Cenozoic Stratigraphy of the Eucla Basin
The Eucla Basin extends inland as far as 350 km from the present
coastline and seaward some 200 km to the modern shelf edge and upper
slope. Inland, the Eucla Basin succession thins and "feathers" out against
Precambrian basement; it gradually thickens southward to its thickest
point beneath the modern shelf edge (Fig. 2). Apart from the basal
siliciclastic sequence both offshore (Sequence 7) and onshore (Hampton
Sandstone), and a thin, transgressive, paleovalley-filling and strandline
succession of terrigenous clastics on the inland margins of the basin, the
Eucla Basin succession is entirely carbonate.
The succession is basically divisible into two mega-sequences: a Mesozoic
(?Late Jurassic-Cenomanian; Stagg et al., 1990) siliciclastic-dominated
syn- to early postrift section and a Cenozoic (Paleocene to Holocene),
predominantly carbonate-dominated section, separated by a major,
basinwide unconformity. The subject of the bulk of this drilling leg is the
upper succession, which makes up an overall sigmoid-shaped series of
sequences reaching a maximum thickness beneath the present-day outer
shelf (Fig. 2). The stratigraphy of the lower, Mesozoic succession can be
derived from the sequence intersected in the Jerboa-1 exploration well
(Fig. 1); however, little information on the upper, Cenozoic section was
obtained from this hole.
The extensive erosional unconformity at the top of the synrift section
forms an easily recognizable and mappable surface. Seven
unconformity-bounded seismic sequences have been recognized overlying
this unconformity (Fig. 2). One of the most striking elements of this
seismic stratigraphic analysis is the identification of numerous
mound-shaped structures occurring throughout the Cenozoic succession,
which have been interpreted as biogenic mounds (Feary and James, 1995).
These structures are likely to preserve a detailed record of cool-water
faunal community relationships and potentially to provide an analogue for
cool-water mounds recognized in the rock record, but for which no modern
analogues have previously been identified.
The ages assigned to this succession are extremely tentative and are
based on (1) correlation of Sequence 6B with the onshore Eucla Group (Fig.
2); (2) the similarity in depositional style between the Sequence 7
progradational wedge and ?Paleocene-early Eocene progradational
sequences elsewhere along Australia's southern margin; and (3) the
division of the remainder of the sequences into a reasonable
time-stratigraphic framework. On this basis, the offshore sequences can
be placed in a stratigraphic framework (based on Feary and James, in
press):
Sequence 7: Paleocene-middle Eocene progradational
siliciclastic wedge deposited in a depositional sag,
representing initial transgressive sedimentation.
Sequence 6A: middle-late Eocene to early-middle Miocene
deep-water carbonates forming a multilobed sediment apron.
Sequence 6B: cool-water ramp carbonates with biogenic
mounds (middle-late Eocene to Oligocene), overlain by an
upper, warm-water, flat-topped platform rimmed by the
?early middle Miocene "Little Barrier Reef" (Feary and James,
1995).
Sequence 5: small late middle Miocene lowstand sediment
wedge with restricted distribution, lying at the foot of the
steepest part of the progradational carbonate shelf
escarpment zone.
Sequence 4: extensive late Miocene aggradational deep-water
carbonate ramp sequence.
Sequence 3: latest Miocene and early Pliocene highstand
aggradational deep-water carbonate ramp sequence.
Sequence 2: thick succession of highstand, Plio-Pleistocene
cool-water carbonates with spectacular clinoform ramp
geometry that forms most of the modern outer shelf and
contains large deep-water biogenic mounds.
Sequence 1: thin Quaternary deep-water drape.
Existing Data
Present knowledge of the western Great Australian Bight margin is based
on extensive, high quality seismic reflection data, together with a single
oil exploration drill hole, which provides little information about the
Cenozoic succession. The original Leg 182 drilling proposals (James and
Feary, 1993; Feary et al., 1994) were based on detailed seismic
stratigraphic interpretation (Feary and James, in press) of a grid of 2,350
km of high-quality, regional 2-D seismic reflection lines. These lines
were collected and processed by the Japan National Oil Corporation (JNOC)
in 1990 and 1991, over an area of 155,000 km2 on the
continental shelf
and upper slope of the western Great Australian Bight. An additional 1380
km of moderate-quality, regional 2-D seismic lines, collected by Esso
Australia in 1979 and reprocessed by JNOC, were also used to fill gaps in
the JNOC dataset. The 1996 seismic-site survey cruise (Feary, 1995)
collected high-resolution, 80 channel generator-injector (GI) gun seismic
data as 0.5 nmi-spaced grids centered on each site, together with
tie-lines between sites. These data permitted minor refinements of some
site locations to avoid potential safety concerns.
Jerboa-1 was drilled by Esso/Hematite in 1980 as a wildcat oil
exploration well in 761-m water depth, above a prominent tilted basement
fault block located in the southern half-graben of the Eyre Sub-basin (Bein
and Taylor, 1981). Jerboa-1 penetrated 1738 m of a Cenozoic and
Cretaceous sedimentary section before bottoming in Precambrian
metabasalt basement and did not encounter any significant hydrocarbon
shows. The top 232 m were washed down and cased, so that only 145 m of
Tertiary section were actually drilled and logged. No cores were cut in
this interval, so lithologic and biostratigraphic inferences are based on
cuttings and downhole logs. Thermal modelling and vitrinite data (Stagg et
al., 1990) indicate that the entire sedimentary section at Jerboa-1 is
thermally immature (Rv <0.65%).
SCIENTIFIC OBJECTIVES
Leg 182 drilling in the Great Australian Bight will allow six fundamental
scientific topics to be addressed:
1.The paleoceanographic history of a carbonate-dominated, mid-latitude
continental margin and adjacent basin during evolution of the Southern
Ocean. As the Southern Ocean is one of the major controlling influences on
global circulation and climate, it is imperative that the oceanic history of
this region be refined as much as possible. However, at present the
paleoceanographic development of this area is not nearly as well known as
that of the high latitude North Atlantic (Kennett and Barron, 1992).
Although there are numerous paleoceanographic problems that can be
answered by the Leg 182 drilling transect, four stand out as critical.
(a) The relationship between circulation patterns in the deep ocean
and on the shelf during times of warm vs. cold ocean conditions. The
stratigraphic record in the Southern Ocean is punctuated with
numerous breaks in sedimentation that are attributed to erosive
periods related to increased circulation during initiation of the
Circum-Antarctic Current (Miller et al., 1987; Kennett and Barker,
1990). Although such hiatuses are thought to develop on deep
margins during times of lower sea level and to correlate with
unconformities on the continental shelf, there are apparently
continuous onshore sequences of Oligocene shelf carbonates
deposited while there was erosion or nondeposition of the entire
Oligocene on the adjacent ocean floor.
(b) The precise timing and nature of the opening of the Tasman
Gateway. Subsidence of the Tasman Rise, which permitted initiation
of the cold circum-Antarctic circulation and thermal isolation of
Antarctica, is one of the most important developments in Cenozoic
paleoceanography (Kennett, 1982). The history of this event is poorly
constrained because so much of the oceanic record is missing as a
result of seafloor erosion. The Leg 182 shelf-to basin transect is
sufficiently proximal to the Tasman Rise that it should contain an
excellent record of the paleoceanographic development of this
seaway.
(c) The evolution and effect of the Leeuwin Current. The first
evidence for the existence of the Leeuwin Current occurs in middle
Eocene time, when currents from the Indian Ocean were deflected
into the elongate proto-Great Australian Bight embayment. In
support of this, the record of warm-water intervals is more common
in the west than it is in the east, implying that the source of the
water is from the west. Studies of Quaternary cores from the Great
Australian Bight suggest a complex interplay between the Leeuwin
Current and the West Wind Drift. This interplay appears to have had
dramatic effects on primary productivity, as the Leeuwin Current is
a source of warm oligotrophic waters, whereas the West Wind Drift
causes upwelling of cooler eutrophic waters.
(d) The relationship between primary productivity and cool-water
carbonate development. The Leg 182 shelf-to-basin transect should
contain an important record of paleoproductivity linked to upwelling.
Such periods should be recorded in the biota by low species
diversity, high numbers of individuals, increased sedimentation rate,
and distinctive changes in stable isotopic and trace-element
compositions.
2.The formulation of models for carbonate sedimentation on continental
margins bathed predominantly by cool oceanic waters. The deposition and
accumulation of platform (neritic) carbonate sediments under cool-water
(~<20°C) conditions is poorly understood compared to warm-water
carbonates, primarily because the database is so small (Nelson, 1988;
James and Kendall, 1992). Yet, because of their dominantly skeletal
composition, nutrient-dependent biology, and low diagenetic potential,
cool-water carbonates record the history of oceanic change in ways that
are profoundly different from tropical carbonates. In hydrodynamic terms,
cool-water carbonate shelves are hybrids, possessing some of the
characteristics of both terrigenous clastic shelves and warm-water
carbonate shelves. Sediments are produced on the shelf, in contrast to
terrigenous clastic shelves where sediment is transported onto the shelf
from the hinterland. Without the elevated rim that typifies warm-water
carbonate shelves, however, the sediments are subject to the full sweep
of oceanic waves and swells, as they are on terrigenous clastic shelves.
Cenozoic exposures of inner-shelf facies in Australia suggest that storm-
and wave-dominated processes tend to control deposition. By contrast,
many contemporaneous deposits in New Zealand are clearly tide
dominated. Are the models of wave-dominated shelf deposition developed
onshore applicable throughout the Cenozoic? All seismic profiles across
the southern margin of Australia indicate that a large proportion of the
youngest part of the succession is made up of prograding clinoforms
(James and von der Borch, 1991; Feary and James, in press). Such
clinoforms seem to be a signature of cool-water platforms and ramps and
are postulated to be a product of accumulation dynamics (Boreen and
James, 1993). There is little information regarding the composition of
these deposits; specifically, are they produced by in-place, enhanced
bioproduction along the shelf edge, or are they made up of finer grained
material produced on the shelf and swept offshore to accumulate below
the wavebase?
3.Determination of the Southern Ocean basin sea-level record, and the effect of sea-level fluctuations on stratigraphic packaging and early diagenesis of cool-water carbonates. The Eucla margin is rich in biogenic carbonate sediments that respond in a sensitive way to variations in sea level and contain vital geochemical information needed for linking sea-level changes to paleoceanography. This information can then be utilized to address two major questions of global and temporal significance. (a) What is the detailed sea-level history of the Southern Ocean basin, and can it be linked to paleoceanographic variations? Specifically, the southern Australian neritic shelf record, derived largely from onshore successions in which the marine record is preserved only in highstand systems tracts, appears to be at odds with the global model (Haq et al., 1987) during several critical periods. Is this because the sediments were deposited in cool water? By using a combination of physical stratigraphy and proxy paleoenvironmental parameters in a much more expanded section than exists onshore, the well-preserved Eocene to Oligocene and early to middle Miocene successions will permit a thorough testing of this part of the sea level curve and resolution of specific eustatic events. The late Miocene to Pliocene sequence is unknown onshore except for the early Pliocene highstand, and so this will be the first clear record of this component of the sea-level record in the region. (b) How do cool-water carbonate platforms respond to changes in sea level? Carbonate platforms, with their chemically metastable sediments born largely in place, are particularly responsive to changes in seawater temperature and chemistry and variations in sea state and sea level. To date, most information on carbonate platforms comes from rimmed, warm-water platforms (Kendall and Schlager, 1981; Sarg, 1988). There is almost no information on the manner in which cool-water carbonate platforms respond to changes in these critical parameters at a variety of different time scales. Specifically, we require information to describe how different segments of the shelf react during different parts of the sea-level cycle and to determine whether cold- and warm-water carbonate platforms have basically different depositional geometries as a result of the different ways the carbonate factory responds to sea-level changes. 4.The circulation patterns of shallow subsurface fluids in an area of low hydraulic gradient and minimal recharge. The Eucla margin is one of the few modern shelves where the onshore recharge zone is an areally vast, flat-lying karst (the Nullarbor Plain). The high primary depositional permeability of winnowed grainstones of the Eucla Shelf and the lack of early cementation suggest that significant groundwater circulation may occur, at least at shallow depths. The drive for such a circulation may come from temperature contrasts between cool ocean waters and groundwaters warmed by geothermal heat flux (and possibly volcanics) within the shelf, concentrating waters on the shelf margin (Simms, 1984). Alternatively, despite inland aridity, recharge occurring over the vast continental hinterland may drive brackish to saline waters southward to discharge through the flooded shelf. Such a circulation has been recognized by James (1992) and is associated with cave development on the Nullarbor Plain (James et al., 1989). In contrast to the long-lived nature of the above systems, differences in sea-surface elevation, on and off the shelf, associated with regional wave buildup (Feary, 1995), current flow (Rockford, 1986), and atmospheric pressure system changes may cause pumping of marine waters into and out of the platform (Marshall, 1986). 5.Early seafloor and shallow burial diagenesis and dolomitization of calcite-dominated sediments. Cool-water carbonates exhibit a radically different pattern of diagenesis from that of tropical aragonitic carbonates. Slow sedimentation permits seafloor lithification by intermediate Mg-calcite cements, but these appear to be volumetrically limited and localized to omission surfaces and hardgrounds, which are ubiquitous in the inner platform. Indeed, both shallow-marine and meteoric cements appear to be very sparse, with magnesium being lost from high-Mg calcite to low Mg calcite during grain recrystallization. Sparse calcium-rich dolomites may be present (Reeckmann, 1988; Bone et al., 1992), and at some locations replacement can be pervasive (James et al., 1993), although the fine subtidal evaporation related dolomites typical of tropical platforms are absent. It is not known whether dolomitization is episodic, as recognized in other present-day platforms (Vahrenkamp, et al. 1991; McKenzie et al., 1993), or occurred over extended time periods. The Eucla margin carbonates will provide an opportunity to determine the present-day associations among groundwater circulation, fluid geochemistry, and diagenetic products, and by inference from the temporal and spatial distribution of ancient diagenetic components, those that occurred under different conditions in the past. This has the potential to provide fundamental insights into the diagenesis of cool-water, open-shelf carbonates, which are direct analogues for the comparable carbonate platforms that were ubiquitous during Paleozoic and other times. 6.The pace and style of evolution of mid-latitude oceanic and neritic biotas. The Leg 182 drilling transect offers the opportunity for pioneering analysis of the Cenozoic evolution of cool-water calcareous biota, with direct applicability to studies of ancient carbonate platforms presently lacking modern analogues. Linked information from the neritic and oceanic high- to mid-latitude carbonate realm should produce an unmatched record of paleobiological information. Specifically, the patterns and modes of speciation and diversification of coeval shallow- and deep-water benthic organisms as well as contemporaneous planktonic biota should be revealed. By comparing these results with those from Antarctica and the northeast Australian shelf, the geography of such processes and their relationship to physiochemical factors should be discernible. DRILLING STRATEGY The Leg 182 drilling strategy must be developed with the knowledge that although ODP has great experience with drilling deep-water pelagic carbonates, it is difficult to predict drilling conditions in the cool-water carbonates at the shallower sites. Accordingly, operational considerations may dictate that significant changes to drilling strategies are necessary on site. In particular, although easily drilled nanno-foram and foram-nanno oozes are expected to dominate the upper sequences at each site, there is the possibility that thin bioclastic grainstone horizons and/or thin chert horizons may complicate drilling at the shallowest sites. In addition, the order in which sites are drilled will need to be flexible to accommodate operational restrictions dependent on sea state for the sites in less than 650 m water depth (Sites GAB-05B, GAB-06B, GAB-07A, GAB-08A, and GAB 09A). This will be particularly important for the sites located in less than 300 m water depth (Sites GAB-06B and GAB-09A), where calm conditions will be imperative. The Leg 182 operational plan is summerized in Table 1. Triple coring with the advanced hydraulic piston corer (APC), extended core barrel corer (XCB), and rotary core barrel corer (RCB) will be carried out at the four high-resolution paleoceanography and sea-level sites (Sites GAB-01C, GAB-02B, GAB-06B, and GAB-13B), which comprise the shelf-to-basin transect (water depth range of 332-4465 m). After the cores and downhole logs have been tied to the extensive seismic data in the area, these sites will provide the fundamental basis for regional stratigraphic and lithologic characterization. Lithologies intersected at all these sites should pass from carbonate oozes in the upper part of the holes down into more indurated calcareous siliciclastic sediments at the base. The 500- to 600-m high-resolution records of Plio-Pleistocene sea-level fluctuations within carbonate oozes targeted at Sites GAB-07A, GAB-08A, and GAB 09A should be achievable with double APC and XCB drilling, with triple APC at Site GAB-09A providing additional resolution. The sites predominantly targeting cool-water carbonate facies objectives (Sites GAB-03B, GAB 04B, and GAB-05B) should be drilled using double APC and XCB, with the deeper (Cretaceous) parts of Site GAB-04B possibly requiring RCB, and the siliciclastic sequence in the deeper part of Site GAB-05B certainly requiring RCB. Direct seismic ties connecting the dry oil exploration well Jerboa-1 (Fig. 1) to all sites_except Site GAB-01C and GAB-13B_demonstrate that there is negligible likelihood of encountering hydrocarbons, and vitrinite reflectance data show that most or all of the sedimentary succession underlying these shallower sites is thermally immature. Water depths at Sites GAB-01C (3884 m) and GAB-13B (4465 m) are too great for any significant safety risks. LOGGING PLAN All sites should be logged with standard logging tool strings (triple-combo, formation microscanner [FMS]/sonic), together with deployment of the well seismic tool (WST) and geological high-sensitivity magnetometer tool (GHMT) at selected sites. The geophysical logs (triple-combo) will be important for evaluating the lithostratigraphic response of cool-water carbonates to sea-level and climatic fluctuations. The fine-scale characteristics of the bedding, including pore spaces, bioturbation, fractures, and stylolites, may be imaged through FMS. Integrated interpretation of FMS and geophysical logs should provide a good complement to cores in describing the lithostratigraphy. Diagenesis in carbonates usually is well expressed through changes in porosity and chemical precipitation of soluble elements (such as uranium), leading to large changes in log properties seen on sonic, resistivity, density, and neutron gamma-ray logs. Thus, the diagenetic changes in the carbonate sediments, another key objective of the leg, may be evaluated through the petrophysical response measured in the wireline logs. Magnetostratigraphic characterization at selected deeper penetration sites using the GHMT string should also contribute to the sedimentary/stratigraphic objectives and intersite correlation. Interstitial fluid characterization from cores will be the primary tool for the fluid-flow objectives, with logging data being of secondary importance. However, the assessment of fracture networks and basic fluid properties using sonic and resistivity logs, together with FMS images should provide an important contribution to this leg objective. A detailed correlation between cores and logs and the extensive suite of high-quality seismic reflection data, including the closely spaced site survey grids and regional 2-D lines, will be critical for understanding the 3-D architecture of the Cenozoic sequences and for compiling a detailed sequence stratigraphy. Accordingly, check-shot (WST) surveys, at 30- to 50-m spacing, should also be run at all sites_except Site GAB-08A (where data from adjacent Sites GAB-07A and GAB-09A will be applicable). SAMPLING STRATEGY During Leg 182, the upper sections (approximately 200 m) at all sites will be recovered by either triple APC coring (four sites) or double APC coring (four sites). Sampling for high-resolution isotopic, sedimentologic, and micropaleontologic studies at these sites will be conducted after construction of the spliced composite section. Only low-resolution sampling will be carried out aboard ship to support description/characterization, facilitate pilot studies, and provide material for projects that do not require high-temporal resolution. High-resolution sampling will be deferred until after the cruise. Whole-round sampling for pore-water geochemical analyses is anticipated at a higher resolution than the typical routine ODP scheme. The archive halves (permanent and temporary) in all holes will not be sampled aboard ship, and the permanent archive will be designated postcruise. The sampling plan for Leg 182 must be approved by the sampling allocation committee (SAC), consisting of the Co-chief Scientists, Staff Scientist, and Curatorial representative. The initial sampling plan is preliminary and can be modified depending upon actual material recovered and collaborations that may evolve between scientists during the leg. PROPOSED SITES Sites GAB-01C, GAB-02B, and GAB-13B Sites GAB-01C (southern Australian upper continental rise), GAB-02B (mid-upper slope), and alternate GAB-13B (middle continental rise) are paleoceanographic sites located to intersect pelagic sections that collectively span the entire Cenozoic succession and a substantial part of the Late Cretaceous section. These sites compose the deeper water component of the shelf-to-basin transect. The principal objective at these sites is to obtain a complete record of the Cenozoic section in a deep oceanic setting, with the principal aim of elucidating the evolution of the Circum-Antarctic Current within the evolving seaway between Australia and Antarctica. As the condensed section in the Jerboa-1 well contains early Oligocene faunas, there is a high probability that the intermediate and deep pelagic successions will together contain a more expanded record of this critically important time of Antarctic ice-cap evolution and Southern Ocean paleoceanographic development. Sites GAB-03B and GAB-04B Sites GAB-03B and GAB-04B are located to intersect the Eocene to early middle Miocene section deposited in lobes on the upper slope, coeval with deposition of the extensive carbonate platform on the continental shelf. In addition, these sites will also intersect an early Neogene succession poorly sampled at other sites; a highly condensed late Neogene succession; and the upper part of the marine Cenomanian section at Site GAB-04B. The principal objective at these sites is to collect a detailed record of Paleogene-early Neogene temperate to subtropical, mid-latitude sedimentation in an upper slope environment and to recover a record of marine flooding of the evolving rift basin in the Cenomanian (Site GAB-04B). Sites GAB-05B and GAB-06B Sites GAB-05B and GAB-06B are located to intersect distal (Site GAB-05B) and proximal (Site GAB-06B) parts of the Paleocene to middle Eocene progradational siliciclastic wedge. In addition, these sites will intersect a major portion of the overlying Neogene succession (Seismic Sequences 2 to 4). The principal objective at these sites is to recover a detailed record of shelf-edge siliciclastic deposition to evaluate the sedimentary response to Paleogene sea-level fluctuations and to evaluate the complex interaction between sea-level variation, accommodation space, and subsidence evident in stratal patterns. Sites GAB-07A, GAB-08A, and GAB-09A Sites GAB-07A, GAB-08A (alternate), and GAB-09A will intersect a spectacular set of late Neogene (?Plio-Pleistocene) clinoforms immediately seaward of the present-day shelf edge. Site GAB-07A will intersect the lowest, more condensed portion of the clinoform sequence, but will also have the best record of the youngest clinoforms; Site GAB-08A will intersect a ?Pleistocene Holocene biogenic mound immediately below the seafloor, together with the best record of the middle part of the clinoform sequence; and Site GAB-09A will intersect a buried biogenic mound originally formed immediately below the paleoshelf edge, together with the best record of the oldest part of the clinoform sequence. The principal objective at these sites is to collect detailed, high-resolution profiles through a late Neogene shelf-edge (high energy) to upper slope (low energy) succession deposited within a cool-water carbonate environment to determine the response of such a depositional system to Plio-Pleistocene sea-level fluctuations. REFERENCES Bein, J., and Taylor, M.L., 1981. The Eyre Sub-basin: recent exploration results. The APEA Journal, 21:91-98. Bone, Y., James, N.P., and Kyser, T.K., 1992. Syn-sedimentary detrital dolomite in Quaternary cool-water carbonate sediments, Lacepede Shelf, south Australia. Geology, 20:109-112. Boreen, T.D., and James, N.P., 1993. Holocene sediment dynamics on a cool-water carbonate shelf, southeastern Australia. Jour. Sed. Petr., 63:574-588. Davies, H.L., Clarke, J.L.A., Stagg, H.M.J., Shafik, S., McGowran, B., and Willcox, J.B., 1989. Maastrichtian and younger sediments from the Great Australian Bight. Bureau Mineral Resources, Report 288. Feary, D.A., 1995. Proposal for an ODP site survey cruise by the R/V Rig Seismic in the western Great Australian Bight. Australian Geological Survey Organization, Record 1995/67. Feary, D.A., and James, N.P., 1995. Cenozoic biogenic mounds and buried Miocene (?) barrier reef on a predominantly cool-water carbonate continental margin, Eucla Basin, western Great Australian Bight. Geology, 23:427-430. Feary, D.A., and James, N.P., in press. Seismic Stratigraphy and Geological Evolution of the Cenozoic, Cool-water, Eucla Platform, Great Australian Bight. Amer. Assoc. Petr. Geol. Bull.. Feary, D.A., James, N.P., and McGowran, B., 1994. Cenozoic Cool-water Carbonates of the Great Australian Bight: reading the record of Southern Ocean evolution, sea level, paleoclimate, and biogenic production. Australian Geological Survey Organization, Record 1994/62. Haq, B.U., Hardenbol, J., and Vail, P.R., 1987. The chronology of fluctuating sea level since the Triassic. Science, 235:1156-1167. Hegarty, K.A., Weissel, J.K., and Mutter, J.C., 1988. Subsidence history of Australia's southern margin: constraints on basin models. Amer. Assoc. Petr. Geol. Bull., 72:615-633. James, J.M., 1992. Corrosion par melange des eaux dans les grottes de la plaine de Nullarbor, Australie. Karst et Evolutions Climatiques: 333-348. James, J.M., Rogers, P., and Spate, A.P., 1989. Genesis of the caves of the Nullarbor Plain, Australia. Proceedings, 10th International Congress on Speleology., Budapest: 263-265. James, N.P., Bone, Y., and Kyser, T.K., 1993. Shallow burial dolomitization of Cenozoic cool-water calcitic deep shelf limestones, southern Australia. Jour. Sed. Petr., 63:528-538. James, N.P., and Feary, D.A., 1993. Great Australian Bight: Evolution of a Cenozoic carbonate continental margin. ODP Drilling Program, Proposal 367-Rev. James, N.P., and Kendall, A.C., 1992. Introduction to carbonate and evaporite facies models. In Walker, R.G., and James, N.P. (Eds), Facies Models, Response to Sea Level Change. Geological Association of Canada: 265-276. James, N.P., and von der Borch, C.C., 1991. Carbonate shelf edge off southern Australia: A prograding open-platform margin. Geology, 19:1005-1008. Kendall, C.St.C.G., and Schlager, W., 1981. Carbonates and relative changes in sea level. Mar. Geol., 44:181-212. Kennett, J.P., 1982. Marine Geology: Englewood Cliffs, NJ, (Prentice-Hall Inc.). Kennett, J.P., and Barker, P.F., 1990. Latest Cretaceous to Cenozoic climate and oceanographic developments in the Weddell Sea, Antarctica: an Ocean Drilling Perspective. In Barker, P.F., Kennett, J.P. et al., Proc. ODP, Sci. Results, Leg 113: College Station, TX (Ocean Drilling Program), 937-960. Kennett, J.P., and Barron, J.A., 1992. Introduction. In Kennett, J.P. and Warnke, D.A. (Eds), The Antarctic Paleoenvironment: A perspective on Global Change. Antarctic Research Series, American Geophysical Union, 56:1-6. McKenzie, J.A., Isern, A.R., Elderfield, H., Williams, A., and Swart, P.K., 1993. Strontium isotope dating of paleoceanographic, lithologic, and dolomitization events on the northeastern Australian Margin, Leg 133. In McKenzie, J.A., Davies, P.J., and Palmer-Julson, A., et al., Proc. ODP, Sci. Results, 133: College Station, TX (Ocean Drilling Program): 489-498. Marshall, J.F., 1986. Regional distribution of submarine cements within an epicontinental reef system: Central Great Barrier Reef, Australia. In Schroeder, J.H., and Purser, B.H. (Eds), Reef Diagenesis: 8-26. Miller, K.G., Fairbanks, R.G., and Mountain, G.S., 1987. Tertiary oxygen isotope synthesis, sea level history and continental margin erosion. Paleoceanography, 2:1-19. Nelson, C.S., 1988. An introductory perspective on non-tropical shelf carbonates. Sediment. Geol., 60:3-14. Reeckmann, S., 1988. Diagenetic alterations in temperate shelf carbonates from south-eastern Australia. Sediment. Geol., 60:209-219. Rockford, D.J., 1986. Seasonal changes in the distribution of Leeuwin Current waters off southern Australia. Aust. J. Mar. Freshwater Res., 37:1-10. Sarg, J.F., 1988. Carbonate sequence stratigraphy, In Wilgus, C.K., et al. (Eds), Sea level change; an integrated approach, SEPM Special Publication, 42:155-181. Simms, M., 1984. Dolomitization by groundwater flow systems in carbonate platforms. Trans. Gulf Coast Assoc. Geol. Soc., 34:411-420. Stagg, H.M.J., Cockshell, C.D., Willcox, J.B., Hill, A.J., Needham, D.J.L., Thomas, B., O'Brien, G.W., and Hough, L.P., 1990. Basins of the Great Australian Bight region: Geology and petroleum potential. Bureau of Mineral Resources, Continental Margins Program, Folio 5. Vahrenkamp, V.C., Swart, P.K., and Ruiz, J., 1991. Episodic dolomitization of late Cenozoic dolomites in the Bahamas: evidence from strontium isotopes. Jour. Sed. Petr., 61:1002-1015. Willcox, J.B., Stagg, H.M.J., Davies, H.L., et al., 1988. Rig Seismic Research Cruises 10 &;11: Geology of the central Great Australian Bight region. Bureau of Mineral Resources, Report 286. FIGURE CAPTIONS Figure 1. Location of the proposed ODP drill sites in the western Great Australian Bight. Figure 2. Schematic N-S diagram from the Nullarbor Plain to the upper continental slope across the Eyre Terrace (along longitude 128øE), showing the distribution and internal relationships of seven Cenozoic sequences (unshaded) defined from seismic data, overlying Mesozoic synrift siliciclastic sequences and Precambrian crystalline basement (after Feary and James, in press). Vertical scales are approximate. SITE SUMMARIES** Site: GAB-01C Priority: 1 Position: 34ø23.4672'S, 127ø35.4393'E Water Depth: 3884 m Sediment Thickness: ÷5950 m Approved Maximum Penetration: 700 m Seismic Coverage: Intersection of AGSO Lines 169/08 (SP 729.5) and 169/11 (SP 1962.5) Objectives: The objectives of GAB-01C are to 1. Recover pelagic ooze from the upper continental rise to construct a Cenozoic and Late Cretaceous paleoceanographic record of the opening of the Southern Ocean and the development of the Circum-Antarctic Current. 2. Determine the history of Cenozoic and Late Cretaceous carbonate compensation depth (CCD) fluctuations and deep-water mass variations during the evolution of the Southern Ocean (in conjunction with Sites GAB-02B and GAB-13B). 3. Determine depositional and diagenetic facies on the upper continental rise. Drilling Program: Triple APC, XCB, RCB Logging and Downhole Operations: Triple combo, FMS/Sonic, GHMT, WST Nature of Rock Anticipated: Nanno-foram ooze and chalk (590 m), sandstone (24 m); and volcanics (1 m) Site: GAB-02B Priority: 1 Position: 33ø32.3730'S, 128ø54.3002'E Water Depth: 1043 m Sediment Thickness: ÷4600 m Approved Maximum Penetration: 1750 m Seismic Coverage: Intersection at SPs 428 and 3550 on AGSO Line 169/07 Objectives: The objectives of GAB-02B are to 1. Recover pelagic ooze from the middle-upper slope to construct a Cenozoic and Late Cretaceous paleoceanographic record of the opening of the Southern Ocean and the development of the Circum-Antarctic Current. 2.Determine the history of Cenozoic and Late Cretaceous CCD fluctuations and intermediate water mass variations during the evolution of the Southern Ocean (in conjunction with Sites GAB-01C and GAB-13B). 3.Determine depositional and diagenetic facies on the middle-upper slope. Drilling Program: Triple APC, XCB, RCB Logging and Downhole Operations: Triple combo, FMS/Sonic, GHMT, WST Nature of Rock Anticipated: Nanno-foram ooze and chalk with minor wackestone (1400 m); indurated sandy calcareous mudstone (310 m) Site: GAB-03B Priority: 1 Position: 33ø31.7255'S, 127ø15.8565'E Water Depth: 704 m Sediment Thickness: ÷2830 m Approved Maximum Penetration: 550 m Seismic Coverage: Intersection at SPs 1668.5 and 4696 on AGSO Line 169/01 Objectives: The objectives of GAB-03B are to 1.Collect a detailed record of Paleogene-early Neogene temperate to subtropical, mid-latitude sediments deposited as lowstand sediment lobes in an upper slope environment. 2.Contribute to the upper slope component of the shelf-to-basin paleoceanographic transect. 3.Evaluate sea-level control on Neogene facies within an upper slope setting; in particular, to evaluate stratigraphic response to eustatic oscillations by comparison with equivalent time intervals in shelf and deep oceanic settings. 4. Determine diagenetic history and processes within Neogene upper slope facies. Drilling Program: Double APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic, WST Nature of Rock Anticipated: Nanno-foram ooze and chalk with minor wackestone (320 m); sandy calcareous mudstone (190 m) Site: GAB-04B Priority: 1 Position: 33ø30.5568'S, 128ø03.9950'E Water Depth: 790 m Sediment Thickness: ÷950 m Approved Maximum Penetration: 570 m Seismic Coverage: Intersection at SPs 1131.5 and 3209.5 on AGSO Line 169/03 Objectives: The objectives of GAB-04B are to 1.Collect a detailed record of Paleogene-early Neogene temperate to subtropical, mid-latitude sediments deposited as lowstand sediment lobes in an upper slope environment. 2.Contribute to the upper slope component of the shelf-to-basin paleoceanographic transect. 3.Evaluate sea-level control on Neogene facies within an upper slope setting; in particular, to evaluate stratigraphic response to eustatic oscillations by comparison with equivalent time intervals in shelf and deep oceanic settings. 4.Determine diagenetic history and processes within Neogene upper slope facies. 5.Collect a record of marine flooding of the evolving rift basin between Australia and Antarctica from the Cenomanian. Drilling Program: Double APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic, WST Nature of Rock Anticipated: Nanno-foram ooze and chalk with minor wackestone (330 m); sandy calcareous mudstone (210 m) Site: GAB-05B Priority: 1 Position: 33ø25.2122'S, 127ø36.1382'E Water Depth: 488 m Sediment Thickness: ÷3910 m Approved Maximum Penetration: 600 m Seismic Coverage: Intersection at SPs 995 and 13195 on AGSO Line 169/13 Objectives: The objectives of GAB-05B are to 1.Recover a detailed record of shelf-edge siliciclastic deposition (at a "distal" site compared with Site GAB-06B) to evaluate the sedimentary response to Paleogene sea-level fluctuations and to evaluate the complex interaction between sea-level variation, accommodation space, and subsidence. 2.Determine the characteristics of cool-water carbonate facies within the Neogene succession (Sequences 2 to 4). 3.Determine paleoceanographic parameters within a shelf-edge setting in Sequences 2 to 4, to complement other components of the shelf-to-basin transect. 4.Evaluate sea-level control on Neogene facies within an upper slope/shelf-edge setting (cf Sites GAB-03B and GAB-04B). 5.Evaluate the diagenetic history and processes within Neogene facies in an upper slope/shelf edge setting. Drilling Program: Double APC, XCB, RCB Logging and Downhole Operations: Triple combo, FMS/Sonic, GHMT, WST Nature of Rock Anticipated: Nanno-foram ooze/chalk and wackestone with minor grainstone (350 m); interbedded calcareous mudstone and sandstone (230 m) Site: GAB-06B Priority: 1 Position: 33ø18.9842'S, 127ø36.1287'E Water Depth: 220 m Sediment Thickness: ÷1405 m Approved Maximum Penetration: 720 m Seismic Coverage: Intersection at SP's 1916 and 7400 on AGSO Line 169/13 Objectives: The objectives of GAB-06B are to 1.Recover a detailed record of shelf-edge siliciclastic deposition (at a "proximal" site compared with Site GAB-05B) to evaluate the sedimentary response to Paleogene sea-level fluctuations and to evaluate the complex interaction between sea-level variation, accommodation space, and subsidence. 2.Determine the characteristics of cool-water carbonate facies within the Neogene succession (Sequences 2 to 4). 3.Determine paleoceanographic parameters within a shelf-edge setting in Sequences 2 to 4 to complement other components of the shelf-to-basin transect. 4.Evaluate sea-level control on Neogene facies within an upper slope/shelf-edge setting (cf Sites GAB-03B and GAB-04B). 5.Evaluate the diagenetic history and processes within Neogene facies in an upper slope/shelf edge setting. Drilling Program: Triple APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic (WST if time permits) Nature of Rock Anticipated: Nanno-foram ooze/chalk and wackestone with minor grainstone (560 m); interbedded calcareous mudstone and sandstone (135 m) Site: GAB-07A Priority: 1 Position: 33ø21.4498'S, 128ø28.8772'E Water Depth: 480 m Sediment Thickness: ÷2645 m Approved Maximum Penetration: 580 m Seismic Coverage: Intersection at SPs 600 and 10569.5 on AGSO Line 169/05 Objectives: The objectives of GAB-07A are to 1.Collect detailed, high-resolution profiles through a late Neogene succession deposited within a low-energy, cool-water carbonate environment to determine the response of such a depositional system to Plio-Pleistocene sea-level fluctuations. 2.Obtain a high-resolution record of late Neogene paleoceanographic variation within a middle-upper slope setting, as a component of the shelf-to-basin paleoceanographic transect. 3.Evaluate the diagenetic history of calcitic sediments deposited within a low-energy environment below storm wave base, for comparison with the higher energy environments at Sites GAB-08A and GAB-09A. Drilling Program: Double APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic, WST Nature of Rock Anticipated: Foram-nanno ooze and chalk; minor wackestone Site: GAB-08A Priority: 2 Position: 33ø19.5628'S, 128ø28.8788'E Water Depth: 332 m Sediment Thickness: ÷2880 m Approved Maximum Penetration: 650 m Seismic Coverage: Intersection at SPs 879 and 8253.5 on AGSO Line 169/05 Objectives: The objectives of GAB-08A are to 1.Collect a detailed, high-resolution profile through a late Neogene succession deposited within a moderate-energy, cool-water carbonate environment to determine the response of such a depositional system to Plio-Pleistocene sea-level fluctuations. 2. Obtain a high-resolution record of late Neogene paleoceanographic variation within an upper slope setting, as a component of the shelf-to-basin paleoceanographic transect. 3.Evaluate the diagenetic history of calcitic sediments deposited within a moderate-energy environment below storm wavebase, for comparison with the higher energy environment at Site GAB-09A. Drilling Program: Triple APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic, GHMT, WST Nature of Rock Anticipated: Wackestone; foram-nanno ooze and chalk; minor grainstone Site: GAB-09A Priority: 1 Position: 33ø17.3793'S, 128ø28.8748'E Water Depth: 200 m Sediment Thickness: ÷2480 m Approved Maximum Penetration: 600 m Seismic Coverage: Intersection at SPs 1202 and 5574.5 on AGSO Line 169/05 Objectives: The objectives of GAB-09A are to 1.Collect detailed, high-resolution profiles through a late Neogene succession deposited within a high-energy, cool-water carbonate environment to determine the response of such a depositional system to Plio-Pleistocene sea-level fluctuations. 2.Obtain a high-resolution record of late Neogene paleoceanographic variation within a shelf edge setting, as a component of the shelf-to-basin paleoceanographic transect. 3.Evaluate the diagenetic history of calcitic sediments deposited within a high-energy environment below storm wave base, for comparison with the lower energy environments at Sites GAB-07A and GAB-08A. Drilling Program: Triple APC, XCB Logging and Downhole Operations: Triple combo, FMS/Sonic, WST Nature of Rock Anticipated: Wackestone and grainstone; minor foram-nanno ooze and chalk Site: GAB-13B Priority: 2 Position: 34ø45.4940'S, 127ø35.4358'E Water Depth: 4465 m Sediment Thickness: >3.5 km Approved Maximum Penetration: 800 m Seismic Coverage: Intersection of AGSO Lines 169/08 (SP 3987.5) and 169/09 (SP 3457.5) Objectives: The objectives of GAB-13B are to 1.Recover pelagic ooze from the middle continental rise to construct a Cenozoic and Late Cretaceous paleoceanographic record of the opening of the Southern Ocean and development of the Circum-Antarctic Current. 2.Determine the history of Cenozoic and Late Cretaceous CCD fluctuations and deep-water mass variations during the evolution of the Southern Ocean (in conjunction with Sites GAB-01C and GAB-02B). 3. Determine depositional and diagenetic facies on the middle continental rise. Drilling Program: Triple APC, XCB, RCB Logging and Downhole Operations: Triple combo, FMS/Sonic, GHMT, WST Nature of Rock Anticipated: Nanno-foram ooze and chalk (610 m), calcareous mudstone (375 m) SCIENTIFIC PARTICIPANTS* (Updated 20 August 1998) Co-Chief David A. Feary Australian Geological Survey Organisation GPO Box 378 Canbera, ACT 2601 Australia Internet: dfeary@agso.gov.au Work: (61) 2-6285-2402 Fax: (61) 2-6285-2586 Co-Chief Albert C. Hine Department of Marine Science University of South Florida, St. Petersburg 140 7th Avenue South St. Petersburg, FL 33701 U.S.A. Internet: hine@seas.marine.usf.edu Work: (813) 553-1161 Fax: (813) 553-1189 Staff Scientist/Inorganic Geochemist Mitchell J. Malone Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845 U.S.A. Internet: mitchell_malone@odp.tamu.edu Work: (409) 845-5218 Fax: (409) 845-0876 Inorganic Geochemist Peter K. Swart Rosenstiel School of Marine and Atmospheric Science University of Miami 4600 Rickenbacker Causeway Miami, FL 33149 U.S.A. Internet: pswart@rsmas.miami.edu Work: (305) 361-4103 Fax: (305) 361-4632 Inorganic Geochemist Ulrich G. Wortmann Department of Geology Eidgenossische Technische Hochschule - Zentrum Sonneggstrasse 5 Zurich 8092 Switzerland Internet: uli@bonk.ethz.ch Work: (41) 632-3694 Fax: (41) 632-1080 Organic Geochemist Richard M. Mitterer Programs in Geosciences University of Texas at Dallas P.O. Box 830688 Richardson, TX 75083-0688 U.S.A. Internet: mitterer@utdallas.edu Work: (972) 883-2462 Fax: (972) 883-2537 Paleomagnetist Roberto S. Molina Garza Department of Earth & Planetary Sciences University of New Mexico Northrop Hall Albuquerque, NM 87131-1116 U.S.A. Internet: molina@unm.edu Work: (505) 277-5261 Fax: (505) 277-8843 Paleomagnetist Michael Fuller HIGP-SOEST University of Hawaii 2525 Correa Rd. Honolulu, Hawaii 96822 USA Internet: mfuller@soest.hawaii.edu Work (808) 956-4038 Fax (808) 956-3188 Paleontologist (Planktonic Foraminifers) Charlotte A. Brunner Center for Marine Science University of Southern Mississippi Bldg. 1103, Rm. 102 Stennis Space Center, MS 39529 U.S.A. Internet: cbrunner@sunfish.st.usm.edu Work: (228) 688-3402 Fax: (228) 688-1121 Paleontologist (Planktonic Foraminifers) Qianyu Li Department of Geology and Geophysics University of Adelaide Adelaide, South Australia 5005 Australia Internet: qli@geology.adelaide.edu.au Work: (61) 8-8303-5826 Fax: (61) 8-8303-4347 Paleontologist (Benthic Foraminifers) Ann E. Holbourn Department of Paleontology Natural History Museum Cromwell Road London SW7 5BD United Kingdom Internet: a.holbourn@nhm.ac.uk Work: (44) 171-938-9046 Fax: (44) 171-938-9277 Paleontologist (Nannofossil) Bryan C. Ladner Temporary Address (Summer) One Shell Square P.O. Box 61933 New Orleans, LA 70161-1933, U.S.A. Internet: bl831855@msxsepc.shell.com Work: (504)728-7474 Permanent Address Department of Geology Florida State University Tallahasse, FL 32306-4100, USA Internet: ladner@quartz.gly.fsu.edu Work: (805) 644-5860 Fax: (805) 644-4214 Paleontologist (Nannofossil) Samir Shafik Marine Geoscience and Petroleum Geology Program Australian Geological Survey Organisation GPO Box 378 Canberra, ACT 2601 Australia Internet: sshafik@agso.gov.au Work: (61) 6-249-9436 Fax: (61) 6-249-9981 JOIDES Logging Scientist/Physical Properties Specialist Alexandra R. Isern Department of Geology and Geophysics University of Sydney Building F05 Sydney, NSW 2006 Australia Internet: aisern@es.su.oz.au Work: (61) 2-9351-3998 Fax: (61) 2-9351-0184 Stratigraphic Correlator/Physical Properties Specialist David J. Mallinson Department of Marine Science University of South Florida, St. Petersburg 140 Seventh Ave. S. St. Petersburg, FL 33701 U.S.A. Internet: davem@seas.marine.usf.edu Work: (813) 553-3927 Fax: (813) 553-1189 Physical Properties Specialist Peter L. Smart Department of Geography University of Bristol University Road Bristol BS8 1SS United Kingdom Internet: smartpl@gma.bris.ac.uk Work: (44) 1179-288305 Fax: (44) 1179-287878 Physical Properties Specialist Joellen Russell Scripps Institution of Oceanography University of California, San Diego Marine Physical Laboratory 9500 Gilman Dr. La Jolla, CA 92093-0208 USA Internet: jlrussel@ucsd.edu Work: (619) 456-2582 Fax: (619) 456-9079 Physical Properties Specialist Cecile Robin Department de Geologie Sedimentaire Universite Pierre et Marie Curie (Paris 6) Case postale 116 Aile 14-15-E4 - 4 Place Jussie 75252 Paris Cedex 05 France Internet: robin@ccr.jussieu.fr Work: (33) 1-4427-2760 Fax: (33) 1-4427-4965 Sedimentologist Ms. Miriam Andres Geologisches Institut Eidgenossische Technische Hochschule - Zentrum Sonneggstrasse-5 Zurich 8092 Switzerland Internet: miriam@erdw.ethz.ch Work: (41) 1-632-4818 Fax: (41) 1-632-1080 Sedimentologist Christian Betzler Geologisch-Palaontologisches Institut Johann Wolfgang Goethe-Universitat Frankfurt am Main Senskenberganlage 32-34 Postfach 11-19-32 Frankfurt-am-Main 60054 Federal Republic of Germany Internet: betzler@em.uni-frankfurt.d400.de Work: (49) 69-798-23107 Fax: (49) 69-798-22958 Sedimentologist Gregg R. Brooks Department of Marine Science Eckerd College 4200 54th Ave. S. St. Petersburg, FL 33711 U.S.A. Internet: brooksgr@eckerd.edu Work: (813) 864-8992 Fax: (813) 864-7964 Sedimentologist Noel P. James Department of Geological Sciences Queen's University at Kingston Kingston, Ontario K7L 3N6 Canada Internet: james@geol.queensu.ca Work: (613) 545-2597 Fax: (613) 545-6592 Sedimentologist Hideaki Machiyama Oceanic Crust Dynamics Research Japan Marine Science and Technology Center 2-15 Natsushimacho Yokosuka, Kanagawa 237 Japan Internet: bucci@jamstec.go.jp Work: (81) 468-67-3395 Fax: (81) 468-67-3409 Sedimentologist Hiroki Matsuda Department of Earth Sciences Kumamoto University 2-39-1 Kurokami Kumamoto, Kumamoto 860 Japan Internet: hmat@sci.kumamoto-u.ac.jp Work: (81) 96-342-3424 Fax: (81) 96-342-3411 Sedimentologist Juan Antonio Simo Department of Geology and Geophysics University of Wisconsin-Madison 1215 W. Dayton St. Madison, WI 53706 U. S. A. Internet: simo@geology.wisc.edu Work: (608) 262-5987 Fax: (608) 262-0693 Sedimentologist Finn Surlyk Geologisk Institut Kobenhavns Universitet Oster Voldgade 10 Kobenhavn K 1350 Denmark Internet: finns@geo.geol.ku.dk Work: (45) 3532-2453 Fax: (45) 3314-8322 LDEO Logging Scientist Mads Huuse Department of Earth Sciences University of Aarhus Finlandsgade 8, 8200 Aarhus N Denmark Internet: mhuuse@geoserver1.aau.dk Work: 45-8942-4343 Fax: 45-8610-1003 LDEO Logging Trainee Guy Spence Department of Geology University of Leicester Borehole Research Leicester LE1 7RH United Kingdom Internet: ghs2@leicester.ac.uk Work: Fax: (44) 116-252-3918 Schlumberger Engineer Robert Laronga Schlumberger Offshore Services 369 Tristar Drive Webster, TX 77598 U.S.A. Work: (281) 480-2000 Fax: (281) 480-9550 Operations Manager Eugene Pollard Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: eugene_pollard@odp.tamu.edu Work: (409) 845-2161 Fax: (409) 845-2308 Laboratory Officer Gus Gustafson Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: ted_gustafson@odp.tamu.edu Work: (409) 845-8482 Fax: (409) 845-0876 Marine Lab Specialist: Yeoperson Michiko Hitchcox Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: michiko_hitchcox@odp.tamu.edu Work: (409) 845-2483 Fax: (409) 845-0876 Marine Lab Specialist: Chemistry Dennis Graham Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: dennis_graham@odp.tamu.edu Work: (409) 845-8482 Fax: (409) 845-0876 Marine Lab Specialist: Chemistry Chieh Peng Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: chieh_peng@odp.tamu.edu Work: (409) 845-2480 Fax: (409) 845-0876 Marine Lab Specialist: Curator Lorraine Southey Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: lorraine_southey@odp.tamu.edu Work: (409) 845-8482 Fax: (409) 845-1303 Marine Lab Specialist: Assistant Curator Philip Rumford Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: phil_rumford@odp.tamu.edu Work: (409) 845-5135 Fax: (409) 845-0876 Marine Lab Specialist: Photographer Tim Fulton Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A Internet: tim_fulton@odp.tamu.edu Work: (409) 845-1183 Fax: (409) 845-4857 Marine Lab Specialist: Physical Properties Anastasia Ledwon Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: anastasia_ledwon@odp.tamu.edu Work: (409) 845-9186 Fax: (409) 845-0876 Marine Lab Specialist: Underway Geophysics Don Sims Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: don_sims@odp.tamu.edu Work: (409) 845-2481 Fax: (409) 845-0876 Marine Lab Specialist: X-Ray Robert Olivas Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: bob_olivas@odp.tamu.edu Work: (409) 845-2481 Fax: (409) 845-0876 Marine Lab Specialist: Marine Logistics Coordinator John Dyke Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: john_dyke@odp.tamu.edu Work: (409) 845-2424 Fax: (409) 845-2380 Marine Lab Specialist: Paleomagnetism TBN Marine Lab Specialist: Downhole Tools/Thin Section TBN Marine Electronics Specialist Randy W. Gjesvold Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station , TX 77845-9547 U.S.A. Internet: randy_gjesvold@odp.tamu.edu Marine Electronics Specialist Larry St. John Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: larry_st.john@odp.tamu.edu Work: (409) 845-2454 Fax: (409) 845-2308 Marine Computer Specialist Margaret Hastedt Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: margaret_hastedt@odp.tamu.edu Work: (409) 845-2480 Fax: (409) 845-4857 Marine Computer Specialist Chris Stephens Ocean Drilling Program Texas A&M University 1000 Discovery Drive College Station, TX 77845-9547 U.S.A. Internet: chris_stephens@odp.tamu.edu Work: (409) 862-4849 Fax: (409) 845-4857 Marine Lab Specialist: Student Bruce C. Horan 2 Petticoat Lane Darien, CT 06820 U.S.A. Internet: 103115.1570@compuserve.com Fax: (203) 655-2778 Marine Lab Specialist: Student Nana Quistgaard Geologisk Institut Kobenhavns Universitet Oster Volgade 10 Kobenhavn K 1350 Denmark Internet: qn270970@geo.geol.ku.dk Work: (45) 20-65-32-50 *Subject to change