Table T1. Defining characteristics for the petrophysical units of Site 1098.

Table T1. Defining characteristics for the petrophysical units of Site 1098.

Petrophysical unit

Depth (mbsf)

Defining characteristics/lithology

Notes

A 0-~9 Muddy diatom ooze alternating every ~0.5 m between M_D and L_D. The unit consists uniquely of petrophysical Group 2. The alternating lithologic layers can be clearly seen in the pattern of the MGS data.

B 9-24 Mostly L_D layered with M_D. There is a noticeable decrease (an order of magnitude) and smoothing of the MGS data compared with Unit A. Consists of petrophysical Group 1.

C 24-28 Drop in variability of physical properties data compared with higher sediments. MGS and porosity data increase and decrease, respectively, with depth. The unit consists of petrophysical Groups 1 and 3 and is dominated by a turbidite between 23 and 27 mbsf, following which there is a short drop in MGS and a rise in porosity. The depth range discrepancy between the turbidite and Unit C is clarified below.

D 28-38 Defined by its heterogeneous physical properties. The MGS varies greatly, and there is a high amount of scatter in the porosity data. There are four lithologies within this unit: M_D, L_D, T_D, and T_T. The unit consists predominantly of petrophysical Group 2, with small isolated regions of Groups 1, 3, and 4.

E 38-43 Four lithologies: M_D, L_D, T_D, and S. There is a noticeable change in physical properties characteristics associated with this unit, mostly because the unit is banded on either side by higher MGS values. There is a gradual decrease, then increase, in the MGS and GRA data with depth in this unit; the porosity curve shows the inverse. Contains petrophysical Groups 1, 2, and 3. It is proposed that the gradual decrease, then increase, in the MGS and GRA data with depth in this unit and the inverse porosity curve are a result of changes in grain size and sorting.

F 43-45 Corresponds with lithology D and the base of lithologic Unit IB. Defined by petrophysical Group 4. Properties reflect poor sorting and possibly subglacial overconsolidation.

Petrophysical unit	Depth (mbsf)	Defining characteristics/lithology	Notes
A	0-~9	Muddy diatom ooze alternating every ~0.5 m between M_D and L_D. The unit consists uniquely of petrophysical Group 2.	The alternating lithologic layers can be clearly seen in the pattern of the MGS data.
B	9-24	Mostly L_D layered with M_D. There is a noticeable decrease (an order of magnitude) and smoothing of the MGS data compared with Unit A. Consists of petrophysical Group 1.
C	24-28	Drop in variability of physical properties data compared with higher sediments. MGS and porosity data increase and decrease, respectively, with depth. The unit consists of petrophysical Groups 1 and 3 and is dominated by a turbidite between 23 and 27 mbsf, following which there is a short drop in MGS and a rise in porosity.	The depth range discrepancy between the turbidite and Unit C is clarified below.
D	28-38	Defined by its heterogeneous physical properties. The MGS varies greatly, and there is a high amount of scatter in the porosity data. There are four lithologies within this unit: M_D, L_D, T_D, and T_T. The unit consists predominantly of petrophysical Group 2, with small isolated regions of Groups 1, 3, and 4.
E	38-43	Four lithologies: M_D, L_D, T_D, and S. There is a noticeable change in physical properties characteristics associated with this unit, mostly because the unit is banded on either side by higher MGS values. There is a gradual decrease, then increase, in the MGS and GRA data with depth in this unit; the porosity curve shows the inverse. Contains petrophysical Groups 1, 2, and 3.	It is proposed that the gradual decrease, then increase, in the MGS and GRA data with depth in this unit and the inverse porosity curve are a result of changes in grain size and sorting.
F	43-45	Corresponds with lithology D and the base of lithologic Unit IB. Defined by petrophysical Group 4.	Properties reflect poor sorting and possibly subglacial overconsolidation.

Note: M_D = massive bioturbated beds, L_D = laminated beds, T_D = muddy/clayey diatom ooze turbidite, T_T = terrigenous turbidite, S = slump laminated in sediment, D = diamict.