The 53rd annual meeting of the Association of Earth Science Editors will take place in Regina, Saskatchewan, Canada, September 4 to 7, 2019. AESE meetings are a wonderful way to learn about earth science editing, publishing and communication. Our meetings, generally small in size, consist of two days of technical sessions and a one-day field trip, and provide an unparalleled opportunity to network with other editors, publishers, educators and others working in the earth sciences.
venter [paleont] . (a) The outer and convex part of the shell of a curved or coiled cephalopod or gastropod, or the peripheral wall of a cephalopod whorl comprising the part of the shell radially farthest from the protoconch; the underside of a nautiloid and of its conch, distinguished generally by the hyponomic sinus and often by a conchal furrow (TIP, 1964, pt. K, p.59). (b) The median region of the shell of a productid brachiopod, situated between the valve surfaces on either side of the median sector of the shell (TIP, 1965, pt. H, p.155). (c) The belly region or the lower part of the carapace of an ostracode. Cf: dorsum [paleont].
marcasite [mineral] . A common metallic light yellow or grayish orthorhombic mineral: FeS2. It is dimorphous with pyrite and resembles it in appearance, but marcasite has a lower specific gravity, less chemical stability, and usually a paler color. Marcasite often occurs in sedimentary rocks (such as chalk) in the form of nodules or concretions with a radiating fibrous structure. Syn: white iron pyrites; iron pyrites; white pyrite; white pyrites; cockscomb pyrites; spear pyrites; lamellar pyrites.