 202, no. 1 (August 2002): 1–13. http://dx.doi.org/10.1016/s0012-821x(02)00757-4.

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35

Fergusson, Christopher L., David R. Gray, and Ray A. F. Cas. "Overthrust terranes in the Lachlan fold belt, southeastern Australia." Geology 14, no. 6 (1986): 519. http://dx.doi.org/10.1130/0091-7613(1986)14<519:otitlf>2.0.co;2.

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36

Bierlein, Frank P., and Andy R. Wilde. "Preface: Tectonics to mineral discovery—deconstructing the Lachlan Orogen." Mineralium Deposita 42, no. 5 (April 11, 2007): 433–34. http://dx.doi.org/10.1007/s00126-007-0136-4.

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37

Willman, C. E., A. H. M. VandenBerg, and V. J. Morand. "Evolution of the southeastern Lachlan Fold Belt in Victoria." Australian Journal of Earth Sciences 49, no. 2 (April 2002): 271–89. http://dx.doi.org/10.1046/j.1440-0952.2002.00914.x.

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38

Schaap, Thomas A., Sebastien Meffre, Joanne M. Whitakker, Matthew J. Cracknell, and Michael Roach. "Modelling the Palaeozoic tectonic evolution of the Lachlan Orogen." ASEG Extended Abstracts 2019, no. 1 (November 11, 2019): 1–5. http://dx.doi.org/10.1080/22020586.2019.12073123.

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39

Collins, W. J. "Lachlan Fold Belt granitoids: products of three-component mixing." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 87, no. 1-2 (1996): 171–81. http://dx.doi.org/10.1017/s0263593300006581.

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ABSTRACT:The paradox of Lachlan Fold Belt (LFB) granitoids is that although contrasted chemical types (S- and I-types) imply melting of distinct crustal sources, the simple Nd–Sr–Pb–O isotopic arrays indicate a continuum, suggesting mixing of magmatic components. The paradox is resolved by the recognition that the previously inferred, isotopically primitive end-member is itself a crust-mantle mix, so that three general source components, mantle, lower crust and middle crust, comprise the granitoids. Based on Nd isotopic evidence, mantle-derived basaltic magmas melted and mixed with Neoproterozoic-Cambrian, arc-backarc-type material to produce primitive I-type, parental granitoid magmas in the lower–middle crust. Ordovician metasediment, locally underthrust to mid-crustal levels, was remobilised under the elevated geotherms and is most clearly recognised as diatexite in the Cooma complex, but it also exists as gneissic enclaves in S-type granites. The diatexite mixed with the hybrid I-type magmas to produce the parental S-type magmas. Unique parent magma compositions of individual granite suites reflect variations within any or all of the three major source components, or between the mixing proportions. For example, chemical tie-lines between Cooma diatexite and mafic I-type Jindabyne suite magma encompass almost all mafic S-type granites of the vast Bullenbalong supersuite, consistently in the proportion Jindabyne: Cooma, 30:70. The modelling shows that LFB S-type magmas are heavily contaminated I-type magmas, produced by large-scale mixing of hot I-type material with lower temperature diatexite in the middle crust. The model implies a genetic link between migmatite and pluton-scale, crustally derived (S-type) granites.Given the chemical and isotopic contrasts of the crustally derived source components, and their typically unequal proportions in the magmas, it is not surprising that the LFB granitoids are so distinctive and have been categorised as S- and I-type. The sublinear chemical trends of the granitoid suites are considered to be secondary effects associated with crystal fractionation of unique parental magmas that were formed by three-component mixing. The model obviates the necessity for multiple underplating events and Proterozoic continental basement, in accordance with the observed tectonostratigraphy of the Lachlan Fold Belt.

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40

Jones, B. G., C. L. Fergusson, and P. F. Zambelli. "Ordovician contourites in the Lachlan Fold Belt, eastern Australia." Sedimentary Geology 82, no. 1-4 (January 1993): 257–70. http://dx.doi.org/10.1016/0037-0738(93)90125-o.

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41

Mortimer, N., J. M. Palin, W. J. Dunlap, and F. Hauff. "Extent of the Ross Orogen in Antarctica: new data from DSDP 270 and Iselin Bank." Antarctic Science 23, no. 3 (February 8, 2011): 297–306. http://dx.doi.org/10.1017/s0954102010000969.

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AbstractThe Ross Sea is bordered by the Late Precambrian–Cambrian Ross–Delamerian Orogen of East Antarctica and the more Pacific-ward Ordovician–Silurian Lachlan–Tuhua–Robertson Bay–Swanson Orogen. A calcsilicate gneiss from Deep Sea Drilling Project 270 drill hole in the central Ross Sea, Antarctica, gives a U-Pb titanite age of 437 ± 6 Ma (2σ). This age of high-grade metamorphism is too young for typical Ross Orogen. Based on this age, and on lithology, we propose a provisional correlation with the Early Palaeozoic Lachlan–Tuhua–Robertson Bay–Swanson Orogen, and possibly the Bowers Terrane of northern Victoria Land. A metamorphosed porphyritic rhyolite dredged from the Iselin Bank, northern Ross Sea, gives a U-Pb zircon age of 545 ± 32 Ma (2σ). The U-Pb age, petrochemistry, Ar-Ar K-feldspar dating, and Sr and Nd isotopic ratios indicate a correlation with Late Proterozoic–Cambrian igneous protoliths of the Ross Orogen. If the Iselin Bank rhyolite is not ice-rafted debris, then it represents a further intriguing occurrence of Ross basement found outside the main Ross–Delamerian Orogen.

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42

Wilkins, Colin, and Mike Quayle. "Structural Control of High-Grade Gold Shoots at the Reward Mine, Hill End, New South Wales, Australia." Economic Geology 116, no. 4 (June 1, 2021): 909–35. http://dx.doi.org/10.5382/econgeo.4807.

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Abstract The Reward mine at Hill End hosts structurally controlled orogenic gold mineralization in moderately S plunging, high-grade gold shoots located at the intersection between a late, steeply W dipping reverse fault zone and E-dipping, bedding-parallel, laminated quartz veins (the Paxton’s vein system). The mineralized bedding-parallel veins are contained within the middle Silurian to Middle Devonian age, turbidite-dominated Hill End trough forming part of the Lachlan orogen in New South Wales. The Hill End trough was deformed in the Middle Devonian (Tabberabberan orogeny), forming tight, N-S–trending, macroscopic D2 folds (Hill End anticline) with S2 slaty cleavage and associated bedding-parallel veins. Structural analysis indicates that the D2 flexural-slip folding mechanism formed bedding-parallel movement zones that contained flexural-slip duplexes, bedding-parallel veins, and saddle reefs in the fold hinges. Bedding-parallel veins are concentrated in weak, narrow shale beds between competent sandstones with dip angles up to 70° indicating that the flexural slip along bedding occurred on unfavorably oriented planes until fold lockup. Gold was precipitated during folding, with fluid-flow concentrated along bedding, as fold limbs rotated, and hosted by bedding-parallel veins and associated structures. However, the gold is sporadically developed, often with subeconomic grades, and is associated with quartz, muscovite, chlorite, carbonates, pyrrhotite, and pyrite. East-west shortening of the Hill End trough resumed during the Late Devonian to early Carboniferous (Kanimblan orogeny), producing a series of steeply W dipping reverse faults that crosscut the eastern limb of the Hill End anticline. Where W-dipping reverse faults intersected major E-dipping bedding-parallel veins, gold (now associated with galena and sphalerite) was precipitated in a network of brittle fractures contained within the veins, forming moderately S plunging, high-grade gold shoots. Only where major bedding-parallel veins were intersected, displaced, and fractured by late W-dipping reverse faults is there a potential for localization of high-grade gold shoots (>10 g/t). A revised structural history for the Hill End area not only explains the location of gold shoots in the Reward mine but allows previous geochemical, dating, and isotope studies to be better understood, with the discordant W-dipping reverse faults likely acting as feeder structures introducing gold-bearing fluids sourced within deeply buried Ordovician volcanic units below the Hill End trough. A comparison is made between gold mineralization, structural style, and timing at Hill End in the eastern Lachlan orogen with the gold deposits of Victoria, in the western Lachlan orogen. Structural styles are similar where gold mineralization is formed during folding and reverse faulting during periods of regional east-west shortening. However, at Hill End, flexural-slip folding-related weakly mineralized bedding-parallel veins are reactivated to a lesser degree once folds lock up (cf. the Bendigo zone deposits in Victoria) due to the earlier effects of fold-related flattening and boudinage. The second stage of gold mineralization was formed by an array of crosscutting, steeply W dipping reverse faults fracturing preexisting bedding-parallel veins that developed high-grade gold shoots. Deformation and gold mineralization in the western Lachlan orogen started in the Late Ordovician to middle Silurian Benambran orogeny and continued with more deposits forming in the Bindian (Early Devonian) and Tabberabberan (late Early-Middle Devonian) orogenies. This differs from the Hill End trough in the eastern Lachlan orogen, where deformation and mineralization started in the Tabberabberan orogeny and culminated with the formation of high-grade gold shoots at Hill End during renewed compression in the early Carboniferous Kanimblan orogeny.

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Gray, D. R., and D. A. Foster. "Orogenic concepts; application and definition; Lachlan fold belt, eastern Australia." American Journal of Science 297, no. 9 (November 1, 1997): 859–91. http://dx.doi.org/10.2475/ajs.297.9.859.

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Morris, John C. H. "John Lachlan Gollan MB BS, MD, PhD, FRACP, FRCP, FACP." Medical Journal of Australia 202, no. 11 (June 2015): 599. http://dx.doi.org/10.5694/mja15.00209.

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Murphy, N. C., and D. R. Gray. "East‐directed overthrusting in the Melbourne Zone, Lachlan Fold Belt." Australian Journal of Earth Sciences 39, no. 1 (February 1992): 37–53. http://dx.doi.org/10.1080/08120099208727999.

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Page, Anthony. "Enlightenment, Empire and Lachlan Macquarie’s Journey Through Persia and Russia." History Australia 6, no. 3 (January 2009): 70.1–70.15. http://dx.doi.org/10.2104/ha090070.

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47

Spaggiari, C. V., D. R. Gray, D. A. Foster, and C. M. Fanning. "Occurrence and significance of blueschist in the southern Lachlan Orogen." Australian Journal of Earth Sciences 49, no. 2 (April 2002): 255–69. http://dx.doi.org/10.1046/j.1440-0952.2002.00915.x.

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Chappell, B. W., and A. J. R. White. "I- and S-type granites in the Lachlan Fold Belt." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 83, no. 1-2 (1992): 1–26. http://dx.doi.org/10.1017/s0263593300007720.

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ABSTRACTGranites and related volcanic rocks of the Lachlan Fold Belt can be grouped into suites using chemical and petrographic data. The distinctive characteristics of suites reflect source-rock features. The first-order subdivision within the suites is between those derived from igneous and from sedimentary source rocks, the I- and S-types. Differences between the two types of source rocks and their derived granites are due to the sedimentary source material having been previously weathered at the Earth's surface. Chemically, the S-type granites are lower in Na, Ca, Sr and Fe3+/Fe2+, and higher in Cr and Ni. As a consequence, the S-types are always peraluminous and contain Al-rich minerals. A little over 50% of the I-type granites are metaluminous and these more mafic rocks contain hornblende. In the absence of associated mafic rocks, the more felsic and slightly peraluminous I-type granites may be difficult to distinguish from felsic S-type granites. This overlap in composition is to be expected and results from the restricted chemical composition of the lowest temperature felsic melts. The compositions of more mafic I- and S-type granites diverge, as a result of the incorporation of more mafic components from the source, either as restite or a component of higher temperature melt. There is no overlap in composition between the most mafic I- and S-type granites, whose compositions are closest to those of their respective source rocks. Likewise, the enclaves present in the more mafic granites have compositions reflecting those of their host rocks, and probably in most cases, the source rocks.S-type granites have higher δ18O values and more evolved Sr and Nd isotopic compositions, although the radiogenic isotope compositions overlap with I-types. Although the isotopic compositions lie close to a mixing curve, it is thought that the amount of mixing in the source rocks was restricted, and occurred prior to partial melting. I-type granites are thought to have been derived from deep crust formed by underplating and thus are infracrustal, in contrast to the supracrustal S-type source rocks.Crystallisation of feldspars from felsic granite melts leads to distinctive changes in the trace element compositions of more evolved I- and S-type granites. Most notably, P increases in abundance with fractionation of crystals from the more strongly peraluminous S-type felsic melts, while it decreases in abundance in the analogous, but weakly peraluminous, I-type melts.

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White, A. J. R., and B. W. Chappell. "Some supracrustal (S-type) granites of the Lachlan Fold Belt." Earth and Environmental Science Transactions of the Royal Society of Edinburgh 79, no. 2-3 (1988): 169–81. http://dx.doi.org/10.1017/s026359330001419x.

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ABSTRACTS-type granites have properties that are a result of their derivation from sedimentary source rocks. Slightly more than half of the granites exposed in the Lachlan Fold Belt of southeastern Australia are of this type. These S-type rocks occur in all environments ranging from an association with migmatites and high grade regional metamorphic rocks, through an occurrence as large batholiths, to those occurring as related volcanic rocks. The association with high grade metamorphic rocks is uncommon. Most of the S-type granites were derived from deeper parts of the crust and emplaced at higher levels; hence their study provides insights into the nature of that deeper crust. Only source rocks that contain enough of the granite-forming elements (Si, Al, Na and K) to provide substantial quantities of melt can produce magmas and there is therefore a fertile window in the composition of these sedimentary rocks corresponding to feldspathic greywacke, from which granite magmas may be formed.In this paper, three contrasting S-type granite suites of the Lachlan Fold Belt are discussed. Firstly, the Cooma Granodiorite occurs within a regional metamorphic complex and is associated with migmatites. It has isotopic and chemical features matching those of the widespread Ordovician sediments that occur in the fold belt. Secondly, the S-type granites of the Bullenbalong Suite are found as voluminous contact-aureole and subvolcanic granites, with volcanic equivalents. These granites are all cordierite-bearing and have low Na2O, CaO and Sr, high Ni, strongly negative εNd and high 87Sr/86Sr, all indicative of S-type character. However, the values of these parameters are not as extreme as for the Cooma Granodiorite. Evidence is discussed to show that these granites were derived from a less mature, unexposed, deeper and older sedimentary source. Other hypotheses such as basalt mixing are discussed and can be ruled out. The Strathbogie Suite granites are more felsic but all are cordierite-bearing and have chemical and other features indicative of an immature sedimentary source. They are closely associated with cordierite-bearing volcanic rocks. The more felsic nature of the suite results in part from crystal fractionation. It is suggested that the magma may have entered this “crystal fractionation” stage of evolution because it was a slightly higher temperature magma produced from an even less mature sediment than the Bullenbalong Suite. The production of these S-type magmas is discussed in terms of vapour-absent melting of metagreywackes involving both muscovite and biotite. The production of a magma in this way is consistent with the low H2O contents and geological setting of S-type granites and volcanic rocks in the Lachlan Fold Belt.

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Massey, C. "Corridor Health Survey, of the Upper Lachlan Catchment, Central West, New South Wales." Australian Mammalogy 20, no. 2 (1998): 309. http://dx.doi.org/10.1071/am98333.

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A major survey of stream corridor health was undertaken in the upper Lachlan Catchment. The survey provides a benchmark assessment of the riverine environment condition. The following attributes were examined: reach environments, channel habitat, cross-section analysis, bank condition and composition, bed and bar condition, riparian vegetation (presence and structure), aquatic habitat analysis, scenic, recreational and conservation values. This paper outlines some of the prelimin~ results related to the assessment of riverine vegetation in this catchment an area of approximately 35 000 km. The survey found that 77% of the riparian vegetation was highly degraded, 10% in poor condition, 4% moderate and 3% in good condition. Six percent of the upper catchment's riparian vegetation was in pristine condition, mostly confined to tributaries of the Abercrombie River. The average width of the riparian zone in the Upper Lachlan Catchment is 12.2 m. This approximates to one or possibly two mature tree widths (species dependant). Trees are generally confined to the banks of water courses and there is very little diversity, structural or species, in the shrub and ground cover understorey. Some implications for platypus conservation are discussed.

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